Publications

Abstract

Perceptual and sensorimotor timing skills can be thoroughly assessed with the Battery for the Assessment of Auditory Sensorimotor and Timing Abilities (BAASTA). The battery has been used for testing rhythmic skills in healthy adults and patient populations (e.g., with Parkinson disease), showing sensitivity to timing and rhythm deficits. Here we assessed the test-retest reliability of the BAASTA in 20 healthy adults. Participants were tested twice with the BAASTA, implemented on a tablet interface, with a 2-week interval. They completed 4 perceptual tasks, namely, duration discrimination, anisochrony detection with tones and music, and the Beat Alignment Test (BAT). Moreover, they completed motor tasks via finger tapping, including unpaced and paced tapping with tones and music, synchronization-continuation, and adaptive tapping to a sequence with a tempo change. Despite high variability among individuals, the results showed good test-retest reliability in most tasks. A slight but significant improvement from test to retest was found in tapping with music, which may reflect a learning effect. In general, the BAASTA was found a reliable tool for evaluating timing and rhythm skills.

Abstract

An event-related brain potential experiment was carried out to investigate the influence of semantic and syntactic context constraints on lexical selection and integration in spoken-word comprehension. Subjects were presented with constraining spoken sentences that contained a critical word that was either (a) congruent, (b) semantically and syntactically incongruent, but beginning with the same initial phonemes as the congruent critical word, or (c) semantically and syntactically incongruent, beginning with phonemes that differed from the congruent critical word. Relative to the congruent condition, an N200 effect reflecting difficulty in the lexical selection process was obtained in the semantically and syntactically incongruent condition where word onset differed from that of the congruent critical word. Both incongruent conditions elicited a large N400 followed by a left anterior negativity (LAN) time-locked to the moment of word category violation and a P600 effect. These results would best fit within a cascaded model of spoken-word processing, proclaiming an optimal use of contextual information during spokenword identification by allowing for semantic and syntactic processing to take place in parallel after bottom-up activation of a set of candidates, and lexical integration to proceed with a limited number of candidates that still match the acoustic input.

Abstract

Speech prosody, the variation in sentence melody and rhythm, plays a crucial role in sentence comprehension. Specifically, changes in intonational pitch along a sentence can affect our understanding of who did what to whom. To date, it remains unclear how the brain processes this particular use of intonation and which brain regions are involved. In particular, one central matter of debate concerns the lateralisation of intonation processing. To study the role of intonation in sentence comprehension, we designed a functional MRI experiment in which participants listened to spoken sentences. Critically, the interpretation of these sentences depended on either intonational or grammatical cues. Our results
showed stronger functional activity in the left inferior frontal gyrus (IFG) when the intonational cue was crucial for sentence comprehension compared to when it was not. When instead a grammatical cue was crucial for sentence comprehension, we found involvement of an overlapping region in the left IFG, as well as in a posterior temporal
region. A further analysis revealed that the lateralisation of intonation processing depends on its role in syntactic processing: activity in the IFG was lateralised to the left hemisphere when intonation was the only source of information to comprehend the sentence. In contrast, activity in the IFG was right-lateralised when intonation did not contribute to sentence comprehension. Together, these results emphasise the key role of the left IFG in sentence comprehension, showing the importance of this region when intonation
establishes sentence structure. Furthermore, our results provide evidence for the theory
that the lateralisation of prosodic processing is modulated by its linguistic role.

Abstract

In synaesthetes specific sensory stimuli (e.g., black letters) elicit additional experiences (e.g. colour). Synaesthesia is highly prevalent among individuals with autism spectrum disorder but the mechanisms of this co-occurrence are not clear. We hypothesized autism and synaesthesia share atypical sensory sensitivity and perception. We assessed autistic traits, sensory sensitivity, and visual perception in two synaesthete populations. In Study 1, synaesthetes (N=79, of different types) scored higher than non-synaesthetes (N=76) on the Attention-to-detail and Social skills subscales of the Autism Spectrum Quotient indexing autistic traits, and on the Glasgow Sensory Questionnaire indexing sensory hypersensitivity and hyposensitivity which frequently occur in autism. Synaesthetes performed two local/global visual tasks because individuals with autism typically show a bias toward detail processing. In synaesthetes, elevated motion coherence thresholds suggested reduced global motion perception and higher accuracy on an embedded figures task suggested enhanced local perception. In Study 2 sequence-space synaesthetes (N=18) completed the same tasks. Questionnaire and embedded figures results qualitatively resembled Study 1 results but no significant group differences with non-synaesthetes (N=20) were obtained. Unexpectedly, sequence-space synaesthetes had reduced motion coherence thresholds. Altogether, our studies suggest atypical sensory sensitivity and a bias towards detail processing are shared features of synaesthesia and autism spectrum disorder.

Abstract

In normal conversation, speakers translate thoughts into words at high speed. To enable this speed, the retrieval of distinct types of linguistic knowledge has to be orchestrated with millisecond precision. The nature of this orchestration is still largely unknown. This report presents dynamic measures of the real-time activation of two basic types of linguistic knowledge, syntax and phonology. Electrophysiological data demonstrate that during noun-phrase production speakers retrieve the syntactic gender of a noun before its abstract phonological properties. This two-step process operates at high speed: the data show that phonological information is already available 40 milliseconds after syntactic properties have been retrieved.

Abstract

Social learning in chimpanzees has been studied extensively and it is now widely accepted that chimpanzees have the capacity to learn from conspecifics through a multitude of mechanisms. Very few studies, however, have documented the existence of spontaneously emerged 'traditions' in chimpanzee communities. While the rigor of experimental studies is helpful to investigate social learning mechanisms, documentation of naturally occurring traditions is necessary to understand the relevance of social learning in the real lives of animals. In this study, we report on chimpanzees spontaneously copying a seemingly non-adaptive behaviour ("grass-in- ear behaviour"). The behaviour entailed chimpanzees selecting a stiff, straw-like blade of grass, inserting the grass into one of their own ears, adjusting the position, and then leaving it in their ear during subsequent activities. Using a daily focal follow procedure, over the course of one year, we observed 8 (out of 12) group members engaging in this peculiar behaviour. Importantly, in the 3 neighbouring groups of chimpanzees (n=82), this behaviour was only observed once, indicating that ecological factors were not determiners of the prevalence of this behaviour. These observations show that chimpanzees have a tendency to copy each other's behaviour, even when the adaptive value of the behaviour is presumably absent.

Abstract

In simultaneous interpreting, speech comprehension and production processes have to be coordinated in close temporal proximity. To examine the coordination, Dutch-English bilingual participants were presented with narrative fragments recorded in English at speech rates varying from 100 to 200 words per minute and they were asked to translate the fragments into Dutch (interpreting) or repeat them in English (shadowing). Interpreting yielded more errors than shadowing at every speech rate, and increasing speech rate had a stronger negative effect on interpreting than on shadowing. To understand the differential effect of speech rate, a computational model was created of sub-lexical and lexical processes in comprehension and production. Computer simulations revealed that the empirical findings could be captured by assuming a bottleneck preventing simultaneous lexical selection in production and comprehension. To conclude, our empirical and modelling results suggest the existence of a lexical bottleneck that limits the translation of narratives at high speed.

Abstract

In this review, we explore the extent to which the recent evidence for conformity in nonhuman animals may alternatively be explained by the animals' preference for social information regardless of the number of individuals demonstrating the respective behaviour. Conformity as a research topic originated in human psychology and has been described as the phenomenon in which individuals change their behaviour to match the behaviour displayed by the majority of group members. Recent studies have aimed to investigate the same process in nonhuman animals; however, most of the adopted designs have not been able to control for social influences independent of any majority influence and some studies have not even incorporated a majority in their designs. This begs the question to what extent the ‘conformity interpretation’ is preliminary and should be revisited in light of animals' general susceptibility to social influences. Similarly, demarcating social from majority influences sheds new light on the original findings in human psychology and motivates reinterpretation of the reported behavioural patterns in terms of social instead of majority influences. Conformity can have profound ramifications for individual fitness and group dynamics; identifying the exact source responsible for animals' behavioural adjustments is essential for understanding animals' learning biases and interpreting cross-species data in terms of evolutionary processes.

Abstract

Learning new vocabulary from context typically requires multiple encounters during which word meaning can be retrieved from memory or inferred from context. We compared the effect of memory retrieval and context inferences on short‐ and long‐term retention in three experiments. Participants studied novel words and then practiced the words either in an uninformative context that required the retrieval of word meaning from memory (“I need the funguo”) or in an informative context from which word meaning could be inferred (“I want to unlock the door: I need the funguo”). The informative context facilitated word comprehension during practice. However, later recall of word form and meaning and word recognition in a new context were better after successful retrieval practice and retrieval practice with feedback than after context‐inference practice. These findings suggest benefits of retrieval during contextualized vocabulary learning whereby the uninformative context enhanced word retention by triggering memory retrieval.

Abstract

Speech perception is shaped by listeners' prior experience with speakers. Listeners retune their phonetic category boundaries after encountering ambiguous sounds in order to deal with variations between speakers. Repeated exposure to an unambiguous sound, on the other hand, leads to a decrease in sensitivity to the features of that particular sound. This study investigated whether these changes in the listeners' perceptual systems can generalise to the perception of speech from a novel speaker. Specifically, the experiments looked at whether visual information about the identity of the speaker could prevent generalisation from occurring. In Experiment 1, listeners retuned auditory category boundaries using audiovisual speech input. This shift in the category boundaries affected perception of speech from both the exposure speaker and a novel speaker. In Experiment 2, listeners were repeatedly exposed to unambiguous speech either auditorily or audiovisually, leading to a decrease in sensitivity to the features of the exposure sound. Here, too, the changes affected the perception of both the exposure speaker and the novel speaker. Together, these results indicate that changes in the perceptual system can affect the perception of speech from a novel speaker and that visual speaker identity information did not prevent this generalisation.

Abstract

The VALID Data Archive is an open multimedia data archive in which data from children and adults with language and/or communication problems are brought together. A pilot project, funded by CLARIN-NL, was carried out in which five existing data sets were curated. This pilot enabled us to build up experience in conserving different kinds of pathological language data in a searchable and persistent manner. These data sets reflect current research in language pathology rather well, both in the range of designs and the variety in pathological problems, such as Specific Language Impairment, deafness, dyslexia, and ADHD. In this paper, we present the VALID initiative, explain the curation process and discuss the materials of the data sets.

Abstract

An essential phenomenon in the development towards syntactic maturity after early childhood is the increasing use of so-called sentence-combining transformations. Especially by using subordination, complex sentences are produced. The research reported here is an attempt to arrive at a more adequate characterization and explanation. Our starting point was an analysis of 280 texts written by Dutch-speaking pupils of the two highest grades of the primary school and the four lowest grades of three different types of secondary education. It was examined whether systematic shifts in the use of certain groups of so-called function words could be traced. We concluded that the development of the syntactic formulating ability can be characterized as an increase in connectivity: the use of all kinds of function words which explicitly mark logico-semantic relations between propositions. This development starts by inserting special adverbs and coordinating conjunctions resulting in various types of coordination. In a later stage, the syntactic patterning of the sentence is affected as well (various types of subordination). The increase in sentence complexity is only one aspect of the entire development. An explanation for the increase in connectivity is offered based upon a distinction between narrative and expository language use. The latter, but not the former, is characterized by frequent occurrence of connectives. The development in syntactic formulating ability includes a high level of skill in expository language use. Speed of development is determined by intensity of training, e.g. in scholastic and occupational settings.

