Publications

Abstract

Spinocerebellar ataxia type 23 (SCA23) is a late‐onset neurodegenerative disorder characterized by slowly progressive gait and limb ataxia, for which there is no therapy available. It is caused by pathogenic variants in PDYN, which encodes prodynorphin (PDYN). PDYN is processed into the opioid peptides α‐neoendorphin and dynorphins (Dyn) A and B; inhibitory neurotransmitters that function in pain signaling, stress‐induced responses and addiction. Variants causing SCA23 mostly affect Dyn A, leading to loss of secondary structure and increased peptide stability. PDYNR212W mice express human PDYN containing the SCA23 variant p.R212W. These mice show progressive motor deficits from 3 months of age, climbing fiber (CF) deficits from 3 months of age, and Purkinje cell (PC) loss from 12 months of age. A mouse model for SCA1 showed similar CF deficits, and a recent study found additional developmental abnormalities, namely increased GABAergic interneuron connectivity and non‐cell autonomous disruption of PC function. As SCA23 mice show a similar pathology to SCA1 mice in adulthood, we hypothesized that SCA23 may also follow SCA1 pathology during development. Examining PDYNR212W cerebella during development, we uncovered developmental deficits from 2 weeks of age, namely a reduced number of GABAergic synapses on PC soma, possibly leading to the observed delay in early phase CF elimination between 2 and 3 weeks of age. Furthermore, CFs did not reach terminal height, leaving proximal PC dendrites open to be occupied by parallel fibers (PFs). The observed increase in vGlut1 protein—a marker for PF‐PC synapses—indicates that PFs indeed take over CF territory and have increased connectivity with PCs. Additionally, we detected altered expression of several critical Ca2+ channel subunits, potentially contributing to altered Ca2+ transients in PDYNR212W cerebella. These findings indicate that developmental abnormalities contribute to the SCA23 pathology and uncover a developmental role for PDYN in the cerebellum.

Abstract

Orthographic systems vary dramatically in the extent to which they encode a language’s phonological and lexico-semantic structure. Studies of the effects of orthographic transparency suggest that such variation is likely to have major implications for how the reading system operates. However, such studies have been unable to examine in isolation the contributory effect of transparency on reading due to co-varying linguistic or socio-cultural factors. We first investigated the phonological properties of languages using the range of the world’s orthographic systems (alphabetic; alphasyllabic; consonantal; syllabic; logographic), and found that, once geographical proximity is taken into account, phonological properties do not relate to orthographic system. We then explored the processing implications of orthographic variation by training a connectionist implementation of the triangle model of reading on the range of orthographic systems whilst controlling for phonological and semantic structure. We show that the triangle model is effective as a universal model of reading, able to replicate key behavioural and neuroscientific results. Importantly, the model also generates new predictions deriving from an explicit description of the effects of orthographic transparency on how reading is realised and defines the consequences of orthographic systems on reading processes.

Abstract

SATB2-associated syndrome (SAS) is a neurodevelopmental disorder caused by heterozygous pathogenic variants in the SATB2 gene, and is typically characterized by intellectual disability and severely impaired communication skills. The goal of this study was to contribute to the understanding of speech and language impairments in SAS, in the context of general developmental skills and cognitive and adaptive functioning. We performed detailed oral motor, speech and language profiling in combination with neuropsychological assessments in 23 individuals with a molecularly confirmed SAS diagnosis: 11 primarily verbal individuals and 12 primarily nonverbal individuals, independent of their ages. All individuals had severe receptive language delays. For all verbal individuals, we were able to define underlying speech conditions. While childhood apraxia of speech was most prevalent, oral motor problems appeared frequent as well and were more present in the nonverbal group than in the verbal group. For seven individuals, age-appropriate Wechsler indices could be derived, showing that the level of intellectual functioning of these individuals varied from moderate–mild ID to mild ID-borderline intellectual functioning. Assessments of adaptive functioning with the Vineland Screener showed relatively high scores on the domain “daily functioning” and relatively low scores on the domain “communication” in most individuals. Altogether, this study provides a detailed delineation of oral motor, speech and language skills and neuropsychological functioning in individuals with SAS, and can provide families and caregivers with information to guide diagnosis, management and treatment approaches.

Abstract

Heterozygous pathogenic variants in various FOXP genes cause specific developmental disorders. The phenotype associated with heterozygous variants in FOXP4 has not been previously described.
We assembled a cohort of eight individuals with heterozygous and mostly de novo variants in FOXP4: seven individuals with six different missense variants and one individual with a frameshift variant. We collected clinical data to delineate the phenotypic spectrum, and used in silico analyses and functional cell-based assays to assess pathogenicity of the variants.
We collected clinical data for six individuals: five individuals with a missense variant in the forkhead box DNA-binding domain of FOXP4, and one individual with a truncating variant. Overlapping features included speech and language delays, growth abnormalities, congenital diaphragmatic hernia, cervical spine abnormalities, and ptosis. Luciferase assays showed loss-of-function effects for all these variants, and aberrant subcellular localization patterns were seen in a subset. The remaining two missense variants were located outside the functional domains of FOXP4, and showed transcriptional repressor capacities and localization patterns similar to the wild-type protein.
Collectively, our findings show that heterozygous loss-of-function variants in FOXP4 are associated with an autosomal dominant neurodevelopmental disorder with speech/language delays, growth defects, and variable congenital abnormalities.

Abstract

Recent studies of aging organisms have identified a systematic phenomenon, characterized by a negative correlation between gene length and their expression in various cell types, species, and diseases. We term this phenomenon gene-length-dependent transcription decline (GLTD) and suggest that it may represent a bottleneck in the transcription machinery and thereby significantly contribute to aging as an etiological factor. We review potential links between GLTD and key aging processes such as DNA damage and explore their potential in identifying disease modification targets. Notably, in Alzheimer’s disease, GLTD spotlights extremely long synaptic genes at chromosomal fragile sites (CFSs) and their vulnerability to postmitotic DNA damage. We suggest that GLTD is an integral element of biological aging.

Abstract

Low-frequency 1q21.1 distal deletion and duplication copy number variant (CNV) carriers are predisposed to multiple neurodevelopmental disorders, including schizophrenia, autism and intellectual disability. Human carriers display a high prevalence of micro- and macrocephaly in deletion and duplication carriers, respectively. The underlying brain structural diversity remains largely unknown. We systematically called CNVs in 38 cohorts from the large-scale ENIGMA-CNV collaboration and the UK Biobank and identified 28 1q21.1 distal deletion and 22 duplication carriers and 37,088 non-carriers (48% male) derived from 15 distinct magnetic resonance imaging scanner sites. With standardized methods, we compared subcortical and cortical brain measures (all) and cognitive performance (UK Biobank only) between carrier groups also testing for mediation of brain structure on cognition. We identified positive dosage effects of copy number on intracranial volume (ICV) and total cortical surface area, with the largest effects in frontal and cingulate cortices, and negative dosage effects on caudate and hippocampal volumes. The carriers displayed distinct cognitive deficit profiles in cognitive tasks from the UK Biobank with intermediate decreases in duplication carriers and somewhat larger in deletion carriers—the latter potentially mediated by ICV or cortical surface area. These results shed light on pathobiological mechanisms of neurodevelopmental disorders, by demonstrating gene dose effect on specific brain structures and effect on cognitive function.

Abstract

We present results from cross-modal priming experiments on German participles and noun plurals. The experiments produced parallel results for both inflectional systems. Regular inflection exhibits full priming whereas irregularly inflected word forms show only partial priming: after hearing regularly inflected words (-t participles and -s plurals), lexical decision times on morphologically related word forms (presented visually) were similar to reaction times for a base-line condition in which prime and target were identical, but significantly shorter than in a control condition where prime and target were unrelated. In contrast, prior presentation of irregular words (-n participles and -er plurals) led to significantly longer response times on morphologically related word forms than the prior presentation of the target itself. Hence, there are clear priming differences between regularly and irregularly inflected German words. We compare the findings on German with experimental results on regular and irregular inflection in English and Italian, and discuss theoretical implications for single versus dual-mechanism models of inflection.

Abstract

Do we structure object-related conceptual information according to real-world sensorimotor experience, or can it also be shaped by linguistic information? This study investigates whether a feature of language coded in grammar—numeral classifiers—affects the conceptual representation of objects. We compared speakers of Mandarin (a classifier language) with speakers of Dutch (a language without classifiers) on how they judged object similarity in four studies. In the first three studies, participants had to rate how similar a target object was to four comparison objects, one of which shared a classifier with the target. Objects were presented as either words or pictures. Overall, the target object was always rated as most similar to the object with the shared classifier, but this was the case regardless of the language of the participant. In a final study employing a successive pile-sorting task, we also found that the underlying object concepts were similar for speakers of Mandarin and Dutch. Speakers of a non-classifier language are therefore sensitive to the same conceptual similarities that underlie classifier systems in a classifier language. Classifier systems may therefore reflect conceptual structure, rather than shape it.

Abstract

Spoken word recognition involves automatic activation of lexical candidates compatible with the perceived input. In running speech, words abut one another without intervening gaps, and syllable boundaries can mismatch with word boundaries. For instance, liaison in ’petit agneau’ creates a syllable beginning with a consonant although ’agneau’ begins with a vowel. In two cross-modal priming experiments we investigate how French listeners recognise words in liaison environments. These results suggest that the resolution of liaison in part depends on acoustic cues which distinguish liaison from non-liaison consonants, and in part on the availability of lexical support for a liaison interpretation.

