Publications

Abstract

The present study provides Dutch norms for age of acquisition, familiarity, imageability, image agreement, visual complexity, word frequency, and word length (in syllables) for 124 line drawings of actions. Ratings were obtained from 117 Dutch participants. Word frequency was determined on the basis of the SUBTLEX-NL corpus (Keuleers, Brysbaert, & New, Behavior Research Methods, 42, 643–650, 2010). For 104 of the pictures, naming latencies and name agreement were determined in a separate naming experiment with 74 native speakers of Dutch. The Dutch norms closely corresponded to the norms for British English. Multiple regression analysis showed that age of acquisition, imageability, image agreement, visual complexity, and name agreement were significant predictors of naming latencies, whereas word frequency and word length were not. Combined with the results of a principal-component analysis, these findings suggest that variables influencing the processes of conceptual preparation and lexical selection affect latencies more strongly than do variables influencing word-form encoding.

Abstract

This study examined the contributions of verbal ability and executive control to verbal fluency performance in older adults (n=82). Verbal fluency was assessed in letter and category fluency tasks, and performance on these tasks was related to indicators of vocabulary size, lexical access speed, updating, and inhibition ability. In regression analyses the number of words produced in both fluency tasks was predicted by updating ability, and the speed of the first response was predicted by vocabulary size and, for category fluency only, lexical access speed. These results highlight the hybrid character of both fluency tasks, which may limit their usefulness for research and clinical purposes.

Abstract

Dissociations in the ability to produce words of different grammatical categories are well established in neuropsychology but have not been corroborated fully with evidence from brain imaging. Here we report on a PET study designed to reveal the anatomical correlates of grammatical processes involving nouns and verbs. German-speaking subjects were asked to produce either plural and singular nouns, or first-person plural and singular verbs. Verbs, relative to nouns, activated a left frontal cortical network, while the opposite contrast (nouns–verbs) showed greater activation in temporal regions bilaterally. Similar patterns emerged when subjects performed the task with pseudowords used as nouns or as verbs. These results converge with findings from lesion studies and suggest that grammatical category is an important dimension of organization for knowledge of language in the brain.

Abstract

Positron emission tomography was used to investigate two competing hypotheses about the role of the left inferior frontal gyrus (IFG) in word generation. One proposes a domain-specific organization, with neural activation dependent on the type of information being processed, i.e., surface sound structure or semantic. The other proposes a process-specific organization, with activation dependent on processing demands, such as the amount of selection needed to decide between competing lexical alternatives. In a novel word retrieval task, word reconstruction (WR), subjects generated real words from heard non-words by the substitution of either a vowel or consonant. Both types of lexical retrieval, informed by sound structure alone, produced activation within anterior and posterior left IFG regions. Within these regions there was greater activity for consonant WR, which is more difficult and imposes greater processing demands. These results support a process-specific organization of the anterior left IFG.

Abstract

Models of speech production disagree on whether or not homonyms have a shared word-form representation. To investigate this issue, a picture-naming experiment was carried out using Dutch homonyms of which both meanings could be presented as a picture. Naming latencies for the low-frequency meanings of homonyms were slower than for those of the high-frequency meanings. However, no frequency effect was found for control words, which matched the frequency of the homonyms meanings. Subsequent control experiments indicated that the difference in naming latencies for the homonyms could be attributed to processes earlier than wordform retrieval. Specifically, it appears that low name agreement slowed down the naming of the low-frequency homonym pictures.

Abstract

Pitch is often described metaphorically: for example, Farsi and Turkish speakers use a ‘thickness’ metaphor (low sounds are ‘thick’ and high sounds are ‘thin’), while German and English speakers use a height metaphor (‘low’, ‘high’). This study examines how child and adult speakers of Farsi, Turkish, and German map pitch and thickness using a cross-modal association task. All groups, except for German children, performed significantly better than chance. German-speaking adults’ success suggests the pitch-to-thickness association can be learned by experience. But the fact that German children were at chance indicates that this learning takes time. Intriguingly, Farsi and Turkish children's performance suggests that learning cross-modal associations can be boosted through experience with consistent metaphorical mappings in the input language

Abstract

Contrary to linear difference equations, there is no general theory of difference equations of the form G(P(x−τ1),…,P(x−τs))+G0(x)=0, with τi∈K, G(x1,…,xs)∈K[x1,…,xs] of total degree D⩾2 and G0(x)∈K[x], where K is a field of characteristic zero. This article is concerned with the following problem: given τi, G and G0, find an upper bound on the degree d of a polynomial solution P(x), if it exists. In the presented approach the problem is reduced to constructing a univariate polynomial for which d is a root. The authors formulate a sufficient condition under which such a polynomial exists. Using this condition, they give an effective bound on d, for instance, for all difference equations of the form G(P(x−a),P(x−a−1),P(x−a−2))+G0(x)=0 with quadratic G, and all difference equations of the form G(P(x),P(x−τ))+G0(x)=0 with G having an arbitrary degree.