Abstract

We report on a prospective longitudinal research programme exploring the connection between language acquisition deficits and dyslexia. The language development profile of children at-risk for dyslexia is compared to that of age-matched controls as well as of children who have been diagnosed with specific language impairment (SLI). The experiments described concern the perception and production of grammatical morphology, categorical perception of speech sounds, phonological processing (non-word repetition), mispronunciation detection, and rhyme detection. The results of each of these indicate that the at-risk children as a group underperform in comparison to the controls, and that, in most cases, they approach the SLI group. It can be concluded that dyslexia most likely has precursors in language development, also in domains other than those traditionally considered conditional for the acquisition of literacy skills. The dyslexia-SLI connection awaits further, particularly qualitative, analyses.

Abstract

In a highly social species like chimpanzees, the process by which individuals become attuned to their social environment may be of vital importance to their chances of survival. Typically, this socializing process, defined by all acquisition experiences and fine-tuning efforts of social interaction patterns during ontogeny, occurs in large part through parental investment. In this study, we investigated whether maternal presence would enhance the socializing process in chimpanzees by comparing the social interactions of orphaned and mother-reared individuals at the Chimfunshi Wildlife Orphanage Trust in Zambia. As response variables, we selected social interactions during which an elaborate level of fine-tuning is assumed to be necessary for sustaining the interaction and preventing escalation: social play. Comparing orphaned (n=8) to sex- and age-matched mother-reared juvenile chimpanzees (n=9), we hypothesized that the orphaned juveniles would play less frequently than the mother-reared and would be less equipped for fine-tuning social play (which we assayed by rates of aggression) because of the lack of a safe and facilitating social environment provided by the mother. First, contrary to our hypothesis, results showed that the orphaned juveniles engaged in social play more frequently than the mother-reared juveniles, although for significantly shorter amounts of time. Second, in support of our hypothesis, results showed that social play of the orphaned juveniles more often resulted in aggression than social play of the mother-reared juveniles. In conjunction, these results may indicate that, just like in humans, chimpanzee mothers provide their offspring with adequate social skills that might be of pivotal importance for future challenges like successful group-living and securing competitive fitness advantages.

Abstract

This study explores the effect of feedback with hints on students’ recall of words. In three classroom experiments, high school students individually practiced vocabulary words through computerized retrieval practice with either standard show-answer feedback (display of answer) or hints feedback after incorrect responses. Hints feedback gave students a second chance to find the correct response using orthographic (Experiment 1), mnemonic (Experiment 2), or cross-language hints (Experiment 3). During practice, hints led to a shift of practice time from further repetitions to longer feedback processing but did not reduce (repeated) errors. There was no effect of feedback on later recall except when the hints from practice were also available on the test, indicating limited transfer of practice with hints to later recall without hints (in Experiments 1 and 2). Overall, hints feedback was not preferable over show-answer feedback. The common notion that hints are beneficial may not hold when the total practice time is limited.

Abstract

This study investigated how great apes and human infants use imperative pointing to request objects. In a series of three experiments (infants, N = 44; apes, N = 12), subjects were given the opportunity to either point to a desired object from a distance or else to approach closer and request it proximally. The apes always approached close to the object, signaling their request through instrumental actions. In contrast, the infants quite often stayed at a distance, directing the experimenters' attention to the desired object through index-finger pointing, even when the object was in the open and they could obtain it by themselves. Findings distinguish 12-month-olds' imperative pointing from ontogenetic and phylogenetic earlier forms of ritualized reaching.

Abstract

Ample evidence shows that the basal ganglia play an important role in cognitive flexibility. However, traditionally, cognitive processes have most commonly been associated with the prefrontal cortex. Indeed, current theoretical models of basal ganglia function suggest the basal ganglia interact with the prefrontal cortex and thalamus, via anatomical fronto-striato-thalamic circuits, to implement cognitive flexibility. Here we aimed to assess this hypothesis in humans by associating individual differences in cognitive flexibility with white matter microstructure of the basal ganglia. To this end we employed an attention switching paradigm in adults with ADHD and controls, leading to a broad range in task performance. Attention switching performance could be predicted based on individual differences in white matter microstructure in/around the basal ganglia. Crucially, local white matter showing this association projected to regions in the prefrontal cortex and thalamus. Our findings highlight the crucial role of the basal ganglia and the fronto-striato-thalamic circuit for cognitive flexibility.

Abstract

Three experiments investigated the voicing distinction in Dutch initial labial and alveolar plosives. The difference between voiced and voiceless Dutch plosives is generally described in terms of the presence or absence of prevoicing (negative voice onset time). Experiment 1 showed, however, that prevoicing was absent in 25% of voiced plosive productions across 10 speakers. The production of prevoicing was influenced by place of articulation of the plosive, by whether the plosive occurred in a consonant cluster or not, and by speaker sex. Experiment 2 was a detailed acoustic analysis of the voicing distinction, which identified several acoustic correlates of voicing. Prevoicing appeared to be by far the best predictor. Perceptual classification data revealed that prevoicing was indeed the strongest cue that listeners use when classifying plosives as voiced or voiceless. In the cases where prevoicing was absent, other acoustic cues influenced classification, such that some of these tokens were still perceived as being voiced. These secondary cues were different for the two places of articulation. We discuss the paradox raised by these findings: although prevoicing is the most reliable cue to the voicing distinction for listeners, it is not reliably produced by speakers.

Abstract

How do children use phonological knowledge about spoken language in acquiring literacy? Phonological precursors of literacy include phonological awareness, speech decoding skill, and lexical specificity (i.e., the richness of phonological representations in the mental lexicon). An intervention study investigated whether early literacy skills can be enhanced by training lexical specificity. Forty-two prereading 4-year-olds were randomly assigned to either an experimental group that was taught pairs of new words that differed minimally or a control group that received numeracy training. The experimental group gained on a rhyme awareness task, suggesting that learning phonologically specific new words fosters phonological awareness.

Abstract

Heterozygous mutations of the Forkhead-box protein 2 (FOXP2) gene in humans cause childhood apraxia of speech. Loss of Foxp2 in mice is known to affect striatal development and impair motor skills. However, it is unknown if striatal excitatory/inhibitory balance is affected during development and if the imbalance persists into adulthood. We investigated the effect of reduced Foxp2 expression, via a loss-of-function mutation, on striatal medium spiny neurons (MSNs). Our data show that heterozygous loss of Foxp2 decreases excitatory (AMPA receptor-mediated) and increases inhibitory (GABA receptor-mediated) currents in D1 dopamine receptor positive MSNs of juvenile and adult mice. Furthermore, reduced Foxp2 expression increases GAD67 expression, leading to both increased presynaptic content and release of GABA. Finally, pharmacological blockade of inhibitory activity in vivo partially rescues motor skill learning deficits in heterozygous Foxp2 mice. Our results suggest a novel role for Foxp2 in the regulation of striatal direct pathway activity through managing inhibitory drive.

Abstract

Human societies are characterized by more cultural diversity than chimpanzee communities. However, it is currently unclear what mechanism might be driving this difference. Because reliance on social information is a pivotal characteristic of culture, we investigated individual and social information reliance in children and chimpanzees. We repeatedly presented subjects with a reward-retrieval task on which they had collected conflicting individual and social information of equal accuracy in counterbalanced order. While both species relied mostly on their individual information, children but not chimpanzees searched for the reward at the socially demonstrated location more than at a random location. Moreover, only children used social information adaptively when individual knowledge on the location of the reward had not yet been obtained. Social information usage determines information transmission and in conjunction with mechanisms that create cultural variants, such as innovation, it facilitates diversity. Our results may help explain why humans are more culturally diversified than chimpanzees

Abstract

When formulating simple sentences to describe pictured events, speakers look at the referents they are describing in the order of mention. Accounts of incrementality in sentence production rely heavily on analyses of this gaze-speech link. To identify systematic sources of variability in message and sentence formulation, two experiments evaluated differences in formulation for sentences describing “easy” and “hard” events (more codable and less codable events) with preferred and dispreferred structures (actives and passives). Experiment 1 employed a subliminal cuing manipulation and a cumulative priming manipulation to increase production of passive sentences. Experiment 2 examined the influence of event codability on formulation without a cuing manipulation. In both experiments, speakers showed an early preference for looking at the agent of the event when constructing active sentences. This preference was attenuated by event codability, suggesting that speakers were less likely to prioritize encoding of a single character at the outset of formulation in “easy” events than in “harder” events. Accessibility of the agent influenced formulation primarily when an event was “harder” to describe. Formulation of passive sentences in Experiment 1 also began with early fixations to the agent but changed with exposure to passive syntax: speakers were more likely to consider the patient as a suitable sentential starting point after cumulative priming. The results show that the message-to-language mapping in production can vary with the ease of encoding an event structure and of generating a suitable linguistic structure.

Abstract

Watching a speaker say words benefits subsequent auditory recognition of the same words. In this study, we tested whether hearing words also facilitates subsequent phonological processing from visual speech, and if so, whether speaker repetition influences the magnitude of this word repetition priming. We used long-term cross-modal repetition priming as a means to investigate the underlying lexical representations involved in listening to and seeing speech. In Experiment 1, listeners identified auditory-only words during exposure and visual-only words at test. Words at test were repeated or new and produced by the exposure speaker or a novel speaker. Results showed a significant effect of cross-modal word repetition priming but this was unaffected by speaker changes. Experiment 2 added an explicit recognition task at test. Listeners’ lipreading performance was again improved by prior exposure to auditory words. Explicit recognition memory was poor, and neither word repetition nor speaker repetition improved it. This suggests that cross-modal repetition priming is neither mediated by explicit memory nor improved by speaker information. Our results suggest that phonological representations in the lexicon are shared across auditory and visual processing, and that speaker information is not transferred across modalities at the lexical level.

Abstract

Interpersonal discourse particles (DPs), such as Dutch inderdaad (≈‘indeed’) and eigenlijk (≈‘actually’) are highly frequent in everyday conversational interaction. Despite extensive theoretical descriptions of their polyfunctionality, little is known about how they are used by language comprehenders. In two visual world eye-tracking experiments involving an online dialogue completion task, we asked to what extent inderdaad, confirming an inferred expectation, and eigenlijk, contrasting with an inferred expectation, influence real-time understanding of dialogues. Answers in the dialogues contained a DP or a control adverb, and a critical discourse referent was replaced by a beep; participants chose the most likely dialogue completion by clicking on one of four referents in a display. Results show that listeners make rapid and fine-grained situation-specific inferences about the use of DPs, modulating their expectations about how the dialogue will unfold. Findings further specify and constrain theories about the conversation-managing function and polyfunctionality of DPs.

Abstract

Non-conscious visual processing of different object categories was investigated in a rare patient with bilateral destruction of the visual cortex (V1) and clinical blindness over the entire visual field. Images of biological and non-biological object categories were presented consisting of human bodies, faces, butterflies, cars, and scrambles. Behaviorally, only the body shape induced higher perceptual sensitivity, as revealed by signal detection analysis. Passive exposure to bodies and faces activated amygdala and superior temporal sulcus. In addition, bodies also activated the extrastriate body area, insula, orbitofrontal cortex (OFC) and cerebellum. The results show that following bilateral damage to the primary visual cortex and ensuing complete cortical blindness, the human visual system is able to process categorical properties of human body shapes. This residual vision may be based on V1-independent input to body-selective areas along the ventral stream, in concert with areas involved in the representation of bodily states, like insula, OFC, and cerebellum.