Abstract

We present the first ERP experiments that test the online processing of the scalar implicature some ⇝ not all in contexts where the speaker competence assumption is violated. Participants observe game scenarios with four open cards on the table and two closed cards outside of the table, while listening to statements made by a virtual player. In the full access context, the player makes a fully informed statement by referring only to the open cards, as cards on the table; in the partial access context, she makes a partially informed statement by referring to the whole set of cards, as cards in the game. If all of the open cards contain a given object X (Fullset condition), then some cards on the table contain Xs is inconsistent with the not all reading, whereas it is unknown whether some cards in the game contain X is consistent with this reading. If only a subset of the open cards contains X (Subset condition), then both utterances are known to be consistent with the not all implicature. Differential effects are observed depending on the quantifier reading adopted by the participant: For those participants who adopt the not all reading in the full access context, but not in the partial access context (weak pragmatic reading), a late posterior negativity effect is observed in the partial access context for the Fullset relative to the Subset condition. This effect is argued to reflect inference-driven context retrieval and monitoring processes related to epistemic reasoning involved in evaluating the competence assumption. By contrast, for participants who adopt the logical interpretation of some (some and possibly all), an N400 effect is observed in the partial access context, when comparing the Subset against the Fullset condition, which is argued to result from the competition between the two quantifying expressions some cards on the table and some cards in the game functioning in the experiment as scalar alternatives.

Abstract

Purpose: When we speak, we gesture, and indeed, persons with aphasia gesture more frequently. The reason(s) for this is still being investigated, spurring an increase in the number of studies of gesture in persons with aphasia. As the number of studies increases, so too does the need for a shared set of best practices for gesture research in aphasia. After briefly reviewing the importance and use of gesture in persons with aphasia, this viewpoint puts forth methodological and design considerations when evaluating gesture in persons with aphasia.
Method & Results: We explore several different design and methodological considerations for gesture research specific to persons with aphasia, such as video angle specifications, data collection techniques, and analysis considerations. The goal of these suggestions is to develop transparent and reproducible methods for evaluating gesture in aphasia to build a solid foundation for continued work in this area.
Conclusions: We have proposed that it is critical to evaluate multimodal communication in a methodologically robust way to facilitate increased knowledge about the relationship of gesture to spoken language, cognition, and to other aspects of living with aphasia and recovery from aphasia. We conclude by postulating future directions for gesture research in aphasia.

Abstract

Abstract Objective Paroxysmal epileptiform abnormalities on electroencephalography (EEG) are the hallmark of epilepsies, but it is uncertain to what extent epilepsy and background EEG oscillations share neurobiological underpinnings. Here, we aimed to assess the genetic correlation between epilepsy and background EEG oscillations. Methods Confounding factors, including the heterogeneous etiology of epilepsies and medication effects, hamper studies on background brain activity in people with epilepsy. To overcome this limitation, we compared genetic data from a genome-wide association study (GWAS) on epilepsy (n = 12 803 people with epilepsy and 24 218 controls) with that from a GWAS on background EEG (n = 8425 subjects without epilepsy), in which background EEG oscillation power was quantified in four different frequency bands: alpha, beta, delta, and theta. We replicated our findings in an independent epilepsy replication dataset (n = 4851 people with epilepsy and 20 428 controls). To assess the genetic overlap between these phenotypes, we performed genetic correlation analyses using linkage disequilibrium score regression, polygenic risk scores, and Mendelian randomization analyses. Results Our analyses show strong genetic correlations of genetic generalized epilepsy (GGE) with background EEG oscillations, primarily in the beta frequency band. Furthermore, we show that subjects with higher beta and theta polygenic risk scores have a significantly higher risk of having generalized epilepsy. Mendelian randomization analyses suggest a causal effect of GGE genetic liability on beta oscillations. Significance Our results point to shared biological mechanisms underlying background EEG oscillations and the susceptibility for GGE, opening avenues to investigate the clinical utility of background EEG oscillations in the diagnostic workup of epilepsy.

Abstract

Relying on the methodology of conversation analysis, this article examines a practice in ordinary conversation characterized by the resaying of a word, phrase, or sentence. The article shows that multiple sayings such as "No no no" or "Alright alright alright" are systematic in both their positioning relative to the interlocutor's talk and in their function. Specifically, the findings are that multiple sayings are a resource speakers have to display that their turn is addressing an in progress course of action rather than only the just prior utterance. Speakers of multiple sayings communicate their stance that the prior speaker has persisted unnecessarily in the prior course of action and should properly halt course of action.

Abstract

Social interaction is organized around norms and preferences that guide our construction of actions and our interpretation of those of others, creating a reflexive moral order. Sociological theory suggests two possibilities for the type of moral order that underlies the policing of interactional norm and preference violations: a morality that focuses on the nature of violations themselves and a morality that focuses on the positioning of actors as they maintain their conduct comprehensible, even when they depart from norms and preferences. We find that actors are more likely to reproach interactional violations for which an account is not provided by the transgressor, and that actors weakly reproach or let pass first offenses while more strongly policing violators who persist in bad behavior. Based on these findings, we outline a theory of interactional policing that rests not on the nature of the violation but rather on actors' moral positioning.

Abstract

Lesch-Nyhan disease (LND) is an inherited disorder caused by pathogenic variants in the HPRT1 gene, which encodes the purine recycling enzyme hypoxanthine–guanine phosphoribosyltransferase (HGprt). We generated 6 induced pluripotent stem cell (iPSC) lines from 3 individuals with LND, along with 6 control lines from 3 normal individuals. All 12 lines had the characteristics of pluripotent stem cells, as assessed by immunostaining for pluripotency markers, expression of pluripotency genes, and differentiation into the 3 primary germ cell layers. Gene expression profiling with RNAseq demonstrated significant heterogeneity among the lines. Despite this heterogeneity, several anticipated abnormalities were readily detectable across all LND lines, including reduced HPRT1 mRNA. Several unexpected abnormalities were also consistently detectable across the LND lines, including decreases in FAR2P1 and increases in RNF39. Shotgun proteomics also demonstrated several expected abnormalities in the LND lines, such as absence of HGprt protein. The proteomics study also revealed several unexpected abnormalities across the LND lines, including increases in GNAO1 decreases in NSE4A. There was a good but partial correlation between abnormalities revealed by the RNAseq and proteomics methods. Finally, functional studies demonstrated LND lines had no HGprt enzyme activity and resistance to the toxic pro-drug 6-thioguanine. Intracellular purines in the LND lines were normal, but they did not recycle hypoxanthine. These cells provide a novel resource to reveal insights into the relevance of heterogeneity among iPSC lines and applications for modeling LND.

Abstract

Three experiments tested young children's efficiency in recognizing words in speech referring to absent objects. Seventy-two 24-month-olds heard sentences containing target words denoting objects that were or were not present in a visual display. Children's eye movements were monitored as they heard the sentences. Three distinct patterns of response were shown. Children hearing a familiar word that was an appropriate label for the currently fixated picture maintained their gaze. Children hearing a familiar word that could not apply to the currently fixated picture rapidly shifted their gaze to the alternative picture, whether that alternative was the named target or not, and then continued to search for an appropriate referent. Finally, children hearing an unfamiliar word shifted their gaze slowly and irregularly. This set of outcomes is interpreted as evidence that by 24 months, rapid activation in word recognition does not depend on the presence of the words' referents. Rather, very young children are capable of quickly and efficiently interpreting words in the absence of visual supporting context.

Abstract

The degree to which infants represent phonetic detail in words has been a source of controversy in phonology and developmental psychology. One prominent hypothesis holds that infants store words in a vague or inaccurate form until the learning of similar–sounding neighbors forces attention to subtle phonetic distinctions. In the experiment reported here, we used a visual fixation task to assess word recognition. We present the first evidence indicating that, in fact, the lexical representations of 14– and 15–month–olds are encoded in fine detail, even when this detail is not functionally necessary for distinguishing similar words in the infant’s vocabulary. Exposure to words is sufficient for well–specified lexical representations, even well before the vocabulary spurt. These results suggest developmental continuity in infants’ representations of speech: As infants begin to build a vocabulary and learn word meanings, they use the perceptual abilities previously demonstrated in tasks testing the discrimination and categorization of meaningless syllables.

Abstract

When preparing to name an object, semantic knowledge about the object and its attributes is activated, including perceptual properties. It is unclear, however, whether semantic attribute activation contributes to lexical access or is a consequence of activating a concept irrespective of whether that concept is to be named or not. In this study, we measured neural responses using fMRI while participants named objects that are typically green or red, presented in black line drawings. Furthermore, participants underwent two other tasks with the same objects, color naming and semantic judgment, to see if the activation pattern we observe during picture naming is (a) similar to that of a task that requires accessing the color attribute and (b) distinct from that of a task that requires accessing the concept but not its name or color. We used representational similarity analysis to detect brain areas that show similar patterns within the same color category, but show different patterns across the two color categories. In all three tasks, activation in the bilateral fusiform gyri (“Human V4”) correlated with a representational model encoding the red–green distinction weighted by the importance of color feature for the different objects. This result suggests that when seeing objects whose color attribute is highly diagnostic, color knowledge about the objects is retrieved irrespective of whether the color or the object itself have to be named.

Abstract

This study explored sentence processing in two typologically distinct languages: Korean, a verb-final language, and Tongan, a verb-initial language. The first experiment revealed that in Korean, sentences arranged in the scrambled OSV (Object, Subject, Verb) order were processed more slowly than those in the canonical SOV order, highlighting a scrambling effect. It also found that sentences with subject topicalization in the SOV order were processed as swiftly as those in the canonical form, whereas sentences with object topicalization in the OSV order were processed with speeds and accuracy comparable to scrambled sentences. However, since topicalization and scrambling in Korean use the same OSV order, independently distinguishing the effects of topicalization is challenging. In contrast, Tongan allows for a clear separation of word orders for topicalization and scrambling, facilitating an independent evaluation of topicalization effects. The second experiment, employing a maze task, confirmed that Tongan’s canonical VSO order was processed more efficiently than the VOS scrambled order, thereby verifying a scrambling effect. The third experiment investigated the effects of both scrambling and topicalization in Tongan, finding that the canonical VSO order was processed most efficiently in terms of speed and accuracy, unlike the VOS scrambled and SVO topicalized orders. Notably, the OVS object-topicalized order was processed as efficiently as the VSO canonical order, while the SVO subject-topicalized order was slower than VSO but faster than VOS. By independently assessing the effects of topicalization apart from scrambling, this study demonstrates that both subject and object topicalization in Tongan facilitate sentence processing, contradicting the predictions based on movement-based anticipation.