Abstract

In this fMRI study we investigate the neural correlates of information structure integration during sentence comprehension in Dutch. We looked into how prosodic cues (pitch accents) that signal the information status of constituents to the listener (new information) are combined with other types of information during the unification process. The difficulty of unifying the prosodic cues into overall sentence meaning was manipulated by constructing sentences in which the pitch accent did (focus-accent agreement), and sentences in which the pitch accent did not (focus-accent disagreement) match the expectations for focus constituents of the sentence. In case of a mismatch, the load on unification processes increases. Our results show two anatomically distinct effects of focus-accent disagreement, one located in the posterior left inferior frontal gyrus (LIFG, BA6/44), and one in the more anterior-ventral LIFG (BA 47/45). Our results confirm that information structure is taken into account during unification, and imply an important role for the LIFG in unification processes, in line with previous fMRI studies.

Abstract

Although much is known about how nouns facilitate object categorization, very little is known about how verbs (e.g., posture verbs such as stand or lie) facilitate object categorization. Native Dutch speakers are a unique population to investigate this issue with because the configurational categories distinguished by staan (to stand) and liggen (to lie) are inherent in everyday Dutch language. Using an ERP component (N2pc), four experiments demonstrate that selection of posture verb categories is rapid (between 220–320 ms). The effect was attenuated, though present, when removing the perceptual distinction between categories. A similar attenuated effect was obtained in native English speakers, where the category distinction is less familiar, and when category labels were implicit for native Dutch speakers. Our results are among the first to demonstrate that category search based on verbs can be rapid, although extensive linguistic experience and explicit labels may not be necessary to facilitate categorization in this case.

Abstract

In the recent literature, the effects of noninvasive neurostimulation on cognitive functioning appear to lack consistency and replicability. We propose that such effects may be concealed unless dedicated, sensitive, and process-specific dependent measures are used. The expression and subsequent suppression of response capture are often studied using conflict tasks. Response-time distribution analyses have been argued to provide specific measures of the susceptibility to make fast impulsive response errors, as well as the proficiency of the selective suppression of these impulses. These measures of response capture and response inhibition are particularly sensitive to experimental manipulations and clinical deficiencies that are typically obfuscated in commonly used overall performance analyses. Recent work using structural and functional imaging techniques links these behavioral outcome measures to the integrity of frontostriatal networks. These studies suggest that the presupplementary motor area (pre-SMA) is linked to the susceptibility to response capture whereas the right inferior frontal cortex (rIFC) is associated with the selective suppression of action impulses. Here, we used repetitive transcranial magnetic stimulation (rTMS) to test the causal involvement of these two cortical areas in response capture and inhibition in the Simon task. Disruption of rIFC function specifically impaired selective suppression of conflicting action tendencies, whereas the anticipated increase of fast impulsive errors after perturbing pre-SMA function was not confirmed. These results provide a proof of principle of the notion that the selection of appropriate dependent measures is perhaps crucial to establish the effects of neurostimulation on specific cognitive functions.

Abstract

Farine and Aplin (1) question the validity of our study reporting group-specific social dynamics in chimpanzees (2). As alternative to our approach, Farine and Aplin advance a “prenetwork permutation” methodology that tests against random assortment (3). We appreciate Farine and Aplin’s interest and applied their suggested approaches to our data. The new analyses revealed highly similar results to those of our initial approach. We further dispel Farine and Aplin’s critique by outlining its incompatibility to our study system, methodology, and analysis.First, when we apply the suggested prenetwork permutation to our proximity dataset, we again find significant population-level differences in association rates, while controlling for population size [as derived from Farine and Aplin’s script (4); original result, P < 0.0001; results including prenetwork permutation, P < 0.0001]. Furthermore, when we … ↵1To whom correspondence may be addressed. Email: ejcvanleeuwen{at}gmail.com.

Abstract

Social information use is a pivotal characteristic of the human species. Avoiding the cost of individual exploration, social learning confers substantial fitness benefits under a wide variety of environmental conditions, especially when the process is governed by biases toward relative superiority (e.g., experts, the majority). Here, we examine the development of social information use in children aged 4–14 years (n = 605) across seven societies in a standardised social learning task. We measured two key aspects of social information use: general reliance on social information and majority preference. We show that the extent to which children rely on social information depends on children’s cultural background. The extent of children’s majority preference also varies cross-culturally, but in contrast to social information use, the ontogeny of majority preference follows a U-shaped trajectory across all societies. Our results demonstrate both cultural continuity and diversity in the realm of human social learning.

Abstract

Atypical visual segmentation, affecting object perception, might contribute to face processing problems in Autism Spectrum Disorder (ASD). The current study investigated impairments in visual segmentation of faces in ASD. Thirty participants (ASD: 16; Control: 14) viewed texture-defined faces, houses, and homogeneous images, while electroencephalographic and behavioral responses were recorded. The ASD group showed slower face-segmentation related brain activity and longer segmentation reaction times than the control group, but no difference in house-segmentation related activity or behavioral performance. Furthermore, individual differences in face-segmentation but not house-segmentation correlated with score on the Autism Quotient. Segmentation is thus selectively impaired for faces in ASD, and relates to the degree of ASD traits. Face segmentation relates to recurrent connectivity from the fusiform face area (FFA) to the visual cortex. These findings thus suggest that atypical connectivity from the FFA might contribute to delayed face processing in ASD.

Abstract

The efficiency of neuronal information transfer in activated brain networks may affect behavioral performance.
Gamma-band synchronization has been proposed to be a mechanism that facilitates neuronal processing of
behaviorally relevant stimuli. In line with this, it has been shown that strong gamma-band activity in visual
cortical areas leads to faster responses to a visual go cue. We investigated whether there are directly observable
consequences of trial-by-trial fluctuations in non-invasively observed gamma-band activity on the neuronal
response. Specifically, we hypothesized that the amplitude of the visual evoked response to a go cue can be
predicted by gamma power in the visual system, in the window preceding the evoked response. Thirty-three
human subjects (22 female) performed a visual speeded response task while their magnetoencephalogram
(MEG) was recorded. The participants had to respond to a pattern reversal of a concentric moving grating. We
estimated single trial stimulus-induced visual cortical gamma power, and correlated this with the estimated single
trial amplitude of the most prominent event-related field (ERF) peak within the first 100 ms after the pattern
reversal. In parieto-occipital cortical areas, the amplitude of the ERF correlated positively with gamma power, and
correlated negatively with reaction times. No effects were observed for the alpha and beta frequency bands,
despite clear stimulus onset induced modulation at those frequencies. These results support a mechanistic model,
in which gamma-band synchronization enhances the neuronal gain to relevant visual input, thus leading to more
efficient downstream processing and to faster responses.

Abstract

In lexical development, the specificity of phonological representations is important. The ability to build phonologically specific lexical representations predicts the number of words a child knows (vocabulary breadth), but it is not clear if it also fosters how well words are known (vocabulary depth). Sixty-six children were studied in kindergarten (age 5;7) and first grade (age 6;8). The predictive value of the ability to learn phonologically similar new words, phoneme discrimination ability, and phonological awareness on vocabulary breadth and depth were assessed using hierarchical regression. Word learning explained unique variance in kindergarten and first-grade vocabulary depth, over the other phonological factors. It did not explain unique variance in vocabulary breadth. Furthermore, even after controlling for kindergarten vocabulary breadth, kindergarten word learning still explained unique variance in first-grade vocabulary depth. Skill in learning phonologically similar words appears to predict knowledge children have about what words mean.

Abstract

In sentence production, grammatical advance planning scope depends on contextual factors (e.g., time pressure), linguistic factors (e.g., ease of structural processing), and cognitive factors (e.g., production speed). The present study tests the influence of the availability of multiple syntactic alternatives (i.e., syntactic flexibility) on the scope of advance planning during the recall of Dutch dative phrases. We manipulated syntactic flexibility by using verbs with a strong bias or a weak bias toward one structural alternative in sentence frames accepting both verbs (e.g., strong/weak bias: De ober schotelt/serveert de klant de maaltijd [voor] “The waiter dishes out/serves the customer the meal”). To assess lexical planning scope, we varied the frequency of the first post-verbal noun (N1, Experiment 1) or the second post-verbal noun (N2, Experiment 2). In each experiment, 36 speakers produced the verb phrases in a rapid serial visual presentation (RSVP) paradigm. On each trial, they read a sentence presented one word at a time, performed a short distractor task, and then saw a sentence preamble (e.g., De ober…) which they had to complete to form the presented sentence. Onset latencies were compared using linear mixed effects models. N1 frequency did not produce any effects. N2 frequency only affected sentence onsets in the weak verb bias condition and especially in slow speakers. These findings highlight the dependency of planning scope during sentence recall on the grammatical properties of the verb and the frequency of post-verbal nouns. Implications for utterance planning in everyday speech are discussed.

Abstract

Meermalen is getracht om syntactische formuleenuuirdigheid direct en objectief te meten aan de hand van gesproken of geschreven teksten. Uitgangspunt hierbij vormde in de regel de syntactische complexiteit van de geproduceerde taaluitingen. Dit heeft echter niet geleid tot een plausibele, duidelijk omschreven en praktisch bruikbare index. N.a.v. een kritische bespreking van de notie complexiteit wordt in dit artikel als nieuw criterium voorgesteld de connectiviteit van de taaluitingen; de expliciete aanduiding van logiscli-scmantische relaties tussen proposities. Connectiviteit is gemakkelijk scoorbaar aan de hand van functiewoorden die verschillende vormen van nevenschikkend en onderschikkend zinsverband markeren. Deze nieuwe index ondetrangt de kritiek die op complexiteit gegeven kon worden, blijkt duidelijk te discrimineren tussen groepen leerlingen die van elkaar verschillen naar leeftijd en opleidingsniveau, en sluit aan bij recente taalpsychologische en sociolinguïstische theorie. Tot besluit worden enige onderwijskundige implicaties aangegeven.

Abstract

Reactive and proactive subtypes of aggression have been recognized to help parse etiological heterogeneity of this complex phenotype. With a heritability of about 50%, genetic factors play a role in the development of aggressive behavior. Imaging studies implicate brain structures related to social behavior in aggression etiology, most notably the amygdala and striatum. This study aimed to gain more insight into the pathways from genetic risk factors for aggression to aggression phenotypes. To this end, we conducted genome-wide gene-based cross-trait meta-analyses of aggression with the volumes of amygdala, nucleus accumbens and caudate nucleus to identify genes influencing both aggression and aggression-related brain volumes. We used data of large-scale genome-wide association studies (GWAS) of: (a) aggressive behavior in children and adolescents (EAGLE, N = 18,988); and (b) Magnetic Resonance Imaging (MRI)-based volume measures of aggression-relevant subcortical brain regions (ENIGMA2, N = 13,171). Second, the identified genes were further investigated in a sample of healthy adults (mean age (SD) = 25.28 (4.62) years; 43% male) who had genome-wide genotyping data and questionnaire data on aggression subtypes available (Brain Imaging Genetics, BIG, N = 501) to study their effect on reactive and proactive subtypes of aggression. Our meta-analysis identified two genes, MECOM and AVPR1A, significantly associated with both aggression risk and nucleus accumbens (MECOM) and amygdala (AVPR1A) brain volume. Subsequent in-depth analysis of these genes in healthy adults (BIG), including sex as an interaction term in the model, revealed no significant subtype-specific gene-wide associations. Using cross-trait meta-analysis of brain measures and psychiatric phenotypes, this study generated new hypotheses about specific links between genes, the brain and behavior. Results indicate that MECOM and AVPR1A may exert an effect on aggression through mechanisms involving nucleus accumbens and amygdala volumes, respectively.