Abstract

The murine homologue of the human chloride channel gene, CLCN5, defects in which are responsible for Dent disease, has been cloned and characterized. We isolated the entire coding region of mouse Clcn5 cDNA and approximately 45 kb of genomic sequence embracing the gene. To study its transcriptional control, the 5' upstream sequences of the mouse Clcn5 gene were cloned into a luciferase reporter vector. Deletion analysis of 1.5 kb of the 5' flanking sequence defined an active promoter region within 128 bp of the putative transcription start site, which is associated with a TATA motif but lacks a CAAT consensus. Within this sequence, there is a motif with homology to a purine-rich sequence responsible for the kidney-specific promoter activity of the rat CLC-K1 gene, another member of the chloride-channel gene family expressed in kidney. An enhancer element that confers a 10- to 20-fold increase in the promoter activity of the mouse Clcn5 gene was found within the first intron. The organization of the human CLCN5 and mouse Clcn5 gene structures is highly conserved, and the sequence of the murine protein is 98% similar to that of human, with its highest expression seen in the kidney. This study thus provides the first identification of the transcriptional control region of, and the basis for an understanding of the regulatory mechanism that controls, this kidney-specific, chloride-channel gene.

Abstract

First-language research suggests that new words, after initial episodic-memory encoding, are consolidated and hence become lexically integrated. We asked here if lexical consolidation, about word forms and meanings, occurs in a second language. Italian–English sequential bilinguals learned novel English-like words (e.g., apricon, taught to mean “stapler”). fMRI analyses failed to reveal a predicted shift, after consolidation time, from hippocampal to temporal neocortical activity. In a pause-detection task, responses to existing phonological competitors of learned words (e.g., apricot for apricon) were slowed down if the words had been learned two days earlier (i.e., after consolidation time) but not if they had been learned the same day. In a lexical-decision task, new words primed responses to semantically-related existing words (e.g., apricon-paper) whether the words were learned that day or two days earlier. Consolidation appears to support integration of words into the bilingual lexicon, possibly more rapidly for meanings than for forms.

Abstract

Neuronal oscillations putatively track speech in order to optimize sensory processing. However, it is unclear how isochronous brain oscillations can track pseudo-rhythmic speech input. Here we propose that oscillations can track pseudo-rhythmic speech when considering that speech time is dependent on content-based predictions flowing from internal language models. We show that temporal dynamics of speech are dependent on the predictability of words in a sentence. A computational model including oscillations, feedback, and inhibition is able to track pseudo-rhythmic speech input. As the model processes, it generates temporal phase codes, which are a candidate mechanism for carrying information forward in time. The model is optimally sensitive to the natural temporal speech dynamics and can explain empirical data on temporal speech illusions. Our results suggest that speech tracking does not have to rely only on the acoustics but could also exploit ongoing interactions between oscillations and constraints flowing from internal language models.

Abstract

Successful forgetting of unwanted memories is crucial for goal-directed behavior and mental wellbeing. While memory retention strengthens memory traces, it is unclear what happens to memory traces of events that are actively forgotten. Using intracranial EEG recordings from lateral temporal cortex, we find that memory traces for actively forgotten information are partially preserved and exhibit unique neural signatures. Memory traces of successfully remembered items show stronger encoding-retrieval similarity in gamma frequency patterns. By contrast, encoding-retrieval similarity of item-specific memory traces of actively forgotten items depend on activity at alpha/beta frequencies commonly associated with functional inhibition. Additional analyses revealed selective modification of item-specific patterns of connectivity and top-down information flow from dorsolateral prefrontal cortex to lateral temporal cortex in memory traces of intentionally forgotten items. These results suggest that intentional forgetting relies more on inhibitory top-down connections than intentional remembering, resulting in inhibitory memory traces with unique neural signatures and representational formats.

Abstract

From a brain's-eye-view, when a stimulus occurs and what it is are interrelated aspects of interpreting the perceptual world. Yet in practice, the putative perceptual inferences about sensory content and timing are often dichotomized and not investigated as an integrated process. We here argue that neural temporal dynamics can influence what is perceived, and in turn, stimulus content can influence the time at which perception is achieved. This computational principle results from the highly interdependent relationship of what and when in the environment. Both brain processes and perceptual events display strong temporal variability that is not always modeled; we argue that understanding—and, minimally, modeling—this temporal variability is key for theories of how the brain generates unified and consistent neural representations and that we ignore temporal variability in our analysis practice at the peril of both data interpretation and theory-building. Here, we review what and when interactions in the brain, demonstrate via simulations how temporal variability can result in misguided interpretations and conclusions, and outline how to integrate and synthesize what and when in theories and models of brain computation.

Abstract

Neural oscillations reflect fluctuations in excitability, which biases the percept of ambiguous sensory input. Why this bias occurs is still not fully understood. We hypothesized that neural populations representing likely events are more sensitive, and thereby become active on earlier oscillatory phases, when the ensemble itself is less excitable. Perception of ambiguous input presented during less-excitable phases should therefore be biased toward frequent or predictable stimuli that have lower activation thresholds. Here, we show such a frequency bias in spoken word recognition using psychophysics, magnetoencephalography (MEG), and computational modelling. With MEG, we found a double dissociation, where the phase of oscillations in the superior temporal gyrus and medial temporal gyrus biased word-identification behavior based on phoneme and lexical frequencies, respectively. This finding was reproduced in a computational model. These results demonstrate that oscillations provide a temporal ordering of neural activity based on the sensitivity of separable neural populations.

Abstract

This paper presents electrophysiological data on the on-line processing of open- and closed-class words in patients with Broca’s aphasia with agrammatic comprehension. Event-related brain potentials were recorded from the scalp when Broca patients and nonaphasic control subjects were visually presented with a story in which the words appeared one at a time on the screen. Separate waveforms were computed for open- and closed-class words. The non-aphasic control subjects showed clear differences between the processing of open- and closed-class words in an early (210-375 ms) and a late (400-700 ms) time-window.The early electrophysiological differences reflect the first manifestation of the availability of word-category information from the mental lexicon. The late differences presumably relate to post-lexical semantic and syntactic processing. In contrast to the control subjects, the Broca patients showed no early vocabulary class effect and only a limited late effect. The results suggest that an important factor in the agrammatic comprehension deficit of Broca’s aphasics is a delayed and/or incomplete availability of word-class information.

Abstract

This paper presents electrophysiological evidence of an impairment in the on-line processing of word class information in patients with Broca’s aphasia with agrammatic comprehension. Event-related brain potentials (ERPs) were recorded from the scalp while Broca patients and non-aphasic control subjects read open- and closed-class words that appeared one at a time on a PC screen. Separate waveforms were computed for open- and closed-class words. The non-aphasic control subjects showed a modulation of an early left anterior negativity in the 210–325 ms as a function of vocabulary class (VC), and a late left anterior negative shift to closed-class words in the 400–700 ms epoch. An N400 effect was present in both control subjects and Broca patients. We have taken the early electrophysiological differences to reflect the first availability of word-category information from the mental lexicon. The late differences can be related to post-lexical processing. In contrast to the control subjects, the Broca patients showed no early VC effect and no late anterior shift to closed-class words. The results support the view that an incomplete and/or delayed availability of word-class information might be an important factor in Broca’s agrammatic comprehension.

Abstract

During face-to-face conversation, transitions between speaker turns are incredibly fast. These fast turn exchanges seem to involve next speakers predicting upcoming semantic information, such that next turn planning can begin before a current turn is complete. Given that face-to-face conversation also involves the use of communicative bodily signals, an important question is how bodily signals such as co-speech hand gestures play into these processes of prediction and fast responding. In this corpus study, we found that hand gestures that depict or refer to semantic information started before the corresponding information in speech, which held both for the onset of the gesture as a whole, as well as the onset of the stroke (the most meaningful part of the gesture). This early timing potentially allows listeners to use the gestural information to predict the corresponding semantic information to be conveyed in speech. Moreover, we provided further evidence that questions with gestures got faster responses than questions without gestures. However, we found no evidence for the idea that how much a gesture precedes its lexical affiliate (i.e., its predictive potential) relates to how fast responses were given. The findings presented here highlight the importance of the temporal relation between speech and gesture and help to illuminate the potential mechanisms underpinning multimodal language processing during face-to-face conversation.

Abstract

Most language use occurs in face-to-face conversation, which involves rapid turn-taking. Seeing communicative bodily signals in addition to hearing speech may facilitate such fast responding. We tested whether this holds for co-speech hand gestures by investigating whether these gestures speed up button press responses to questions. Sixty native speakers of Dutch viewed videos in which an actress asked yes/no-questions, either with or without a corresponding iconic hand gesture. Participants answered the questions as quickly and accurately as possible via button press. Gestures did not impact response accuracy, but crucially, gestures sped up responses, suggesting that response planning may be finished earlier when gestures are seen. How much gestures sped up responses was not related to their timing in the question or their timing with respect to the corresponding information in speech. Overall, these results are in line with the idea that multimodality may facilitate fast responding during face-to-face conversation.

Abstract

The typical pattern of alternating turns in conversation seems trivial at first sight. But a closer look quickly reveals the cognitive challenges involved, with much of it resulting from the fast-paced nature of conversation. One core ingredient to turn coordination is the anticipation of upcoming turn ends so as to be able to ready oneself for providing the next contribution. Across two experiments, we investigated two variables inherent to face-to-face conversation, the presence of visual bodily signals and preceding discourse context, in terms of their contribution to turn end anticipation. In a reaction time paradigm, participants anticipated conversational turn ends better when seeing the speaker and their visual bodily signals than when they did not, especially so for longer turns. Likewise, participants were better able to anticipate turn ends when they had access to the preceding discourse context than when they did not, and especially so for longer turns. Critically, the two variables did not interact, showing that visual bodily signals retain their influence even in the context of preceding discourse. In a pre-registered follow-up experiment, we manipulated the visibility of the speaker's head, eyes and upper body (i.e. torso + arms). Participants were better able to anticipate turn ends when the speaker's upper body was visible, suggesting a role for manual gestures in turn end anticipation. Together, these findings show that seeing the speaker during conversation may critically facilitate turn coordination in interaction.