Abstract

Understanding intraspecific variation in sociality is essential for characterizing the flexibility and evolution of social systems, yet its study in nonhuman animals is rare. Here, we investigated whether chimpanzees exhibit population-level differences in sociality that cannot be easily explained by differences in genetics or ecology. We compared social proximity and grooming tendencies across four semiwild populations of chimpanzees living in the same ecological environment over three consecutive years, using both linear mixed models and social network analysis. Results indicated temporally stable, population-level differences in dyadic-level sociality. Moreover, group cohesion measures capturing network characteristics beyond dyadic interactions (clustering, modularity, and social differentiation) showed population-level differences consistent with the dyadic indices. Subsequently, we explored whether the observed intraspecific variation in sociality could be attributed to cultural processes by ruling out alternative sources of variation including the influences of ecology, genetics, and differences in population demographics. We conclude that substantial variation in social behavior exists across neighboring populations of chimpanzees and that this variation is in part shaped by cultural processes.

Abstract

This study examines the prosody of focus in the Spanish of 16 Quechua-Spanish bilinguals near Cusco, Peru. Data come from a dialogue game that involved noun phrases consisting of a noun and an adjective. The questions in the game elicited broad focus, contrastive focus on the noun (non-final position) and contrastive focus on the adjective (final position). The phonetic analysis in Praat included peak alignment, peak height, local range and duration of the stressed syllable and word. The study revealed that Cusco Spanish differs from other Spanish varieties. In other Spanish varieties, contrastive focus is marked by early peak alignment, whereas broad focus involves a late peak on the non-final word. Furthermore, in other Spanish varieties contrastive focus is indicated by a higher F0 maximum, a wider local range, post-focal pitch reduction and a longer duration of the stressed syllable/word. For Cusco Spanish no phonological contrast between early and late peak alignment was found. However, peak alignment on the adjective in contrastive focus was significantly earlier than in the two other contexts. For women, similar results were found for the noun in contrastive focus. An additional prominence-lending feature marking contrastive focus concerned duration of the final word. Furthermore, the results revealed a higher F0 maximum for broad focus than for contrastive focus. The findings suggest a prosodic change, which is possibly due to contact with Quechua. The study contributes to research on information structure, prosody and contact-induced language change.

Abstract

In natural conversations, words are generally shorter and they often lack segments. It is unclear to what extent such durational and segmental reductions affect word recognition. The present study investigates to what extent reduction in the initial syllable hinders word comprehension, which types of segments listeners mostly rely on, and whether listeners use word duration as a cue in word recognition. We conducted three experiments in Dutch, in which we adapted the gating paradigm to study the comprehension of spontaneously uttered conversational speech by aligning the gates with the edges of consonant clusters or vowels. Participants heard the context and some segmental and/or durational information from reduced target words with unstressed initial syllables. The initial syllable varied in its degree of reduction, and in half of the stimuli the vowel was not clearly present. Participants gave too short answers if they were only provided with durational information from the target words, which shows that listeners are unaware of the reductions that can occur in spontaneous speech. More importantly, listeners required fewer segments to recognize target words if the vowel in the initial syllable was absent. This result strongly suggests that this vowel hardly plays a role in word comprehension, and that its presence may even delay this process. More important are the consonants and the stressed vowel.

Abstract

Insight in the developmental trajectory of the neuroanatomical reading correlates is important to understand related cognitive processes and disorders. In adults, a dual pathway model has been suggested encompassing a dorsal phonological and a ventral orthographic white matter system. This dichotomy seems not present in pre-readers, and the specific role of ventral white matter in reading remains unclear. Therefore, the present longitudinal study investigated the relation between ventral white matter and cognitive processes underlying reading in children with a broad range of reading skills (n = 61). Ventral pathways of the reading network were manually traced using diffusion tractography: the inferior fronto-occipital fasciculus (IFOF), inferior longitudinal fasciculus (ILF) and uncinate fasciculus (UF). Pathways were examined pre-reading (5–6 years) and after two years of reading acquisition (7–8 years). Dimension reduction for the cognitive measures resulted in one component for pre-reading cognitive measures and a separate phonological and orthographic component for the early reading measures. Regression analyses revealed a relation between the pre-reading cognitive component and bilateral IFOF and left ILF. Interestingly, exclusively the left IFOF was related to the orthographic component, whereas none of the pathways was related to the phonological component. Hence, the left IFOF seems to serve as the lexical reading route, already in the earliest reading stages.

Abstract

Learning often occurs in communicative and collaborative settings, yet almost all research into the neural basis of memory relies on participants encoding and retrieving information on their own. We investigated whether learning linguistic labels in a collaborative context at least partly relies on cognitively and neurally distinct representations, as compared to learning in an individual context. Healthy human participants learned labels for sets of abstract shapes in three different tasks. They came up with labels with another person in a collaborative communication task (collaborative condition), by themselves (individual condition), or were given pre-determined unrelated labels to learn by themselves (arbitrary condition). Immediately after learning, participants retrieved and produced the labels aloud during a communicative task in the MRI scanner. The fMRI results show that the retrieval of collaboratively generated labels as compared to individually learned labels engages brain regions involved in understanding others (mentalizing or theory of mind) and autobiographical memory, including the medial prefrontal cortex, the right temporoparietal junction and the precuneus. This study is the first to show that collaboration during encoding affects the neural networks involved in retrieval.

Abstract

Research into strategies that can combat episodic memory decline in healthy older adults has gained widespread attention over the years. Evidence suggests that a short period of rest immediately after learning can enhance memory consolidation, as compared to engaging in cognitive tasks. However, a recent study in younger adults has shown that post-encoding engagement in a working memory task leads to the same degree of memory consolidation as from post-encoding rest. Here, we tested whether this finding can be extended to older adults. Using a delayed recognition test, we compared the memory consolidation of word–picture pairs learned prior to 9 min of rest or a 2-Back working memory task, and examined its relationship with executive functioning and mindwandering propensity. Our results show that (1) similar to younger adults, memory for the word–picture associations did not differ when encoding was followed by post-encoding rest or 2-Back task and (2) older adults with higher mindwandering propensity retained more word–picture associations encoded prior to rest relative to those encoded prior to the 2-Back task, whereas participants with lower mindwandering propensity had better memory performance for the pairs encoded prior to the 2-Back task. Overall, our results indicate that the degree of episodic memory consolidation during both active and passive post-encoding periods depends on individual mindwandering tendency.

Abstract

During a post-encoding delay period, the ongoing consolidation of recently acquired memories can suffer interference if the delay period involves encoding of new memories, or sensory stimulation tasks. Interestingly, two recent independent studies suggest that (i) autobiographical thinking also interferes markedly with ongoing consolidation of recently learned wordlist material, while (ii) a 2-Back task might not interfere with ongoing consolidation, possibly due to the suppression of autobiographical thinking. In this study, we directly compare these conditions against a quiet wakeful rest baseline to test whether the promotion (via familiar sound-cues) or suppression (via a 2-Back task) of autobiographical thinking during the post-encoding delay period can affect consolidation of studied wordlists in a negative or a positive way, respectively. Our results successfully replicate previous studies and show a significant interference effect (as compared to the rest condition) when learning is followed by familiar sound-cues that promote autobiographical thinking, whereas no interference effect is observed when learning is followed by the 2-Back task. Results from a post-experimental experience-sampling questionnaire further show significant differences in the degree of autobiographical thinking reported during the three post-encoding periods: highest in the presence of sound-cues and lowest during the 2-Back task. In conclusion, our results suggest that varying levels of autobiographical thought during the post-encoding period may modulate episodic memory consolidation.

Abstract

The generation of subject–verb agreement is a central component of grammatical encoding. It is sensitive to conceptual and grammatical influences, but the interplay between these factors is still not fully understood. We investigate how semantic integration of the subject noun phrase (‘the secretary of/with the governor’) and the Local Noun Number (‘the secretary with the governor/governors’) affect the ease of selecting the verb form. Two hypotheses are assessed: according to the notional hypothesis, integration encourages the assignment of the singular notional number to the noun phrase and facilitates the choice of the singular verb form. According to the lexical interference hypothesis, integration strengthens the competition between nouns within the subject phrase, making it harder to select the verb form when the nouns mismatch in number. In two experiments, adult speakers of Dutch completed spoken preambles (Experiment 1) or selected appropriate verb forms (Experiment 2). Results showed facilitatory effects of semantic integration (fewer errors and faster responses with increasing integration). These effects did not interact with the effects of the Local Noun Number (slower response times and higher error rates for mismatching than for matching noun numbers). The findings thus support the notional hypothesis and a model of agreement where conceptual and lexical factors independently contribute to the determination of the number of the subject noun phrase and, ultimately, the verb.

Abstract

Compared to the large body of work on lexical access, little research has been done on grammatical encoding in language production. An exception is the generation of subject-verb agreement. Here, two key findings have been reported: (1) Speakers make more agreement errors when the head and local noun of a phrase mismatch in number than when they match (e.g., the key to the cabinet(s)); and (2) this attraction effect is asymmetric, with stronger attraction for singular than for plural head nouns. Although these findings are robust, the cognitive processes leading to agreement errors and their significance for the generation of correct agreement are not fully understood. We propose that future studies of agreement, and grammatical encoding in general, may benefit from using paradigms that tightly control the variability of the lexical content of the material. We report two experiments illustrating this approach. In both of them, the experimental items featured combinations of four nouns, four color adjectives, and two prepositions. In Experiment 1, native speakers of Dutch described pictures in sentences such as the circle next to the stars is blue. In Experiment 2, they carried out a forced-choice task, where they read subject noun phrases (e.g., the circle next to the stars) and selected the correct verb-phrase (is blue or are blue) with a button press. Both experiments showed an attraction effect, with more errors after subject phrases with mismatching, compared to matching head and local nouns. This effect was stronger for singular than plural heads, replicating the attraction asymmetry. In contrast, the response times recorded in Experiment 2 showed similar attraction effects for singular and plural head nouns. These results demonstrate that critical agreement phenomena can be elicited reliably in lexically-reduced contexts. We discuss the theoretical implications of the findings and the potential and limitations of studies using lexically simple materials.

Abstract

It has been shown that in Germanic languages (e.g. English, Dutch) phonemes are the primary (or proximate) planning units during the early stages of phonological encoding. Contrastingly, in Chinese and Japanese the phoneme does not seem to play an important role but rather the syllable (Chinese) and mora (Japanese) are essential. However, despite the lack of behavioral evidence, neurocorrelational studies in Chinese suggested that electrophysiological brain responses (i.e. preceding overt responses) may indicate some significance for the phoneme. We investigated this matter in Japanese and our data shows that unlike in Chinese (for which the literature shows mixed effects), in Japanese both the behavioral and neurocorrelational data indicate an important role only for the mora (and not the phoneme) during the early stages of phonological encoding.

Abstract

In English, Dutch, and other European languages, it is well established that the fundamental phonological unit in word production is the phoneme; in contrast, recent studies have shown that in Chinese it is the (atonal) syllable and in Japanese the mora. The present study investigated whether this cross-language variation in the size of the unit of word production is due to the type of script used in the language (i.e., alphabetic, morphosyllabic, or moraic). Capitalizing on the multiscriptal nature of Japanese, and using the Stroop color naming task, we show that the overlap in the initial mora between the color name and the written distractor facilitates color naming independent of script type. These results confirm the mora as the phonological unit of word production in Japanese, and establish the Stroop color naming task as a useful task for investigating the fundamental (or "proximate") phonological unit used in speech production.