Abstract

Words are not processed in isolation; instead, they are commonly embedded in phrases and sentences. The sentential context influences the perception and processing of a word. However, how this is achieved by brain processes and whether predictive mechanisms underlie this process remain a debated topic. Here, we employed an experimental paradigm in which we orthogonalized sentence context constraints and predictive validity, which was defined as the ratio of congruent to incongruent sentence endings within the experiment. While recording electroencephalography, participants read sentences with three levels of sentential context constraints (high, medium, and low). Participants were also separated into two groups that differed in their ratio of valid congruent to incongruent target words that could be predicted from the sentential context. For both groups, we investigated modulations of alpha power before, and N400 amplitude modulations after target word onset. The results reveal that the N400 amplitude gradually decreased with higher context constraints and cloze probability. In contrast, alpha power was not significantly affected by context constraint. Neither the N400 nor alpha power were significantly affected by changes in predictive validity.

Abstract

The existence of nominal classification systems has long been thought of as one of the defining features of the Papuan languages of island New Guinea. However, while almost all of these languages do have nominal classification systems, they are, in fact, extremely divergent from each other. This paper examines these systems in the East Papuan languages in order to examine the question of the relationship between these Papuan outliers. Nominal classification systems are often archaic, preserving older features lost elsewhere in a language. Also, evidence shows that they are not easily borrowed into languages (although they can be). For these reasons, it is useful to consider nominal classification systems as a tool for exploring ancient historical relationships between languages. This paper finds little evidence of relationship between the nominal classification systems of the East Papuan languages as a whole. It argues that the mere existence of nominal classification systems cannot be used as evidence that the East Papuan languages form a genetic family. The simplest hypothesis is that either the systems were inherited so long ago as to obscure the genetic evidence, or else the appearance of nominal classification systems in these languages arose through borrowing of grammatical systems rather than of morphological forms.

Abstract

This paper explores the issue of documenting an endangered language from the perspective of a community with low levels of literacy, I first discuss the background of the language community with whom I work, the Lavukal people of Solomon Islands, and discuss whether, and to what extent, Lavukaleve is an endangered language. I then go on to discuss the documentation project. My main point is that while low literacy levels and a nonreading culture would seem to make documentation a strange choice as a tool for language maintenance, in fact both serve as powerful cultural symbols of the importance and prestige of Lavukaleve. It is well known that a common reason for language death is that speakers choose not to transmit their language to the next generation (e.g. Winter 1993). Lavukaleve is particularly vulnerable in this respect. By utilizing cultural symbols of status and prestige, the standing of Lavukaleve can be enhanced, thus helping to ensure the transmission of Lavukaleve to future generations.

Abstract

This study investigated different accounts of early argument structure acquisition and verb paradigm building through the detailed examination of the acquisition of the verb Go. Data from 11 children followed longitudinally between the ages of 2;0 and 3;0 were examined. Children's uses of the different forms of Go were compared with respect to syntactic structure and the semantics encoded. The data are compatible with the suggestion that the children were not operating with a single verb representation that differentiated between different forms of Go but rather that their knowledge of the relationship between the different forms of Go varied depending on the structure produced and the meaning encoded. However, a good predictor of the children's use of different forms of Go in particular structures and to express particular meanings was the frequency of use of those structures and meanings with particular forms of Go in the input. The implications of these findings for theories of syntactic category formation and abstract rule-based descriptions of grammar are discussed.

Abstract

In many areas of language acquisition, researchers have suggested that semantic generality plays an important role in determining the order of acquisition of particular lexical forms. However, generality is typically confounded with the effects of input frequency and it is therefore unclear to what extent semantic generality or input frequency determines the early acquisition of particular lexical items. The present study evaluates the relative influence of semantic status and properties of the input on the acquisition of verbs and their argument structures in the early speech of 9 English-speaking children from 2;0 to 3;0. The children's early verb utterances are examined with respect to (1) the order of acquisition of particular verbs in three different constructions, (2) the syntactic diversity of use of individual verbs, (3) the relative proportional use of semantically general verbs as a function of total verb use, and (4) their grammatical accuracy. The data suggest that although measures of semantic generality correlate with various measures of early verb use, once the effects of verb use in the input are removed, semantic generality is not a significant predictor of early verb use. The implications of these results for semantic-based theories of verb argument structure acquisition are discussed.

Abstract

Sentence comprehension is highly practiced and largely automatic, but this belies the complexity of the underlying processes. We used functional neuroimaging to investigate garden-path sentences that cause difficulty during comprehension, in order to unpack the different processes used to support sentence interpretation. By investigating garden-path and other types of sentences within the same individuals, we functionally profiled different regions within the temporal and frontal cortices in the left hemisphere. The results revealed that different aspects of comprehension difficulty are handled by left posterior temporal, left anterior temporal, ventral left frontal, and dorsal left frontal cortices. The functional profiles of these regions likely lie along a spectrum of specificity to generality, including language-specific processing of linguistic representations, more general conflict resolution processes operating over linguistic representations, and processes for handling difficulty in general. These findings suggest that difficulty is not unitary and that there is a role for a variety of linguistic and non-linguistic processes in supporting comprehension.

Abstract

Written language comprehension requires readers to integrate incoming information with stored mental knowledge to construct meaning. Literally plausible idiomatic expressions can activate both figurative and literal interpretations, which convey different meanings. Previous research has shown that contexts biasing the figurative or literal interpretation of an idiom can facilitate its processing. Moreover, there is evidence that processing of idiomatic expressions is subject to individual differences in linguistic knowledge and cognitive-linguistic skills. It is therefore conceivable that individuals vary in the extent to which they experience context-induced facilitation in processing idiomatic expressions. To explore the interplay between reader-related variables and contextual facilitation, we conducted a self-paced reading experiment. We recruited participants who had recently completed a battery of 33 behavioural tests measuring individual differences in linguistic knowledge, general cognitive skills and linguistic processing skills. In the present experiment, a subset of these participants read idiomatic expressions that were either presented in isolation or preceded by a figuratively or literally biasing context. We conducted analyses on the reading times of idiom-final nouns and the word thereafter (spill-over region) across the three conditions, including participants’ scores from the individual differences battery. Our results showed no main effect of the preceding context, but substantial variation in contextual facilitation between readers. We observed main effects of participants’ word reading ability and non-verbal intelligence on reading times as well as an interaction between condition and linguistic knowledge. We encourage interested researchers to exploit the present dataset for follow-up studies on individual differences in idiom processing.

Abstract

Structural brain changes along the lineage leading to modern Homo sapiens contributed to our distinctive cognitive and social abilities. However, the evolutionarily relevant molecular variants impacting key aspects of neuroanatomy are largely unknown. Here, we integrate evolutionary annotations of the genome at diverse timescales with common variant associations from large-scale neuroimaging genetic screens. We find that alleles with evidence of recent positive polygenic selection over the past 2000–3000 years are associated with increased surface area (SA) of the entire cortex, as well as specific regions, including those involved in spoken language and visual processing. Therefore, polygenic selective pressures impact the structure of specific cortical areas even over relatively recent timescales. Moreover, common sequence variation within human gained enhancers active in the prenatal cortex is associated with postnatal global SA. We show that such variation modulates the function of a regulatory element of the developmentally relevant transcription factor HEY2 in human neural progenitor cells and is associated with structural changes in the inferior frontal cortex. These results indicate that non-coding genomic regions active during prenatal cortical development are involved in the evolution of human brain structure and identify novel regulatory elements and genes impacting modern human brain structure.

Abstract

Bilinguals possess the ability of expressing themselves in more than one language, and typically do so in contextually rich and dynamic settings. Theories and models have indeed long considered context factors to affect bilingual language production in many ways. However, most experimental studies in this domain have failed to fully incorporate linguistic, social, or physical context aspects, let alone combine them in the same study. Indeed, most experimental psycholinguistic research has taken place in isolated and constrained lab settings with carefully selected words or sentences, rather than under rich and naturalistic conditions. We argue that the most influential experimental paradigms in the psycholinguistic study of bilingual language production fall short of capturing the effects of context on language processing and control presupposed by prominent models. This paper therefore aims to enrich the methodological basis for investigating context aspects in current experimental paradigms and thereby move the field of bilingual language production research forward theoretically. After considering extensions of existing paradigms proposed to address context effects, we present three far-ranging innovative proposals, focusing on virtual reality, dialog situations, and multimodality in the context of bilingual language production.

Abstract

Vocal plasticity can occur in response to environmental and biological factors, including conspecifics' vocalizations and noise. Pinnipeds are one of the few mammalian groups capable of vocal learning, and are therefore relevant to understanding the evolution of vocal plasticity in humans and other animals. Here, we investigate the vocal plasticity of harbour seals (Phoca vitulina), a species with vocal learning abilities observed in adulthood but not puppyhood. To evaluate early mammalian vocal development, we tested 1–3 weeks-old seal pups. We tailored noise playbacks to this species and age to induce seal pups to shift their fundamental frequency (f0), rather than adapt call amplitude or temporal characteristics. We exposed individual pups to low- and high-intensity bandpass-filtered noise, which spanned—and masked—their typical range of f0; simultaneously, we recorded pups' spontaneous calls. Unlike most mammals, pups modified their vocalizations by lowering their f0 in response to increased noise. This modulation was precise and adapted to the particular experimental manipulation of the noise condition. In addition, higher levels of noise induced less dispersion around the mean f0, suggesting that pups may have actively focused their phonatory efforts to target lower frequencies. Noise did not seem to affect call amplitude. However, one seal showed two characteristics of the Lombard effect known for human speech in noise: significant increase in call amplitude and flattening of spectral tilt. Our relatively low noise levels may have favoured f0 modulation while inhibiting amplitude adjustments. This lowering of f0 is unusual, as most animals commonly display no such f0 shift. Our data represent a relatively rare case in mammalian neonates, and have implications for the evolution of vocal plasticity and vocal learning across species, including humans.

Abstract

In referential communication, Grice's Maxim of Quantity is thought to imply that utterances conveying unnecessary information should incur comprehension difficulties. There is, however, considerable evidence that speakers frequently encode redundant information in their referring expressions, raising the question as to whether such overspecifications hinder listeners' processing. Evidence from previous work is inconclusive, and mostly comes from offline studies. In this article, we present two event-related potential (ERP) experiments, investigating the real-time comprehension of referring expressions that contain redundant adjectives in complex visual contexts. Our findings provide support for both Gricean and bounded-rational accounts. We argue that these seemingly incompatible results can be reconciled if common ground is taken into account. We propose a bounded-rational account of overspecification, according to which even redundant words can be beneficial to comprehension to the extent that they facilitate the reduction of listeners' uncertainty regarding the target referent.

Abstract

Animacy, commonly defined as the distinction between living and non-living entities, is a useful notion in cognitive science and linguistics employed to describe and predict variation in psychological and linguistic behaviour. In the (psycho)linguistics literature we find linguistic animacy dichotomies which are (implicitly) assumed to correspond to biological dichotomies. We argue this is problematic, as it leaves us without a cognitively grounded, universal description for non-prototypical cases. We show that ‘animacy’ in language can be better understood as universally emerging from a gradual, cognitive property by collecting animacy ratings for a great range of nouns from Japanese and Persian. We used these cognitive ratings in turn to predict linguistic variation in these languages traditionally explained through dichotomous distinctions. We show that whilst (speakers of) languages may subtly differ in their conceptualisation of animacy, universality may be found in the process of mapping conceptual animacy to linguistic variation.

Abstract

During natural conversation, people must quickly understand the meaning of what the other speaker is saying. This concerns not just the semantic content of an utterance, but also the social action (i.e., what the utterance is doing—requesting information, offering, evaluating, checking mutual understanding, etc.) that the utterance is performing. The multimodal nature of human language raises the question of whether visual signals may contribute to the rapid processing of such social actions. However, while previous research has shown that how we move reveals the intentions underlying instrumental actions, we do not know whether the intentions underlying fine-grained social actions in conversation are also revealed in our bodily movements. Using a corpus of dyadic conversations combined with manual annotation and motion tracking, we analyzed the kinematics of the torso, head, and hands during the asking of questions. Manual annotation categorized these questions into six more fine-grained social action types (i.e., request for information, other-initiated repair, understanding check, stance or sentiment, self-directed, active participation). We demonstrate, for the first time, that the kinematics of the torso, head and hands differ between some of these different social action categories based on a 900 ms time window that captures movements starting slightly prior to or within 600 ms after utterance onset. These results provide novel insights into the extent to which our intentions shape the way that we move, and provide new avenues for understanding how this phenomenon may facilitate the fast communication of meaning in conversational interaction, social action, and conversation

Abstract

In everyday conversation, we are often challenged with communicating in non-ideal settings, such as in noise. Increased speech intensity and larger mouth movements are used to overcome noise in constrained settings (the Lombard effect). How we adapt to noise in face-to-face interaction, the natural environment of human language use, where manual gestures are ubiquitous, is currently unknown. We asked Dutch adults to wear headphones with varying levels of multi-talker babble while attempting to communicate action verbs to one another. Using quantitative motion capture and acoustic analyses, we found that (1) noise is associated with increased speech intensity and enhanced gesture kinematics and mouth movements, and (2) acoustic modulation only occurs when gestures are not present, while kinematic modulation occurs regardless of co-occurring speech. Thus, in face-to-face encounters the Lombard effect is not constrained to speech but is a multimodal phenomenon where the visual channel carries most of the communicative burden.

Abstract

In human communication, social intentions and meaning are often revealed in the way we move. In this study, we investigate the flexibility of human communication in terms of kinematic modulation in a clinical population, namely, autistic individuals. The aim of this study was twofold: to assess (a) whether communicatively relevant kinematic features of gestures differ between autistic and neurotypical individuals, and (b) if autistic individuals use communicative kinematic modulation to support gesture recognition. We tested autistic and neurotypical individuals on a silent gesture production task and a gesture comprehension task. We measured movement during the gesture production task using a Kinect motion tracking device in order to determine if autistic individuals differed from neurotypical individuals in their gesture kinematics. For the gesture comprehension task, we assessed whether autistic individuals used communicatively relevant kinematic cues to support recognition. This was done by using stick-light figures as stimuli and testing for a correlation between the kinematics of these videos and recognition performance. We found that (a) silent gestures produced by autistic and neurotypical individuals differ in communicatively relevant kinematic features, such as the number of meaningful holds between movements, and (b) while autistic individuals are overall unimpaired at recognizing gestures, they processed repetition and complexity, measured as the amount of submovements perceived, differently than neurotypicals do. These findings highlight how subtle aspects of neurotypical behavior can be experienced differently by autistic individuals. They further demonstrate the relationship between movement kinematics and social interaction in high-functioning autistic individuals.

Abstract

Human language is extremely versatile, combining a limited set of signals in an unlimited number of ways. However, it is unknown whether conversational visual signals feed into the composite utterances with which speakers communicate their intentions. We assessed whether different combinations of visual signals lead to different intent interpretations of the same spoken utterance. Participants viewed a virtual avatar uttering spoken questions while producing single visual signals (i.e., head turn, head tilt, eyebrow raise) or combinations of these signals. After each video, participants classified the communicative intention behind the question. We found that composite utterances combining several visual signals conveyed different meaning compared to utterances accompanied by the single visual signals. However, responses to combinations of signals were more similar to the responses to related, rather than unrelated, individual signals, indicating a consistent influence of the individual visual signals on the whole. This study therefore provides first evidence for compositional, non-additive (i.e., Gestalt-like) perception of multimodal language.

Abstract

The natural ecology of language is conversation, with individuals taking turns speaking to communicate in a back-and-forth fashion. Language in this context involves strings of words that a listener must process while simultaneously planning their own next utterance. It would thus be highly advantageous if language users distributed information within an utterance in a way that may facilitate this processing–planning dynamic. While some studies have investigated how information is distributed at the level of single words or clauses, or in written language, little is known about how information is distributed within spoken utterances produced during naturalistic conversation. It also is not known how information distribution patterns of spoken utterances may differ across languages. We used a set of matched corpora (CallHome) containing 898 telephone conversations conducted in six different languages (Arabic, English, German, Japanese, Mandarin, and Spanish), analyzing more than 58,000 utterances, to assess whether there is evidence of distinct patterns of information distributions at the utterance level, and whether these patterns are similar or differed across the languages. We found that English, Spanish, and Mandarin typically show a back-loaded distribution, with higher information (i.e., surprisal) in the last half of utterances compared with the first half, while Arabic, German, and Japanese showed front-loaded distributions, with higher information in the first half compared with the last half. Additional analyses suggest that these patterns may be related to word order and rate of noun and verb usage. We additionally found that back-loaded languages have longer turn transition times (i.e.,time between speaker turns)

Abstract

Spanish–English bilinguals rarely code-switch in the perfect structure between the Spanish auxiliary haber (“to have”) and the participle (e.g., “Ella ha voted”; “She has voted”). However, they are somewhat likely to switch in the progressive structure between the Spanish auxiliary estar (“to be”) and the participle (“Ella está voting”; “She is voting”). This phenomenon is known as the “auxiliary phrase asymmetry”. One hypothesis as to why this occurs is that estar has more semantic weight as it also functions as an independent verb, whereas haber is almost exclusively used as an auxiliary verb. To test this hypothesis, we employed a connectionist model that produces spontaneous code-switches. Through simulation experiments, we showed that i) the asymmetry emerges in the model and that ii) the asymmetry disappears when using haber also as a main verb, which adds semantic weight. Therefore, the lack of semantic weight of haber may indeed cause the asymmetry.

Abstract

Code-switching is the alternation from one language to the other during bilingual speech. We present a novel method of researching this phenomenon using computational cognitive modeling. We trained a neural network of bilingual sentence production to simulate early balanced Spanish–English bilinguals, late speakers of English who have Spanish as a dominant native language, and late speakers of Spanish who have English as a dominant native language. The model produced code-switches even though it was not exposed to code-switched input. The simulations predicted how code-switching patterns differ between early balanced and late non-balanced bilinguals; the balanced bilingual simulation code-switches considerably more frequently, which is in line with what has been observed in human speech production. Additionally, we compared the patterns produced by the simulations with two corpora of spontaneous bilingual speech and identified noticeable commonalities and differences. To our knowledge, this is the first computational cognitive model simulating the code-switched production of non-balanced bilinguals and comparing the simulated production of balanced and non-balanced bilinguals with that of human bilinguals.

Abstract

Although language depends on storage and composition, just what is stored or (de)composed remains unclear. We leveraged working memory load limitations to test for composition, hypothesizing that decomposed forms should particularly tax working memory. We focused on a well-studied paradigm, English inflectional morphology. We predicted that (compositional) regulars should be harder to maintain in working memory than (non-compositional) irregulars, using a 3-back production task. Frequency, phonology, orthography, and other potentially confounding factors were controlled for. Compared to irregulars, regulars and their accompanying −s/−ing-affixed filler items yielded more errors. Underscoring the decomposition of only regulars, regulars yielded more bare-stem (e.g., walk) and stem affixation errors (walks/walking) than irregulars, whereas irregulars yielded more past-tense-form affixation errors (broughts/tolded). In line with previous evidence that regulars can be stored under certain conditions, the regular-irregular difference held specifically for phonologically consistent (not inconsistent) regulars, in particular for both low and high frequency consistent regulars in males, but only for low frequency consistent regulars in females. Sensitivity analyses suggested the findings were robust. The study further elucidates the computation of inflected forms, and introduces a simple diagnostic for linguistic composition.