Abstract

Language is a multi-faceted form of communication. It is not until recently though that language research moved on from simple stimuli and protocols toward a more ecologically valid approach, namely “shifting” from words and simple sentences to stories with varying degrees of contextual complexity. While much needed, the use of ecologically valid stimuli such as stories should also be explored in interactive rather than individualistic experimental settings leading the way to an interactive neuroscience of language. Indeed, mounting evidence suggests that cognitive processes and their underlying neural activity significantly differ between social and individual experiences. We aim at reviewing evidence, which indicates that the characteristics of linguistic and extra-linguistic contexts may significantly influence communication–including spoken language comprehension. In doing so, we provide evidence on the use of new paradigms and methodological advancements that may enable the study of complex language features in a truly interactive, ecological way.

Abstract

In a multi- and inter-cultural world, we daily encounter new words. Adult learners often rely on a situational context to learn and understand a new word's meaning. Here, we explored whether interactive learning facilitates word learning by directing the learner's attention to a correct new word referent when a situational context is non-informative. We predicted larger involvement of inferior parietal, frontal, and visual cortices involved in visuo-spatial attention during interactive learning. We scanned participants while they played a visual word learning game with and without a social partner. As hypothesized, interactive learning enhanced activity in the right Supramarginal Gyrus when the situational context provided little information. Activity in the right Inferior Frontal Gyrus during interactive learning correlated with post-scanning behavioral test scores, while these scores correlated with activity in the Fusiform Gyrus in the non-interactive group. These results indicate that attention is involved in interactive learning when the situational context is minimal and suggest that individual learning processes may be largely different from interactive ones. As such, they challenge the ecological validity of what we know about individual learning and advocate the exploration of interactive learning in naturalistic settings.

Abstract

Introduction

The atlas by Heinrich Sachs (1892) provided an accurate description of the intralobar fibres of the occipital lobe, with a detailed representation of the short associative tracts connecting different parts of the lobe. Little attention has been paid to the work of Sachs since its publication. In this study, we present the results of the dissection of three hemispheres, performed according to the Klingler technique (1935). Our anatomical findings are then compared to the original description of the occipital fibres anatomy as detailed by Sachs.
Methods

Three hemispheres were dissected according to Klingler's technique (1935). Specimens were fixed in 10% formalin and frozen at −15 °C for two weeks. After defreezing, dissection of the white matter fibres was performed with blunt dissectors. Coronal sections were obtained according to the cuts originally described by Sachs. In addition, medial to lateral and lateral to medial dissection of the white matter of the occipital lobe was also performed.

Results

A network of short association fibres was demonstrated in the occipital lobe, comprising intralobar association fibres and U-shaped fibres, which are connecting neighbouring gyri. Lateral to the ventricles, longitudinal fibres of the stratum sagittale were also identified that are arranged as external and internal layers. Fibres of the forceps major were also found to be in direct contact with the ventricular walls. We were able to replicate all tracts originally described by Sachs. In addition, a previously unrecognised tract, connecting the cuneus to the lingual gyrus, was identified. This tract corresponds to the “sledge runner”, described in tractography studies.

Conclusions

The occipital lobe shows a rich network of intralobar fibres, arranged around the ventricular wall. Good concordance was observed between the Klingler dissection technique and the histological preparations of Sachs.

Abstract

TANK-binding kinase 1 (TBK1) loss-of-function (LoF) mutations are known to cause frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS), often combined with memory deficits early in the disease course. We performed targeted resequencing of TBK1 in 1253 early onset Alzheimer's disease (EOAD) patients from 8 European countries to investigate whether pathogenic TBK1 mutations are enriched among patients with clinical diagnosis of EOAD. Variant frequencies were compared against 2117 origin-matched controls. We identified only 1 LoF mutation (p.Thr79del) in a patient clinically diagnosed with Alzheimer's disease and a positive family history of ALS. We did not observe enrichment of rare variants in EOAD patients compared to controls, nor of rare variants affecting NFκB induction. Of 3 common coding variants, rs7486100 showed evidence of association (OR 1.46 [95% CI 1.13–1.9]; p-value 0.01). Homozygous carriers of the risk allele showed reduced expression of TBK1 (p-value 0.03). Our findings are not indicative of a significant role for TBK1 mutations in EOAD. The association between common variants in TBK1, disease risk and reduced TBK1 expression warrants follow-up in FTD/ALS cohorts. © 2017 The Author(s)

Abstract

Over 25 genes are known to affect the risk of developing Alzheimer disease (AD), the most common neurodegenerative dementia. However, mechanistic insights and improved disease management remains limited, due to difficulties in determining the functional consequences of genetic associations. Transcriptomics is increasingly being used to corroborate or enhance interpretation of genetic discoveries. These approaches, which include second and third generation sequencing, single-cell sequencing, and bioinformatics, reveal allele-specific events connecting AD risk genes to expression profiles, and provide converging evidence of pathophysiological pathways underlying AD. Simultaneously, they highlight brain region- and cell-type-specific expression patterns, and alternative splicing events that affect the straightforward relation between a genetic variant and AD, re-emphasizing the need for an integrated approach of genetics and transcriptomics in understanding AD. © 2018 The Authors

Abstract

Interpreting polygenic overlap between ADHD and both literacy-related and language-related impairments is challenging as genetic associations might be influenced by indirectly shared genetic factors. Here, we investigate genetic overlap between polygenic ADHD risk and multiple literacy-related and/or language-related abilities (LRAs), as assessed in UK children (N ≤ 5919), accounting for genetically predictable educational attainment (EA). Genome-wide summary statistics on clinical ADHD and years of schooling were obtained from large consortia (N ≤ 326,041). Our findings show that ADHD-polygenic scores (ADHD-PGS) were inversely associated with LRAs in ALSPAC, most consistently with reading-related abilities, and explained ≤1.6% phenotypic variation. These polygenic links were then dissected into both ADHD effects shared with and independent of EA, using multivariable regressions (MVR). Conditional on EA, polygenic ADHD risk remained associated with multiple reading and/or spelling abilities, phonemic awareness and verbal intelligence, but not listening comprehension and non-word repetition. Using conservative ADHD-instruments (P-threshold < 5 × 10−8), this corresponded, for example, to a 0.35 SD decrease in pooled reading performance per log-odds in ADHD-liability (P = 9.2 × 10−5). Using subthreshold ADHD-instruments (P-threshold < 0.0015), these effects became smaller, with a 0.03 SD decrease per log-odds in ADHD risk (P = 1.4 × 10−6), although the predictive accuracy increased. However, polygenic ADHD-effects shared with EA were of equal strength and at least equal magnitude compared to those independent of EA, for all LRAs studied, and detectable using subthreshold instruments. Thus, ADHD-related polygenic links with LRAs are to a large extent due to shared genetic effects with EA, although there is evidence for an ADHD-specific association profile, independent of EA, that primarily involves literacy-related impairments.

Abstract

In an experimental study we explored the role of word frequency and orthographic constraints in the reading of Dutch bisyllabic words. Although Dutch orthography is highly regular, several deviations from a one-to-one correspondence occur. In polysyllabic words, the grapheme E may represent three different vowels: /ε /, /e/, or /œ /. In the experiment, skilled adult readers were presented lists of bisyllabic words containing the vowel E in the initial syllable and the same grapheme or another vowel in the second syllable. We expected word frequency to be related to word latency scores. On the basis of general word frequency data, we also expected the interpretation of the initial syllable as a stressed /e/ to be facilitated as compared to the interpretation of an unstressed /œ /. We found a strong negative correlation between word frequency and latency scores. Moreover, for words with E in either syllable we found a preference for a stressed /e/ interpretation, indicating a lexical frequency effect. The results are discussed with reference to a parallel dual-route model of word decoding.

Abstract

There are many different syntactic constructions that languages can use to encode motion events. In recent decades, great advances have been made in the description and study of these syntactic constructions from languages spoken around the world (Talmy 1985, 1991, Slobin 1996, 2004). However, relatively little attention has been paid to historical change in these systems (exceptions are Vincent 1999, Dufresne, Dupuis & Tremblay 2003, Kopecka 2006 and Peyraube 2006). In this article, diachronic change of motion event encoding systems in Indo-European is investigated using the available historical–comparative data and phylogenetic comparative methods adopted from evolutionary biology. It is argued that Proto-Indo-European was not satellite-framed, as suggested by Talmy (2007) and Acedo Matellán and Mateu (2008), but had a mixed motion event encoding system, as is suggested by the available historical–comparative data

Abstract

There have been opposing views on the possibility of a relationship between motion event encoding and the size of the path verb lexicon. Özçalışkan (2004) has proposed that verb-framed and satellite-framed languages should approximately have the same number of path verbs, whereas a review of some of the literature suggests that verb-framed languages typically have a bigger path verb lexicon than satelliteframed languages. In this article I demonstrate that evidence for this correlation can be found through phylogenetic comparative analysis of parallel corpus data from twenty Indo-European languages.

Abstract

The fruitless gene (fru) encodes a set of transcription factors (Fru) that display sexually dimorphic gene expression in the brain of the fruit-fly;Drosophila melanogaster . Behavioural studies have demonstrated that fru isessentialforcourtshipbehaviour inthemale flyandisthoughttoact bydirectingthe development of sex-specific neural circuitry that encodes this innate behavioural response. This study reports the identification of direct regulatory targets of the sexually dimorphic isoforms of the Fru protein using an in vitro model system. Genome wide binding sites were identified for each of the isoforms using Chromatin Immunoprecipitation coupled to deep sequencing (ChIP-Seq). Putative target genes were found to be involved in processes such as neurotransmission, ion-channel signalling and neuron development. All isoforms showed asignificant bias towards genes located on the X-chromosome,which may reflect a specific role for Fru in regulating x-linked genes. Taken together with expression analysis carried out in Fru positive neurons specifically isolated from the male fly brain, it appears that the Fru protein acts as a transcriptional activator. Understanding the regulatory cascades induced by Fru will help to shed light on the molecular mechanisms that are important for specification of neural circuitry underlying complex behaviour

Abstract

Strategies used in artificial grammar learning can shed light into the abilities of different species to extract regularities from the environment. In the A(X)nB rule, A and B items are linked, but assigned to different positional categories and separated by distractor items. Open questions are how widespread is the ability to extract positional regularities from A(X)nB patterns, which strategies are used to encode positional regularities and whether individuals exhibit preferences for absolute or relative position encoding. We used visual arrays to investigate whether cotton-top tamarins (Saguinusoedipus) can learn this rule and which strategies they use. After training on a subset of exemplars, two of the tested monkeys successfully generalized to novel combinations. These tamarins discriminated between categories of tokens with different properties (A, B, X) and detected a positional relationship between non-adjacent items even in the presence of novel distractors. The pattern of errors revealed that successful subjects used visual similarity with training stimuli to solve the task and that successful tamarins extracted the relative position of As and Bs rather than their absolute position, similarly to what has been observed in other species. Relative position encoding appears to be favoured in different tasks and taxa. Generalization, though, was incomplete, since we observed a failure with items that during training had always been presented in reinforced arrays, showing the limitations in grasping the underlying positional rule. These results suggest the use of local strategies in the extraction of positional rules in cotton-top tamarins.