Abstract

A considerable amount of the population in more economically developed countries are functionally illiterate (i.e., low literate). Despite some years of schooling and basic reading skills, these individuals cannot properly read and write and, as a consequence have problems to understand even short texts. An often-discussed approach (Greenberg et al., 1997) assumes weak phonological processing skills coupled with untreated developmental dyslexia as possible causes of functional illiteracy. Although there is some data suggesting commonalities between low literacy and developmental dyslexia, it is still not clear, whether these reflect shared consequences (i.e., cognitive and behavioral profile) or shared causes. The present systematic review aims at exploring the similarities and differences identified in empirical studies investigating both functional illiterate and developmental dyslexic samples. Nine electronic databases were searched in order to identify all quantitative studies published in English or German. Although a broad search strategy and few limitations were applied, only 5 studies have been identified adequate from the resulting 9269 references. The results point to the lack of studies directly comparing functional illiterate with developmental dyslexic samples. Moreover, a huge variance has been identified between the studies in how they approached the concept of functional illiteracy, particularly when it came to critical categories such the applied definition, terminology, criteria for inclusion in the sample, research focus, and outcome measures. The available data highlight the need for more direct comparisons in order to understand what extent functional illiteracy and dyslexia share common characteristics.

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

In this article we investigate how speakers manage discourse expectations in dialogue by comparing the meaning and use of three Dutch discourse particles, i.e. wel, toch and eigenlijk, which all express a contrast between their host utterance and a discourse-based expectation. The core meanings of toch, wel and eigenlijk are formally distinguished on the basis of two intersubjective parameters: (i) whether the particle marks alignment or misalignment between speaker and addressee discourse beliefs, and (ii) whether the particle requires an assessment of the addressee’s representation of mutual discourse beliefs. By means of a quantitative corpus study, we investigate to what extent the intersubjective meaning distinctions between wel, toch and eigenlijk are reflected in statistical usage patterns across different social situations. Results suggest that wel, toch and eigenlijk are lexicalizations of distinct generalized politeness strategies when expressing contrast in social interaction. Our findings call for an interdisciplinary approach to discourse particles in order to enhance our understanding of their functions in language.

Abstract

Controlling aggression is a crucial skill in social species like rodents and humans and has been associated with anterior cingulate cortex (ACC). Here, we directly link the failed regulation of aggression in BALB/cJ mice to ACC hypofunction. We first show that ACC in BALB/cJ mice is structurally degraded: neuron density is decreased, with pervasive neuron death and reactive astroglia. Gene-set enrichment analysis suggested that this process is driven by neuronal degeneration, which then triggers toxic astrogliosis. cFos expression across ACC indicated functional consequences: during aggressive encounters, ACC was engaged in control mice, but not BALB/cJ mice. Chemogenetically activating ACC during aggressive encounters drastically suppressed pathological aggression but left species-typical aggression intact. The network effects of our chemogenetic perturbation suggest that this behavioral rescue is mediated by suppression of amygdala and hypothalamus and activation of mediodorsal thalamus. Together, these findings highlight the central role of ACC in curbing pathological aggression.

Abstract

The language system uses syntactic, semantic, as well as prosodic cues to efficiently guide auditory sentence comprehension. Prosodic cues, such as pitch accents, can build expectations about upcoming sentence elements. This study investigates to what extent syntactic and semantic expectations generated by pitch accents can be dissociated and if so, which cues take precedence when contradictory information is present. We used sentences in which one out of two nominal constituents was placed in contrastive focus with a third one. All noun phrases carried overt syntactic information (case-marking of the determiner) and semantic information (typicality of the thematic role of the noun). Two experiments (a sentence comprehension and a sentence completion task) show that focus, marked by pitch accents, established expectations in both syntactic and semantic domains. However, only the syntactic expectations, when violated, were strong enough to interfere with sentence comprehension. Furthermore, when contradictory cues occurred in the same sentence, the local syntactic cue (case-marking) took precedence over the semantic cue (thematic role), and overwrote previous information cued by prosody. The findings indicate that during auditory sentence comprehension the processing system integrates different sources of information for argument role assignment, yet primarily relies on syntactic information.

Abstract

Written language, a human cultural invention, is far too recent for dedicated neural
infrastructure to have evolved in its service. Culturally newly acquired skills (e.g. reading) thus ‘recycle’ evolutionarily older circuits that originally evolved for different, but similar functions (e.g. visual object recognition). The destructive competition hypothesis predicts that this neuronal recycling has detrimental behavioral effects on the cognitive functions a cortical network originally evolved for. In a study with 97 literate, low-literate, and illiterate participants from the same socioeconomic background we find that even after adjusting for cognitive ability and test-taking familiarity, learning to read is associated with an increase, rather than a decrease, in object recognition abilities. These results are incompatible with the claim that neuronal recycling results in destructive competition and consistent with the possibility that learning to read instead fine-tunes general object recognition mechanisms, a hypothesis that needs further neuroscientific investigation.

Abstract

In this paper we investigate acoustic differences between vowels in syllables that do or do not carry lexical stress. In doing so, we concentrated on segmental acoustic phonetic features that are conventionally assumed to differ between stressed and unstressed syllables, viz. Duration, Energy and Spectral Tilt. The speech material in this study differs from the type of material used in previous research: instead of specially constructed sentences we used phonetically rich sentences from the Dutch POLYPHONE corpus. Most of the Duration, Energy and Spectral Tilt features that we used in the investigation show statistically significant differences for the population means of stressed and unstressed vowels. However, it also appears that the distributions overlap to such an extent that automatic detection of stressed and unstressed syllables yields correct classifications of 72.6% at best. It is argued that this result is due to the large variety in the ways in which the abstract linguistic feature `lexical stress' is realized in the acoustic speech signal. Our findings suggest that a lexical stress detector has little use for a single pass decoder in an automatic speech recognition (ASR) system, but could still play a useful role as an additional knowledge source in a multi-pass decoder.

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

An event-related brain potentials experiment was carried out to examine the interplay of referential and structural factors during sentence processing in discourse. Subjects read (Dutch) sentences beginning like “David told the girl that … ” in short story contexts that had introduced either one or two referents for a critical singular noun phrase (“the girl”). The waveforms showed that within 280 ms after onset of the critical noun the reader had already determined whether the noun phrase had a unique referent in earlier discourse. Furthermore, this referential information was immediately used in parsing the rest of the sentence, which was briefly ambiguous between a complement clause (“ … that there would be some visitors”) and a relative clause (“ … that had been on the phone to hang up”). A consistent pattern of P600/SPS effects elicited by various subsequent disambiguations revealed that a two-referent discourse context had led the parser to initially pursue the relative-clause alternative to a larger extent than a one-referent context. Together, the results suggest that during the processing of sentences in discourse, structural and referential sources of information interact on a word-by-word basis.

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

We report a series of experiments examining the effects on word processing of insertion of an optional epenthetic vowel in word-final consonant clusters in Dutch. Such epenthesis turns film, for instance, into film. In a word-reversal task listeners treated words with and without epenthesis alike, as monosyllables, suggesting that the variant forms both activate the same canonical representation, that of a monosyllabic word without epenthesis. In both lexical decision and word spotting, response times to recognize words were significantly faster when epenthesis was present than when the word was presented in its canonical form without epenthesis. It is argued that addition of the epenthetic vowel makes the liquid consonants constituting the first member of a cluster more perceptible; a final phoneme-detection experiment confirmed that this was the case. These findings show that a transformed variant of a word, although it contacts the lexicon via the representation of the canonical form, can be more easily perceptible than that canonical form.

Abstract

This paper addresses the question of whether noun incorporation is a syntactically base-generated or a syntactically derived construction. Focusing on so-called 'raised possessors' in West Greenlandic noun incorporating constructions and presenting some new data, I discuss some problems that arise if we use the derivational framework of Bittner and Hale (1996) to analyze them. I show that if we make the predication relations in noun incorporating constructions overt in their syntax and if we adopt a dynamic approach to semantics, a base-generated syntactic input enriched with a coindexation system is all that we need to arrive at an adequate semantic interpretation of these constructions.

Abstract

Autism Spectrum Disorder (ASD) is often associated with impaired perspective-taking skills. Deception is an important indicator of perspective-taking, and therefore may be thought to pose difficulties to people with ASD (e.g., Baron-Cohen in J Child Psychol Psychiatry 3:1141–1155, 1992). To test this hypothesis, we asked participants with and without ASD to play a computerised deception game. We found that participants with ASD were equally likely—and in complex cases of deception even more likely—to deceive and detect deception, and learned deception at a faster rate. However, participants with ASD initially deceived less frequently, and were slower at detecting deception. These results suggest that people with ASD readily engage in deception but may do so through conscious and effortful reasoning about other people’s perspectiv

Abstract

This paper introduces a novel collection of word embeddings, numerical representations of lexical semantics, in 55 languages, trained on a large corpus of pseudo-conversational speech transcriptions from television shows and movies. The embeddings were trained on the OpenSubtitles corpus using the fastText implementation of the skipgram algorithm. Performance comparable with (and in some cases exceeding) embeddings trained on non-conversational (Wikipedia) text is reported on standard benchmark evaluation datasets. A novel evaluation method of particular relevance to psycholinguists is also introduced: prediction of experimental lexical norms in multiple languages. The models, as well as code for reproducing the models and all analyses reported in this paper (implemented as a user-friendly Python package), are freely available at: https://github.com/jvparidon/subs2vec.

Abstract

In two ERP experiments we investigated how and when the language comprehension system relates an incoming word to semantic representations of an unfolding local sentence and a wider discourse. In experiment 1, subjects were presented with short stories. The last sentence of these stories occasionally contained a critical word that, although acceptable in the local sentence context, was semantically anomalous with respect to the wider discourse (e.g., "Jane told the brother that he was exceptionally slow" in a discourse context where he had in fact been very quick). Relative to coherent control words (e.g., "quick"), these discourse-dependent semantic anomalies elicited a large N400 effect that began at about 200-250 ms after word onset. In experiment 2, the same sentences were presented without their original story context. Although the words that had previously been anomalous in discourse still elicited a slightly larger average N400 than the coherent words, the resulting N400 effect was much reduced, showing that the large effect observed in stories was related to the wider discourse. In the same experiment, single sentences that contained a clear local semantic anomaly elicited a standard sentence-dependent N400 effect (e.g., Kutas & Hillyard, 1980). The N400 effects elicited in discourse and in single sentences had the same time course, overall morphology, and scalp distribution. We argue that these findings are most compatible with models of language processing in which there is no fundamental distinction between the integration of a word in its local (sentence-level) and its global (discourse-level) semantic context.

Abstract

We review the implications of recent ERP evidence for when and how grammatical gender agreement constrains sentence parsing. In some theories of parsing, gender is assumed to immediately and categorically block gender-incongruent phrase structure alternatives from being pursued. In other theories, the parser initially ignores gender altogether. The ERP evidence we discuss suggests an intermediate position, in which grammatical gender does not immediately block gender-incongruent phrase structures from being considered, but is used to dispose of them shortly thereafter.

Abstract

Motor-related brain potentials were used to examine the time course of grammatical and phonological processes during noun phrase production in Dutch. In the experiments, participants named colored pictures using a no-determiner noun phrase. On half of the trials a syntactic-phonological classification task had to be performed before naming. Depending on the outcome of the classifications, a left or a right push-button response was given (go trials), or no push-button response was given (no-go trials). Lateralized readiness potentials (LRPs) were derived to test whether syntactic and phonological information affected the motor system at separate moments in time. The results showed that when syntactic information determined the response-hand decision, an LRP developed on no-go trials. However, no such effect was observed when phonological information determined response hand. On the basis of the data, it can be estimated that an additional period of at least 40 ms is needed to retrieve a word's initial phoneme once its lemma has been retrieved. These results provide evidence for the view that during speaking, grammatical processing precedes phonological processing in time.

Abstract

Do aesthetic preferences for images of neatly organized compositions (e.g., images collected on blogs like Things Organized Neatly©) generalize across cultures? In an earlier study, focusing on stimulus and personal properties related to order and complexity, Western participants indicated their preference for one of two simultaneously presented images (100 pairs). In the current study, we compared the data of the native Dutch-speaking participants from this earlier sample (N = 356) to newly collected data from a native Chinese-speaking sample (N = 220). Overall, aesthetic preferences were quite similar across cultures. When relating preferences for each sample to ratings of order, complexity, soothingness, and fascination collected from a Western, mainly Dutch-speaking sample, the results hint at a cross-culturally consistent preference for images that Western participants rate as more ordered, but a cross-culturally diverse relation between preferences and complexity.

Abstract

thebeat is a Python package for working with temporal sequences and rhythms in the behavioral and cognitive sciences, as well as in bioacoustics. It provides functionality for creating experimental stimuli, and for visualizing and analyzing temporal data. Sequences, sounds, and experimental trials can be generated using single lines of code. thebeat contains functions for calculating common rhythmic measures, such as interval ratios, and for producing plots, such as circular histograms. thebeat saves researchers time when creating experiments, and provides the first steps in collecting widely accepted methods for use in timing research. thebeat is an open-source, on-going, and collaborative project, and can be extended for use in specialized subfields. thebeat integrates easily with the existing Python ecosystem, allowing one to combine our tested code with custom-made scripts. The package was specifically designed to be useful for both skilled and novice programmers. thebeat provides a foundation for working with temporal sequences onto which additional functionality can be built. This combination of specificity and plasticity should facilitate research in multiple research contexts and fields of study.

Abstract

* - indicates joint first authorship -
The ability to discriminate between familiar and unfamiliar calls may play a key role in pinnipeds’ communication and survival, as in the case of mother-pup interactions. Vocal discrimination abilities have been suggested to be more developed in pinniped species with the highest selective pressure such as the otariids; yet, in some group-living phocids, such as harbor seals (Phoca vitulina), mothers are also able to recognize their pup’s voice. Conspecifics’ vocal recognition in pups has never been investigated; however, the repeated interaction occurring between pups within the breeding season suggests that long-term vocal discrimination may occur. Here we explored this hypothesis by presenting three rehabilitated seal pups with playbacks of vocalizations from unfamiliar or familiar pups. It is uncommon for seals to come into rehabilitation for a second time in their lifespan, and this study took advantage of these rare cases. A simple visual inspection of the data plots seemed to show more reactions, and of longer duration, in response to familiar as compared to unfamiliar playbacks in two out of three pups. However, statistical analyses revealed no significant difference between the experimental conditions. We also found no significant asymmetry in orientation (left vs. right) towards familiar and unfamiliar sounds. While statistics do not support the hypothesis of an established ability to discriminate familiar vocalizations from unfamiliar ones in harbor seal pups, further investigations with a larger sample size are needed to confirm or refute this hypothesis.

Abstract

In two ERP experiments, we investigated whether readers prioritize animacy over real-world event-knowledge during sentence comprehension. We used the paradigm of Paczynski and Kuperberg (2012), who argued that animacy is prioritized based on the observations that the ‘related anomaly effect’ (reduced N400s for context-related anomalous words compared to unrelated words) does not occur for animacy violations, and that animacy violations but not relatedness violations elicit P600 effects. Participants read passive sentences with plausible agents (e.g., The prescription for the mental disorder was written by the psychiatrist) or implausible agents that varied in animacy and semantic relatedness (schizophrenic/guard/pill/fence). In Experiment 1 (with a plausibility judgment task), plausible sentences elicited smaller N400s relative to all types of implausible sentences. Crucially, animate words elicited smaller N400s than inanimate words, and related words elicited smaller N400s than unrelated words, but Bayesian analysis revealed substantial evidence against an interaction between animacy and relatedness. Moreover, at the P600 time-window, we observed more positive ERPs for animate than inanimate words and for related than unrelated words at anterior regions. In Experiment 2 (without judgment task), we observed an N400 effect with animacy violations, but no other effects. Taken together, the results of our experiments fail to support a prioritized role of animacy information over real-world event-knowledge, but they support an interactive, constraint-based view on incremental semantic processing.

Abstract

We investigated the “proximate unit” in Korean, that is, the initial phonological unit selected in speech production by Korean speakers. Previous studies have shown mixed evidence indicating either a phoneme-sized or a syllable-sized unit. We conducted two experiments in which participants named pictures while ignoring superimposed non-words. In English, for this task, when the picture (e.g., dog) and distractor phonology (e.g., dark) initially overlap, typically the picture target is named faster. We used a range of conditions (in Korean) varying from onset overlap to syllabic overlap, and the results indicated an important role for the syllable, but not the phoneme. We suggest that the basic unit used in phonological encoding in Korean is different from Germanic languages such as English and Dutch and also from Japanese and possibly also Chinese. Models dealing with the architecture of language production can use these results when providing a framework suitable for all languages in the world, including Korean.

Abstract

There is evidence from both behavior and brain activity that the way information is structured, through the use of focus, can up-regulate processing of focused constituents, likely to give prominence to the relevant aspects of the input. This is hypothesized to be universal, regardless of the different ways in which languages encode focus. In order to test this universalist hypothesis, we need to go beyond the more familiar linguistic strategies for marking focus, such as by means of intonation or specific syntactic structures (e.g., it-clefts). Therefore, in this study, we examine Makhuwa-Enahara, a Bantu language spoken in northern Mozambique, which uniquely marks focus through verbal conjugation. The participants were presented with sentences that consisted of either a semantically anomalous constituent or a semantically nonanomalous constituent. Moreover, focus on this particular constituent could be either present or absent. We observed a consistent pattern: Focused information generated a more negative N400 response than the same information in nonfocus position. This demonstrates that regardless of how focus is marked, its consequence seems to result in an upregulation of processing of information that is in focus.

Abstract

Timing is an essential part of human cognition and of everyday life activities, such as walking or holding a conversation. Previous studies showed that traumatic brain injury (TBI) often affects cognitive functions such as processing speed and time-sensitive abilities, causing long-term sequelae as well as daily impairments. However, the existing evidence on timing capacities in TBI is mostly limited to perception and the processing of isolated intervals. It is therefore open whether the observed deficits extend to motor timing and to continuous dynamic tasks that more closely match daily life activities. The current study set out to answer these questions by assessing audio motor timing abilities and their relationship with cognitive functioning in a group of TBI patients (n=15) and healthy matched controls. We employed a comprehensive set of tasks aiming at testing timing abilities across perception and production and from single intervals to continuous auditory sequences. In line with previous research, we report functional impairments in TBI patients concerning cognitive processing speed and perceptual timing. Critically, these deficits extended to motor timing: The ability to adjust to tempo changes in an auditory pacing sequence was impaired in TBI patients, and this motor timing deficit covaried with measures of processing speed. These findings confirm previous evidence on perceptual and cognitive timing deficits resulting from TBI and provide first evidence for comparable deficits in motor behavior. This suggests basic co-occurring perceptual and motor timing impairments that may factor into a wide range of daily activities. Our results thus place TBI into the wider range of pathologies with well-documented timing deficits (such as Parkinson’s disease) and encourage the search for novel timing-based therapeutic interventions (e.g., employing dynamic and/or musical stimuli) with high transfer potential to everyday life activities.

Abstract

To understand why music is structured the way it is, we need an explanation that accounts for both the universality and variability found in musical traditions. Here we test whether statistical universals that have been identified for melodic structures in music can emerge as a result of cultural adaptation to human biases through iterated learning. We use data from an experiment in which artificial whistled systems, where sounds were produced with a slide whistle, were learned by human participants and transmitted multiple times from person to person. These sets of whistled signals needed to be memorized and recalled and the reproductions of one participant were used as the input set for the next. We tested for the emergence of seven different melodic features, such as discrete pitches, motivic patterns, or phrase repetition, and found some evidence for the presence of most of these statistical universals. We interpret this as promising evidence that, similarly to rhythmic universals, iterated learning experiments can also unearth melodic statistical universals. More, ideally cross-cultural, experiments are nonetheless needed. Simulating the cultural transmission of artificial proto-musical systems can help unravel the origins of universal tendencies in musical structures.

Abstract

Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) are complex co-occurring neurodevelopmental conditions. Their genetic architectures reveal striking similarities but also differences, including strong, discordant polygenic associations with educational attainment (EA). To study genetic mechanisms that present as ASD-related positive and ADHD-related negative genetic correlations with EA, we carry out multivariable regression analyses using genome-wide summary statistics (N = 10,610–766,345). Our results show that EA-related genetic variation is shared across ASD and ADHD architectures, involving identical marker alleles. However, the polygenic association profile with EA, across shared marker alleles, is discordant for ASD versus ADHD risk, indicating independent effects. At the single-variant level, our results suggest either biological pleiotropy or co-localisation of different risk variants, implicating MIR19A/19B microRNA mechanisms. At the polygenic level, they point to a polygenic form of pleiotropy that contributes to the detectable genome-wide correlation between ASD and ADHD and is consistent with effect cancellation across EA-related regions.