Abstract

In bonobos, strong bonds have been documented between unrelated females and between mothers
and their adult sons, which can have important fitness benefits. Often age, sex or kinship similarity
have been used to explain social bond strength variation. Recent studies in other species also stress
the importance of personality, but this relationship remains to be investigated in bonobos. We used
behavioral observations on 39 adult and adolescent bonobos housed in 5 European zoos to study the
role of personality similarity in dyadic relationship quality. Dimension reduction analyses on individual
and dyadic behavioral scores revealed multidimensional personality (Sociability, Openness, Boldness,
Activity) and relationship quality components (value, compatibility). We show that, aside from
relatedness and sex combination of the dyad, relationship quality is also associated with personality
similarity of both partners. While similarity in Sociability resulted in higher relationship values, lower
relationship compatibility was found between bonobos with similar Activity scores. The results of this
study expand our understanding of the mechanisms underlying social bond formation in anthropoid
apes. In addition, we suggest that future studies in closely related species like chimpanzees should
implement identical methods for assessing bond strength to shed further light on the evolution of this
phenomenon.

Abstract

This study examines the influence of orthography on the processing of reduced word forms. For this purpose, we compared the impact of phonological variation with the impact of spelling-sound consistency on the processing of words that may be produced with or without the vowel schwa. Participants learnt novel French words in which the vowel schwa was present or absent in the first syllable. In Experiment 1, the words were consistently produced without schwa or produced in a variable manner (i.e., sometimes produced with and sometimes produced without schwa). In Experiment 2, words were always produced in a consistent manner, but an orthographic exposure phase was included in which words that were produced without schwa were either spelled with or without the letter . Results from naming and eye-tracking tasks suggest that both phonological variation and spelling-sound consistency influence the processing of spoken novel words. However, the influence of phonological variation outweighs the effect of spelling-sound consistency. Our findings therefore suggest that the influence of orthography on the processing of reduced word forms is relatively small.

Abstract

Semantic substitution errors (e.g., saying "arm" when "leg" is intended) are among the most common types of errors occurring during spontaneous speech. It has been shown that grammatical gender of German target nouns is preserved in the errors (E. Marx, 1999). In 3 experiments, the authors explored different accounts of the grammatical gender preservation effect in German. In all experiments, semantic substitution errors were induced using a continuous naming paradigm. In Experiment 1, it was found that gender preservation disappeared when speakers produced bare nouns. Gender preservation was found when speakers produced phrases with determiners marked for gender (Experiment 2) but not when the produced determiners were not marked for gender (Experiment 3). These results are discussed in the context of models of lexical retrieval during production.

Abstract

Navigation through familiar environments can rely upon distinct neural representations that are related to different memory systems with either the hippo-campus or the caudate nucleus at their core. However,it is a fundamental question whether and how these systems interact during route recognition. To address this issue, we combined a functional neuroimaging approach with a naturally occurring, well-controlled humanmodel of caudate nucleus dysfunction (i.e., pre-clinical and early-stage Huntington’s disease). Our results reveal a noncompetitive interaction so that the hippocampus compensates for gradual caudate nucleus dysfunction with a gradual activity increase,maintaining normal behavior. Furthermore, we revealed an interaction between medial temporal and caudate activity in healthy subjects, which was adaptively modified in Huntington patients to allow compensatory hippocampal processing. Thus, the two memory systems contribute in a noncompetitive, co operative manner to route recognition, which enables Polthe hippocampus to compensate seamlessly for the functional degradation of the caudate nucleus

Abstract

We meta‐analyzed the effectiveness of incidental second language word learning from spoken input. Our sample contained 105 effect sizes from 32 primary studies employing meaning‐focused word‐learning activities with 1,964 participants with typical cognitive functioning. The random‐effects meta‐analysis yielded a mean effect size of g = 1.05, reflecting generally large vocabulary gains from spoken input in meaning‐focused activities. A meta‐regression with three substantive and two methodological predictors also revealed that adult participants outperformed children in terms of word learning and that interactive learning tasks were more effective than noninteractive ones. Furthermore, learning scores were higher when measured with recognition than with recall tests. Methodologically, the use of a no‐input control group seemed to protect against an overestimation of learning effects, evidenced by smaller effect sizes. Finally, whether a pretest–posttest design was used did not influence effect sizes. All data and the analysis script are publicly available.

Abstract

This paper presents an overview of spatial deictic structures in Kata Kolok, a sign language which is indigenous to a Balinese village community. Sociolinguistic surveys and lexicographic comparisons have indicated that Kata Kolok is unrelated to the signing varieties in other parts of Bali and should be considered a sign language isolate as such. Kata Kolok emerged five generations ago and has been in intimate contact with spoken Balinese from its incipience. The findings from this paper suggest that this cross-modal contact has led to an absolute construction of the signing space, which is radically different in comparison to spatial deixis in other sign languages. Furthermore, Kata Kolok does not seem to have a class of true toponyms, but rather deploys deictic proto-toponyms. The Kata Kolok system on the whole does not exhibit any related linguistic forms or direct calques from spoken Balinese, and this suggests that the conceptual overlap between these two languages may have been facilitated by shared cultural practices as well as gestural communication rather than direct borrowings. Ultimately, this analysis challenges the very notion of a sign language isolate and suggests that Kata Kolok and other emergent signing varieties should be considered in light of the broader semiotic context in which they have evolved.

Abstract

ABSTRACTWe investigated to what extent L2 word learning in spoken interaction takes place when learners are unaware of taking part in a language learning study. Using a novel paradigm for approximating naturalistic (but not necessarily non-intentional) L2 learning in the lab, German learners of Dutch were led to believe that the study concerned judging the price of objects. Dutch target words (object names) were selected individually such that these words were unknown to the respective participant. Then, in a dialogue-like task with the experimenter, the participants were first exposed to and then tested on the target words. In comparison to a no-input control group, we observed a clear learning effect especially from the first two exposures, and better learning for cognates than for non-cognates, but no modulating effect of the exposure-production lag. Moreover, some of the acquired knowledge persisted over a six-month period.

Abstract

Noticing the hole (NTH) occurs when speakers want to say something, but realise they do not know the right word(s). Such awareness of lacking knowledge supposedly facilitates the acquisition of the unknown word(s) from later input (Swain, 1993). We tested this claim by experimentally inducing NTH in a second language (L2) for some participants (experimental), but not others (control). Then, in a price comparison game, all participants were exposed to spoken L2 input containing the to-be-learned words. They were unaware of taking part in an L2 study. Post-tests showed that participants who had noticed holes in their vocabulary had indeed learned more words compared to participants who had not. This held both for the experimental group as well as those participants in the control group who later reported to have noticed holes. Thus, when we become aware of vocabulary holes, the first step to improve our vocabulary is already taken.

Abstract

Hoe is de complexe taal van de mens ontstaan? Geleidelijk door natuurlijke selectie, omdat groeiende grammaticale vermogens voor de mens een evolutionair voordeel opleverden? Of plotseling, als onbedoeld bijproduct of neveneffect van een genetische mutatie, zonder dat er sprake is van een adaptief proces? In dit artikel zet ik de argumenten van Pinker en Bloom voor de eerste stelling tegenover argumenten van Chomsky en Gould voor de tweede stelling. Vervolgens laat ik zien dat deze twee extreme standpunten ruimte bieden voor andere opties, die nader onderzoek waard zijn. Zo kan genetisch onderzoek in de komende decennia informatie opleveren, die nuancering van beide standpunten noodzakelijk maakt.

Abstract

Metaphors occur frequently in literary texts. Deliberate Metaphor Theory (DMT; e.g., Steen, 2017) proposes that metaphors that serve a communicative function as metaphor are radically different from metaphors that do not have this function. We investigated differences in processing between deliberate and non-deliberate metaphors, compared to non-metaphorical words in literary reading. Using the Deliberate Metaphor Identification Procedure (Reijnierse et al., 2018), we identified metaphors in two literary stories. Then, eye-tracking was used to investigate participants’ (N = 72) reading behavior. Deliberate metaphors were read slower than non-deliberate metaphors, and both metaphor types were read slower than non-metaphorical words. Differences were controlled for several psycholinguistic variables. Differences in reading behavior were related to individual differences in reading experience and absorption and appreciation of the story. These results are in line with predictions from DMT and underline the importance of distinguishing between metaphor types in the experimental study of literary reading.

Abstract

Background Various CACNA1A missense mutations cause familial hemiplegic migraine type 1 (FHM1), a rare monogenic subtype of migraine with aura. FHM1 mutation R192Q is associated with pure hemiplegic migraine, whereas the S218L mutation causes hemiplegic migraine, cerebellar ataxia, seizures, and mild head trauma-induced brain edema. Transgenic knock-in (KI) migraine mouse models were generated that carried either the FHM1 R192Q or the S218L mutation and were shown to exhibit increased CaV2.1 channel activity. Here we investigated their cerebellar and caudal cortical transcriptome. Methods Caudal cortical and cerebellar RNA expression profiles from mutant and wild-type mice were studied using microarrays. Respective brain regions were selected based on their relevance to migraine aura and ataxia. Relevant expression changes were further investigated at RNA and protein level by quantitative polymerase chain reaction (qPCR) and/or immunohistochemistry, respectively. Results Expression differences in the cerebellum were most pronounced in S218L mice. Particularly, tyrosine hydroxylase, a marker of delayed cerebellar maturation, appeared strongly upregulated in S218L cerebella. In contrast, only minimal expression differences were observed in the caudal cortex of either mutant mice strain. Conclusion Despite pronounced consequences of migraine gene mutations at the neurobiological level, changes in cortical RNA expression in FHM1 migraine mice compared to wild-type are modest. In contrast, pronounced RNA expression changes are seen in the cerebellum of S218L mice and may explain their cerebellar ataxia phenotype

Abstract

The present study investigated the interplay between selective inhibition (the ability to suppress specific competing responses) and nonselective inhibition (the ability to suppress any inappropriate response) during single word production. To this end, we combined two well-established research paradigms: the picture-word interference task and the stop-signal task. Selective inhibition was assessed by instructing participants to name target pictures (e.g., dog) in the presence of semantically related (e.g., cat) or unrelated (e.g., window) distractor words. Nonselective inhibition was tested by occasionally presenting a visual stop-signal, indicating that participants should withhold their verbal response. The stop-signal was presented early (250 ms) aimed at interrupting the lexical selection stage, and late (325 ms) to influence the word-encoding stage of the speech production process. We found longer naming latencies for pictures with semantically related distractors than with unrelated distractors (semantic interference effect). The results further showed that, at both delays, stopping latencies (i.e., stop-signal RTs) were prolonged for naming pictures with semantically related distractors compared to pictures with unrelated distractors. Taken together, our findings suggest that selective and nonselective inhibition, at least partly, share a common inhibitory mechanism during different stages of the speech production process.

Abstract

Previous research has shown that inertial cues resulting from passive transport through a large environment do not necessarily facilitate acquiring knowledge about its layout. Here we examine whether the additional body-based cues that result from active movement facilitate the acquisition of spatial knowledge. Three groups of participants learned locations along an 840-m route. One group walked the route during learning, allowing access to body-based cues (i.e., vestibular, proprioceptive, and efferent information). Another group learned by sitting in the laboratory, watching videos made from the first group. A third group watched a specially made video that minimized potentially confusing head-on-trunk rotations of the viewpoint. All groups were tested on their knowledge of directions in the environment as well as on its configural properties. Having access to body-based information reduced pointing error by a small but significant amount. Regardless of the sensory information available during learning, participants exhibited strikingly common biases.

Abstract

Readers and listeners actively predict upcoming words during language processing. These predictions might serve to support the unification of incoming words into sentence context and thus rely on interactions between areas in the language network. In the current magnetoencephalography study, participants read sentences that varied in contextual constraints so that the predictability of the sentence-final words was either high or low. Before the sentence-final words, we observed stronger alpha power suppression for the highly compared with low constraining sentences in the left inferior frontal cortex, left posterior temporal region, and visual word form area. Importantly, the temporal and visual word form area alpha power correlated negatively with left frontal gamma power for the highly constraining sentences. We suggest that the correlation between alpha power decrease in temporal language areas and left prefrontal gamma power reflects the initiation of an anticipatory unification process in the language network.

Abstract

Using magnetoencephalography, the current study examined gamma activity associated with language prediction. Participants read high- and low-constraining sentences in which the final word of the sentence was either expected or unexpected. Although no consistent gamma power difference induced by the sentence-final words was found between the expected and unexpected conditions, the correlation of gamma power during the prediction and activation intervals of the sentence-final words was larger when the presented words matched with the prediction compared with when the prediction was violated or when no prediction was available. This suggests that gamma magnitude relates to the match between predicted and perceived words. Moreover, the expected words induced activity with a slower gamma frequency compared with that induced by unexpected words. Overall, the current study establishes that prediction is related to gamma power correlations and a slowing of the gamma frequency.

Abstract

The blocked cyclic naming paradigm has been increasingly employed to investigate the mechanisms underlying spoken word production. Semantic homogeneity typically elicits longer naming latencies than heterogeneity; however, it is debated whether competitive lexical selection or incremental learning underlies this effect. The current study manipulated both semantic and phonological homogeneity and used behavioural and electrophysiological measurements to provide evidence that can distinguish between the two accounts. Results show that naming latencies are longer in semantically homogeneous blocks, but shorter in phonologically homogeneous blocks, relative to heterogeneity. The semantic factor significantly modulates electrophysiological waveforms from 200 ms and the phonological factor from 350 ms after picture presentation. A positive component was demonstrated in both manipulations, possibly reflecting a task-related top-down bias in performing blocked cyclic naming. These results provide novel insights into the neural correlates of blocked cyclic naming and further contribute to the understanding of spoken word production.

Abstract

Neurodevelopmental disorders have a strong genetic component, but despite widespread efforts, the specific genetic factors underlying these disorders remain undefined for a large proportion of affected individuals. Given the accessibility of exome-sequencing, this problem has thus far been addressed from a protein-centric standpoint; however, protein-coding regions only make up ∼1-2% of the human genome. With the advent of whole-genome sequencing we are in the midst of a paradigm shift as it is now possible to interrogate the entire sequence of the human genome (coding and non-coding) to fill in the missing heritability of complex disorders. These new technologies bring new challenges, as the number of non-coding variants identified per individual can be overwhelming, making it prudent to focus on non-coding regions of known function, for which the effects of variation can be predicted and directly tested to assess pathogenicity. The 3’UTRome is a region of the non-coding genome that perfectly fulfils these criteria and is of high interest when searching for pathogenic variation related to complex neurodevelopmental disorders. Herein, we review the regulatory roles of the 3’UTRome as binding sites for microRNAs, RNA binding proteins or during alternative polyadenylation. We detail existing evidence that these regions contribute to neurodevelopmental disorders and outline strategies for identification and validation of novel putatively pathogenic variation in these regions. This evidence suggests that studying the 3’UTRome will lead to the identification of new risk factors, new candidate disease genes and a better understanding of the molecular mechanisms contributing to NDDs.

Abstract

Genome-wide association study results have yielded evidence for the association of common genetic variants with crude measures of completed educational attainment in adults. Whilst informative, these results do not inform as to the mechanism of these effects or their presence at earlier ages and where educational performance is more routinely and more precisely assessed. Single nucleotide polymorphisms exhibiting genome-wide significant associations with adult educational attainment were combined to derive an unweighted allele score in 5,979 and 6,145 young participants from the Avon Longitudinal Study of Parents and Children with key stage 3 national curriculum test results (SATS results) available at age 13 to 14 years in English and mathematics respectively. Standardised (z-scored) results for English and mathematics showed an expected relationship with sex, with girls exhibiting an advantage over boys in English (0.433 SD (95%CI 0.395, 0.470), p<10-10) with more similar results (though in the opposite direction) in mathematics (0.042 SD (95%CI 0.004, 0.080), p = 0.030). Each additional adult educational attainment increasing allele was associated with 0.041 SD (95%CI 0.020, 0.063), p = 1.79×10-04 and 0.028 SD (95%CI 0.007, 0.050), p = 0.01 increases in standardised SATS score for English and mathematics respectively. Educational attainment is a complex multifactorial behavioural trait which has not had heritable contributions to it fully characterised. We were able to apply the results from a large study of adult educational attainment to a study of child exam performance marking events in the process of learning rather than realised adult end product. Our results support evidence for common, small genetic contributions to educational attainment, but also emphasise the likely lifecourse nature of this genetic effect. Results here also, by an alternative route, suggest that existing methods for child examination are able to recognise early life variation likely to be related to ultimate educational attainment.

Abstract

Words which are expected to contain the same surface string of segments may, under identical prosodic circumstances, sometimes be realized with slight differences in duration. Some researchers have attributed such effects to differences in the words’ underlying forms (incomplete neutralization), while others have suggested orthographic influence and extremely careful speech as the cause. In this paper, we demonstrate such sub-phonemic durational differences in Dutch, a language which some past research has found not to have such effects. Past literature has also shown that listeners can often make use of incomplete neutralization to distinguish apparent homophones. We extend perceptual investigations of this topic, and show that listeners can perceive even durational differences which are not consistently observed in production. We further show that a difference which is primarily orthographic rather than underlying can also create such durational differences. We conclude that a wide variety of factors, in addition to underlying form, can induce speakers to produce slight durational differences which listeners can also use in perception.

Abstract

Twenty American English listeners identified gated fragments of all 2288 possible English within-word and cross-word diphones, providing a total of 538 560 phoneme categorizations. The results show orderly uptake of acoustic information in the signal and provide a view of where information about segments occurs in time. Information locus depends on each speech sound’s identity and phonological features. Affricates and diphthongs have highly localized information so that listeners’ perceptual accuracy rises during a confined time range. Stops and sonorants have more distributed and gradually appearing information. The identity and phonological features (e.g., vowel vs consonant) of the neighboring segment also influences when acoustic information about a segment is available. Stressed vowels are perceived significantly more accurately than unstressed vowels, but this effect is greater for lax vowels than for tense vowels or diphthongs. The dataset charts the availability of perceptual cues to segment identity across time for the full phoneme repertoire of English in all attested phonetic contexts.

Abstract

Background

Transcutaneous vagus nerve stimulation (tVNS) is a new, non-invasive technique being investigated as an intervention for a variety of clinical disorders, including epilepsy and depression. It is thought to exert its therapeutic effect by increasing central norepinephrine (NE) activity, but the evidence supporting this notion is limited.
Objective

In order to test for an impact of tVNS on psychophysiological and hormonal indices of noradrenergic function, we applied tVNS in concert with assessment of salivary alpha amylase (SAA) and cortisol, pupil size, and electroencephalograph (EEG) recordings.
Methods

Across three experiments, we applied real and sham tVNS to 61 healthy participants while they performed a set of simple stimulus-discrimination tasks. Before and after the task, as well as during one break, participants provided saliva samples and had their pupil size recorded. EEG was recorded throughout the task. The target for tVNS was the cymba conchae, which is heavily innervated by the auricular branch of the vagus nerve. Sham stimulation was applied to the ear lobe.
Results

P3 amplitude was not affected by tVNS (Experiment 1A: N=24; Experiment 1B: N=20; Bayes factor supporting null model=4.53), nor was pupil size (Experiment 2: N=16; interaction of treatment and time: p=0.79). However, tVNS increased SAA (Experiments 1A and 2: N=25) and attenuated the decline of salivary cortisol compared to sham (Experiment 2: N=17), as indicated by significant interactions involving treatment and time (p=.023 and p=.040, respectively).
Conclusion

These findings suggest that tVNS modulates hormonal indices but not psychophysiological indices of noradrenergic function.

Abstract

This article presents electrophysiological data on on-line syntactic processing during auditory sentence comprehension in patients with Broca's aphasia. Event-related brain potentials (ERPs) were recorded from the scalp while subjects listened to sentences that were either syntactically correct or contained violations of subject-verb agreement. Three groups of subjects were tested: Broca patients (n = 10), nonaphasic patients with a right-hemisphere (RH) lesion (n = 5), and healthy agedmatched controls (n = 12). The healthy, control subjects showed a P600/SPS effect as response to the agreement violations. The nonaphasic patients with an RH lesion showed essentially the same pattern. The overall group of Broca patients did not show this sensitivity. However, the sensitivity was modulated by the severity of the syntactic comprehension impairment. The largest deviation from the standard P600/SPS effect was found in the patients with the relatively more severe syntactic comprehension impairment. In addition, ERPs to tones in a classical tone oddball paradigm were also recorded. Similar to the normal control subjects and RH patients, the group of Broca patients showed a P300 effect in the tone oddball condition. This indicates that aphasia in itself does not lead to a general reduction in all cognitive ERP effects. It was concluded that deviations from the standard P600/SPS effect in the Broca patients reflected difficulties with on-line maintaining of number information across clausal boundaries for establishing subject-verb agreement.

Abstract

The establishment of a reliable model for the study of Purkinje cells in vitro is of particular importance, given their central role in cerebellar function and pathology. Recent advances in induced pluripotent stem cell (iPSC) technology offer the opportunity to generate multiple neuronal subtypes for study in vitro. However, to date, only a handful of studies have generated Purkinje cells from human pluripotent stem cells, with most of these protocols proving challenging to reproduce. Here, we describe a simplified method for the reproducible generation of Purkinje cells from human iPSCs. After 21 days of treatment with factors selected to mimic the self-inductive properties of the isthmic organiser—insulin, fibroblast growth factor 2 (FGF2), and the transforming growth factor β (TGFβ)-receptor blocker SB431542—hiPSCs could be induced to form En1-positive cerebellar progenitors at efficiencies of up to 90%. By day 35 of differentiation, subpopulations of cells representative of the two cerebellar germinal zones, the rhombic lip (Atoh1-positive) and ventricular zone (Ptf1a-positive), could be identified, with the latter giving rise to cells positive for Purkinje cell progenitor-specific markers, including Lhx5, Kirrel2, Olig2 and Skor2. Further maturation was observed following dissociation and co-culture of these cerebellar progenitors with mouse cerebellar cells, with 10% of human cells staining positive for the Purkinje cell marker calbindin by day 70 of differentiation. This protocol, which incorporates modifications designed to enhance cell survival and maturation and improve the ease of handling, should serve to make existing models more accessible, in order to enable future advances in the field.

Abstract

Four eye-tracking experiments examined lexical competition in non-native spoken-word recognition. Dutch listeners hearing English fixated longer on distractor pictures with names containing vowels that Dutch listeners are likely to confuse with vowels in a target picture name (pencil, given target panda) than on less confusable distractors (beetle, given target bottle). English listeners showed no such viewing time difference. The confusability was asymmetric: given pencil as target, panda did not distract more than distinct competitors. Distractors with Dutch names phonologically related to English target names (deksel, ‘lid,’ given target desk) also received longer fixations than distractors with phonologically unrelated names. Again, English listeners showed no differential effect. With the materials translated into Dutch, Dutch listeners showed no activation of the English words (desk, given target deksel). The results motivate two conclusions: native phonemic categories capture second-language input even when stored representations maintain a second-language distinction; and lexical competition is greater for non-native than for native listeners.