Abstract

Background

The heritability of language and literacy skills increases from early‐childhood to adolescence. The underlying mechanisms are little understood and may involve (a) the amplification of genetic influences contributing to early language abilities, and/or (b) the emergence of novel genetic factors (innovation). Here, we investigate the developmental origins of genetic factors influencing mid‐childhood/early‐adolescent language and literacy. We evaluate evidence for the amplification of early‐childhood genetic factors for vocabulary, in addition to genetic innovation processes.
Methods

Expressive and receptive vocabulary scores at 38 months, thirteen language‐ and literacy‐related abilities and nonverbal cognition (7–13 years) were assessed in unrelated children from the Avon Longitudinal Study of Parents and Children (ALSPAC, Nindividuals ≤ 6,092). We investigated the multivariate genetic architecture underlying early‐childhood expressive and receptive vocabulary, and each of 14 mid‐childhood/early‐adolescent language, literacy or cognitive skills with trivariate structural equation (Cholesky) models as captured by genome‐wide genetic relationship matrices. The individual path coefficients of the resulting structural models were finally meta‐analysed to evaluate evidence for overarching patterns.
Results

We observed little support for the emergence of novel genetic sources for language, literacy or cognitive abilities during mid‐childhood or early adolescence. Instead, genetic factors of early‐childhood vocabulary, especially those unique to receptive skills, were amplified and represented the majority of genetic variance underlying many of these later complex skills (≤99%). The most predictive early genetic factor accounted for 29.4%(SE = 12.9%) to 45.1%(SE = 7.6%) of the phenotypic variation in verbal intelligence and literacy skills, but also for 25.7%(SE = 6.4%) in performance intelligence, while explaining only a fraction of the phenotypic variation in receptive vocabulary (3.9%(SE = 1.8%)).
Conclusions

Genetic factors contributing to many complex skills during mid‐childhood and early adolescence, including literacy, verbal cognition and nonverbal cognition, originate developmentally in early‐childhood and are captured by receptive vocabulary. This suggests developmental genetic stability and overarching aetiological mechanisms.

Abstract

Individual differences in early-life vocabulary measures are heritable and associated with subsequent reading and cognitive abilities, although the underlying mechanisms are little understood. Here, we (i) investigate the developmental genetic architecture of expressive and receptive vocabulary in early-life and (ii) assess timing of emerging genetic associations with mid-childhood verbal and non-verbal skills. We studied longitudinally assessed early-life vocabulary measures (15–38 months) and later-life verbal and non-verbal skills (7–8 years) in up to 6,524 unrelated children from the population-based Avon Longitudinal Study of Parents and Children (ALSPAC) cohort. We dissected the phenotypic variance of rank-transformed scores into genetic and residual components by fitting multivariate structural equation models to genome-wide genetic-relationship matrices. Our findings show that the genetic architecture of early-life vocabulary involves multiple distinct genetic factors. Two of these genetic factors are developmentally stable and also contribute to genetic variation in mid-childhood skills: One genetic factor emerging with expressive vocabulary at 24 months (path coefficient: 0.32(SE = 0.06)) was also related to later-life reading (path coefficient: 0.25(SE = 0.12)) and verbal intelligence (path coefficient: 0.42(SE = 0.13)), explaining up to 17.9% of the phenotypic variation. A second, independent genetic factor emerging with receptive vocabulary at 38 months (path coefficient: 0.15(SE = 0.07)), was more generally linked to verbal and non-verbal cognitive abilities in mid-childhood (reading path coefficient: 0.57(SE = 0.07); verbal intelligence path coefficient: 0.60(0.10); performance intelligence path coefficient: 0.50(SE = 0.08)), accounting for up to 36.1% of the phenotypic variation and the majority of genetic variance in these later-life traits (≥66.4%). Thus, the genetic foundations of mid-childhood reading and cognitive abilities are diverse. They involve at least two independent genetic factors that emerge at different developmental stages during early language development and may implicate differences in cognitive processes that are already detectable during toddlerhood.

Abstract

Background

The number of words children produce (expressive vocabulary) and understand (receptive vocabulary) changes rapidly during early development, partially due to genetic factors. Here, we performed a meta–genome-wide association study of vocabulary acquisition and investigated polygenic overlap with literacy, cognition, developmental phenotypes, and neurodevelopmental conditions, including attention-deficit/hyperactivity disorder (ADHD).

Methods

We studied 37,913 parent-reported vocabulary size measures (English, Dutch, Danish) for 17,298 children of European descent. Meta-analyses were performed for early-phase expressive (infancy, 15–18 months), late-phase expressive (toddlerhood, 24–38 months), and late-phase receptive (toddlerhood, 24–38 months) vocabulary. Subsequently, we estimated single nucleotide polymorphism–based heritability (SNP-h2) and genetic correlations (rg) and modeled underlying factor structures with multivariate models.

Results

Early-life vocabulary size was modestly heritable (SNP-h2 = 0.08–0.24). Genetic overlap between infant expressive and toddler receptive vocabulary was negligible (rg = 0.07), although each measure was moderately related to toddler expressive vocabulary (rg = 0.69 and rg = 0.67, respectively), suggesting a multifactorial genetic architecture. Both infant and toddler expressive vocabulary were genetically linked to literacy (e.g., spelling: rg = 0.58 and rg = 0.79, respectively), underlining genetic similarity. However, a genetic association of early-life vocabulary with educational attainment and intelligence emerged only during toddlerhood (e.g., receptive vocabulary and intelligence: rg = 0.36). Increased ADHD risk was genetically associated with larger infant expressive vocabulary (rg = 0.23). Multivariate genetic models in the ALSPAC (Avon Longitudinal Study of Parents and Children) cohort confirmed this finding for ADHD symptoms (e.g., at age 13; rg = 0.54) but showed that the association effect reversed for toddler receptive vocabulary (rg = −0.74), highlighting developmental heterogeneity.

Conclusions

The genetic architecture of early-life vocabulary changes during development, shaping polygenic association patterns with later-life ADHD, literacy, and cognition-related traits.

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

How learning affects vocalizations is a key question in the study of animal
communication and human language. Parallel efforts in birds and humans
have taught us much about how vocal learning works on a behavioural
and neurobiological level. Subsequent efforts have revealed a variety of
cases among mammals in which experience also has a major influence on
vocal repertoires. Janik and Slater (Anim. Behav. 60, 1–11. (doi:10.1006/
anbe.2000.1410)) introduced the distinction between vocal usage and pro-
duction learning, providing a general framework to categorize how
different types of learning influence vocalizations. This idea was built on
by Petkov and Jarvis (Front. Evol. Neurosci. 4, 12. (doi:10.3389/fnevo.2012.
00012)) to emphasize a more continuous distribution between limited and
more complex vocal production learners. Yet, with more studies providing
empirical data, the limits of the initial frameworks become apparent.
We build on these frameworks to refine the categorization of vocal learning
in light of advances made since their publication and widespread agreement
that vocal learning is not a binary trait. We propose a novel classification
system, based on the definitions by Janik and Slater, that deconstructs
vocal learning into key dimensions to aid in understanding the mechanisms
involved in this complex behaviour. We consider how vocalizations can
change without learning, and a usage learning framework that considers
context specificity and timing. We identify dimensions of vocal production
learning, including the copying of auditory models (convergence/
divergence on model sounds, accuracy of copying), the degree of change
(type and breadth of learning) and timing (when learning takes place, the
length of time it takes and how long it is retained). We consider grey
areas of classification and current mechanistic understanding of these beha-
viours. Our framework identifies research needs and will help to inform
neurobiological and evolutionary studies endeavouring to uncover the
multi-dimensional nature of vocal learning.
This article is part of the theme issue ‘Vocal learning in animals and
humans’.

Abstract

Three experiments investigated semantic and syntactic effects in the production of phrases in Dutch. Bilingual participants were presented with English nouns and were asked to produce an adjective + noun phrase in Dutch including the translation of the noun. In 2 experiments, the authors blocked items by either semantic category or grammatical gender. Participants performed the task slower when the target nouns were of the same semantic category than when they were from different categories and faster when the target nouns had the same gender than when they had different genders. In a final experiment, both manipulations were crossed. The authors replicated the results of the first 2 experiments, and no interaction was found. These findings suggest a feedforward flow of activation between lexico-semantic and lexico-syntactic information.

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

Graded interference effects were tested in a naming task, in parallel for objects and actions. Participants named either object or action pictures presented in the context of other pictures (blocks) that were either semantically very similar, or somewhat semantically similar or semantically dissimilar. We found that naming latencies for both object and action words were modulated by the semantic similarity between the exemplars in each block, providing evidence in both domains of graded semantic effects.

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

As they develop into mature speakers of their native language, infants must not only learn words but also the sounds that make up those words. To do so, they must strike a balance between accepting speaker dependent variation (e.g. mood, voice, accent), but appropriately rejecting variation when it (potentially) changes a word's meaning (e.g. cat vs. hat). This meta-analysis focuses on studies investigating infants' ability to detect mispronunciations in familiar words, or mispronunciation sensitivity. Our goal was to evaluate the development of infants' phonological representations for familiar words as well as explore the role of experimental manipulations related to theoretical questions and analysis choices. The results show that although infants are sensitive to mispronunciations, they still accept these altered forms as labels for target objects. Interestingly, this ability is not modulated by age or vocabulary size, suggesting that a mature understanding of native language phonology may be present in infants from an early age, possibly before the vocabulary explosion. These results also support several theoretical assumptions made in the literature, such as sensitivity to mispronunciation size and position of the mispronunciation. We also shed light on the impact of data analysis choices that may lead to different conclusions regarding the development of infants' mispronunciation sensitivity. Our paper concludes with recommendations for improved practice in testing infants' word and sentence processing on-line.