Abstract

New linguistic information must be integrated into our existing language system. Using a novel experimental task that incorporates a syntactic priming paradigm into artificial language learning, we investigated how new grammatical regularities and words are learned. This innovation allowed us to control the language input the learner received, while the syntactic priming paradigm provided insight into the nature of the underlying syntactic processing machinery. The results of the present study pointed to facilitatory syntactic processing effects within the first days of learning: Syntactic and lexical priming effects revealed participants’ sensitivity to both novel words and word orders. This suggested that novel syntactic structures and their meaning (form–function mapping) can be acquired rapidly through incidental learning. More generally, our study indicated similar mechanisms for learning and processing in both artificial and natural languages, with implications for the relationship between first and second language learning.

Abstract

Introduction
Words are not processed in isolation but in rich contexts that are used to modulate and facilitate language comprehension. Here, we investigate distinct neural networks underlying two types of contexts, the current linguistic environment and verb‐based syntactic preferences.

Methods
We had two main manipulations. The first was the current linguistic environment, where the relative frequencies of two syntactic structures (prepositional object [PO] and double‐object [DO]) would either follow everyday linguistic experience or not. The second concerned the preference toward one or the other structure depending on the verb; learned in everyday language use and stored in memory. German participants were reading PO and DO sentences in German while brain activity was measured with functional magnetic resonance imaging.

Results
First, the anterior cingulate cortex (ACC) showed a pattern of activation that integrated the current linguistic environment with everyday linguistic experience. When the input did not match everyday experience, the unexpected frequent structure showed higher activation in the ACC than the other conditions and more connectivity from the ACC to posterior parts of the language network. Second, verb‐based surprisal of seeing a structure given a verb (PO verb preference but DO structure presentation) resulted, within the language network (left inferior frontal and left middle/superior temporal gyrus) and the precuneus, in increased activation compared to a predictable verb‐structure pairing.

Conclusion
In conclusion, (1) beyond the canonical language network, brain areas engaged in prediction and error signaling, such as the ACC, might use the statistics of syntactic structures to modulate language processing, (2) the language network is directly engaged in processing verb preferences. These two networks show distinct influences on sentence processing.

Abstract

Two cross-modal priming experiments examined two questions about word recognition in foreign-accented speech: Does accent adaptation occur only for genuine accents markers, and does adaptation depend on language experience? We compared recognition of words spoken with canonical, genuinely-accented and arbitrarily-accented vowels. In Experiment 1, an Italian speaker pronounced vowels in English prime words canonically, or by lengthening /ɪ/ as in a genuine Italian accent (*/tri:k/ for trick), or by arbitrarily shortening /i:/ (*/trɪt/ for treat). Lexical-decision times to subsequent visual target words showed different priming effects in three listener groups. Monolingual native English listeners recognized variants with lengthened but not shortened vowels. Bilingual nonnative Italian-English listeners, who could not reliably distinguish vowel length, recognized both variants. Bilingual nonnative Dutch-English listeners also recognized both variants. In Experiment 2, bilingual Dutch-English listeners recognized Dutch words with genuinely- and arbitrarily-accented vowels (spoken by a native Italian with lengthened and shortened vowels respectively), but recognized words with canonical vowels more easily than words with accented vowels. These results suggest that adaptation to genuine accent markers arises for monolingual and bilingual listeners alike and can occur in native and nonnative languages, but that bilinguals can adapt to arbitrary accent markers better than monolinguals.

Abstract

Reports of an advantage of bilingualism on brain structure in young adult participants
are inconsistent. Abutalebi et al. (2012) reported more efficient monitoring of conflict during the
Flanker task in young bilinguals compared to young monolingual speakers. The present study
compared young adult (mean age = 24) Cantonese-English bilinguals in Hong Kong and young
adult monolingual speakers. We expected (a) differences in metabolites in neural tissue to result
from bilingual experience, as measured by 1H-MRS at 3T, (b) correlations between metabolic
levels and Flanker conflict and interference effects (c) different associations in bilingual and
monolingual speakers. We found evidence of metabolic differences in the ACC due to bilingualism,
specifically in metabolites Cho, Cr, Glx and NAA. However, we found no significant correlations
between metabolic levels and conflict and interference effects and no significant evidence of
differential relationships between bilingual and monolingual speakers. Furthermore, we found no
evidence of significant differences in the mean size of conflict and interference effects between
groups i.e. no bilingual advantage. Lower levels of Cho, Cr, Glx and NAA in bilingual adults
compared to monolingual adults suggest that the brains of bilinguals develop greater adaptive
control during conflict monitoring because of their extensive bilingual experience.

Abstract

Humans differ widely in their navigational abilities. Studies have shown that self-reports on navigational abilities are good predictors of performance on navigation tasks in real and virtual environments. The caudate nucleus and medial temporal lobe regions have been suggested to subserve different navigational strategies. The ability to use different strategies might underlie navigational ability differences. This study examines the anatomical correlates of self-reported navigational ability in both gray and white matter. Local gray matter volume was compared between a group (N = 134) of good and bad navigators using voxel-based morphometry (VBM), as well as regional volumes. To compare between good and bad navigators, we also measured white matter anatomy using diffusion tensor imaging (DTI) and looked at fractional anisotropy (FA) values. We observed a trend toward higher local GM volume in right anterior parahippocampal/rhinal cortex for good versus bad navigators. Good male navigators showed significantly higher local GM volume in right hippocampus than bad male navigators. Conversely, bad navigators showed increased FA values in the internal capsule, the white matter bundle closest to the caudate nucleus and a trend toward higher local GM volume in the caudate nucleus. Furthermore, caudate nucleus regional volume correlated negatively with navigational ability. These convergent findings across imaging modalities are in line with findings showing that the caudate nucleus and the medial temporal lobes are involved in different wayfinding strategies. Our study is the first to show a link between self-reported large-scale navigational abilities and different measures of brain anatomy.

Abstract

Studies on metacognition have shown that participants can report on their performance on a wide range of perceptual, memory and behavioral tasks. We know little, however, about the ability to report on one's attentional focus. The degree and direction of somatosensory attention can, however, be readily discerned through suppression of alpha band frequencies in EEG/MEG produced by the somatosensory cortex. Such top-down attentional modulations of cortical excitability have been shown to result in better discrimination performance and decreased response times. In this study we asked whether the degree of attentional focus is also accessible for subjective report, and whether such evaluations correspond to the amount of somatosensory alpha activity. In response to auditory cues participants maintained somatosensory attention to either their left or right hand for intervals varying randomly between 5 and 32seconds, while their brain activity was recorded with MEG. Trials were terminated by a probe sound, to which they reported their level of attention on the cued hand right before probe-onset. Using a beamformer approach, we quantified the alpha activity in left and right somatosensory regions, one second before the probe. Alpha activity from contra- and ipsilateral somatosensory cortices for high versus low attention trials were compared. As predicted, the contralateral somatosensory alpha depression correlated with higher reported attentional focus. Finally, alpha activity two to three seconds before the probe-onset was correlated with attentional focus. We conclude that somatosensory attention is indeed accessible to metacognitive awareness.

Abstract

Left-handers are often excluded from study cohorts in neuroscience and neurogenetics in order to reduce variance in the data. However, recent investigations have shown that the inclusion or targeted recruitment of left-handers can be informative in studies on a range of topics, such as cerebral lateralization and the genetic underpinning of asymmetrical brain development. Left-handed individuals represent a substantial portion of the human population and therefore left-handedness falls within the normal range of human diversity; thus, it is important to account for this variation in our understanding of brain functioning. We call for neuroscientists and neurogeneticists to recognize the potential of studying this often-discarded group of research subjects.

Abstract

While most people prefer to use their right hand to brush their teeth, throw a ball, or hold a tennis racket, left-handers prefer to use their left hand. This is the case for around 10 per cent of all people. There was a time (not so long ago) when left-handers were stigmatized in Western (and other) communities: it was considered a bad sign if you were left-handed, and left-handed children were often forced to write with their right hand. This is nonsensical: there is nothing wrong with being left-handed, and trying to write with the non-preferred hand is frustrating for almost everybody. As a matter of fact, science can learn from left-handers, and in this paper, we discuss how this may be the case. We review why some people are left-handed and others are not, how left-handers' brains differ from right-handers’, and why scientists study left-handedness in the first place

Abstract

Background

The biological mechanisms of headache chronification are poorly understood. We aimed to identify changes in DNA methylation associated with the transformation from episodic to chronic headache.
Methods

Participants were recruited from the population-based Norwegian HUNT Study. Thirty-six female headache patients who transformed from episodic to chronic headache between baseline and follow-up 11 years later were matched against 35 controls with episodic headache. DNA methylation was quantified at 485,000 CpG sites, and changes in methylation level at these sites were compared between cases and controls by linear regression analysis. Data were analyzed in two stages (Stages 1 and 2) and in a combined meta-analysis.
Results

None of the top 20 CpG sites identified in Stage 1 replicated in Stage 2 after multiple testing correction. In the combined meta-analysis the strongest associated CpG sites were related to SH2D5 and NPTX2, two brain-expressed genes involved in the regulation of synaptic plasticity. Functional enrichment analysis pointed to processes including calcium ion binding and estrogen receptor pathways.
Conclusion

In this first genome-wide study of DNA methylation in headache chronification several potentially implicated loci and processes were identified. The study exemplifies the use of prospectively collected population cohorts to search for epigenetic mechanisms of disease

Abstract

Researchers have suggested that the vocabularies of languages are oriented towards the communicative needs of language users. Here, we provide evidence demonstrating that the higher frequency of visual words in a large variety of English corpora is reflected in greater lexical differentiation—a greater number of unique words—for the visual domain in the English lexicon. In comparison, sensory modalities that are less frequently talked about, particularly taste and smell, show less lexical differentiation. In addition, we show that even though sensory language can be expected to change across historical time and between contexts of use (e.g., spoken language versus fiction), the pattern of visual dominance is a stable property of the English language. Thus, we show that across the board, precisely those semantic domains that are more frequently talked about are also more lexically differentiated, for perceptual experiences. This correlation between type and token frequencies suggests that the sensory lexicon of English is geared towards communicative efficiency.

Abstract

Vocal learning is a behavioral trait in which the social and acoustic environment shapes the vocal repertoire of individuals. Over the past century, the study of vocal learning has progressed at the intersection of ecology, physiology, neuroscience, molecular biology, genomics, and evolution. Yet, despite the complexity of this trait, vocal learning is frequently described as a binary trait, with species being classified as either vocal learners or vocal non-learners. As a result, studies have largely focused on a handful of species for which strong evidence for vocal learning exists. Recent studies, however, suggest a continuum in vocal learning capacity across taxa. Here, we further suggest that vocal learning is a multi-component behavioral phenotype comprised of distinct yet interconnected modules. Discretizing the vocal learning phenotype into its constituent modules would facilitate integration of findings across a wider diversity of species, taking advantage of the ways in which each excels in a particular module, or in a specific combination of features. Such comparative studies can improve understanding of the mechanisms and evolutionary origins of vocal learning. We propose an initial set of vocal learning modules supported by behavioral and neurobiological data and highlight the need for diversifying the field in order to disentangle the complexity of the vocal learning phenotype.