Abstract

In conversation, the initial pitch of an utterance can provide an early phonetic cue of the communicative function, the speech act, or the social action being implemented. We conducted quantitative acoustic measurements and statistical analyses of pitch in over 10,000 utterances, including 2512 questions, their responses, and about 5000 other utterances by 180 total speakers from a corpus of 70 natural conversations in 10 languages. We measured pitch at first prominence in a speaker’s utterance and discriminated utterances by language, speaker, gender, question form, and what social action is achieved by the speaker’s turn. Through applying multivariate logistic regression we found that initial pitch that significantly deviated from the speaker’s median pitch level was predictive of the social action of the question. In questions designed to solicit agreement with an evaluation rather than information, pitch was divergent from a speaker’s median predictably in the top 10% of a speakers range. This latter finding reveals a kind of iconicity in the relationship between prosody and social action in which a marked pitch correlates with a marked social action. Thus, we argue that speakers rely on pitch to provide an early signal for recipients that the question is not to be interpreted through its literal semantics but rather through an inference.

Abstract

We investigated global integration (wrap-up) processes at the boundaries of musical phrases by comparing the effects of well and non-well formed phrases on event-related potentials time-locked to two boundary points: the onset and the offset of the boundary pause. The Closure Positive Shift, which is elicited at the boundary offset, was not modulated by the quality of phrase structure (well vs. non-well formed). In contrast, the boundary onset potentials showed different patterns for well and non-well formed phrases. Our results contribute to specify the functional meaning of the Closure Positive Shift in music, shed light on the large-scale structural integration of musical input, and raise new hypotheses concerning shared resources between music and language.

Abstract

Neuroscientific and musicological approaches to music cognition indicate that listeners familiarized in the Western tonal tradition expect a musical phrase boundary at predictable time intervals. However, phrase boundary prediction processes in music remain untested. We analyzed event-related potentials (ERPs) and event-related induced power changes at the onset and offset of a boundary pause. We made comparisons with modified melodies, where the pause was omitted and filled by tones. The offset of the pause elicited a closure positive shift (CPS), indexing phrase boundary detection. The onset of the filling tones elicited significant increases in theta and beta powers. In addition, the P2 component was larger when the filling tones started than when they ended. The responses to boundary omission suggest that listeners expected to hear a boundary pause. Therefore, boundary prediction seems to coexist with boundary detection in music segmentation.

Abstract

An ability to decode semantic information from fMRI spatial patterns has been demonstrated in previous studies mostly for 1 specific input modality. In this study, we aimed to decode semantic category independent of the modality in which an object was presented. Using a searchlight method, we were able to predict the stimulus category from the data while participants performed a semantic categorization task with 4 stimulus modalities (spoken and written names, photographs, and natural sounds). Significant classification performance was achieved in all 4 modalities. Modality-independent decoding was implemented by training and testing the searchlight method across modalities. This allowed the localization of those brain regions, which correctly discriminated between the categories, independent of stimulus modality. The analysis revealed large clusters of voxels in the left inferior temporal cortex and in frontal regions. These voxels also allowed category discrimination in a free recall session where subjects recalled the objects in the absence of external stimuli. The results show that semantic information can be decoded from the fMRI signal independently of the input modality and have clear implications for understanding the functional mechanisms of semantic memory.

Abstract

In this study, we explore the possibility to predict the semantic category of words from brain signals in a free word generation task. Participants produced single words from different semantic categories in a modified semantic fluency task. A Bayesian logistic regression classifier was trained to predict the semantic category of words from single-trial MEG data. Significant classification accuracies were achieved using sensor-level MEG time series at the time interval of conceptual preparation. Semantic category prediction was also possible using source-reconstructed time series, based on minimum norm estimates of cortical activity. Brain regions that contributed most to classification on the source level were identified. These were the left inferior frontal gyrus, left middle frontal gyrus, and left posterior middle temporal gyrus. Additionally, the temporal dynamics of brain activity underlying the semantic preparation during word generation was explored. These results provide important insights about central aspects of language production

Abstract

This study examines what stage 9‐12‐year‐old Dutch‐speaking children have reached in the development of their L2 lexicon, focusing on its phonological specificity. Two experiments were carried out with a group of Dutch‐speaking children and adults learning English. In a first task, listeners were asked to judge Dutch words which were presented with either the target Dutch vowel or with an English vowel synthetically inserted. The second experiment was a mirror of the first, i.e. with English words and English or Dutch vowels inserted. It was examined to what extent the listeners accepted substitutions of Dutch vowels by English ones, and vice versa. The results of the experiments suggest that the children have not reached the same degree of phonological specificity of L2 words as the adults. Children not only experience a strong influence of their native vowel categories when listening to L2 words, they also apply less strict criteria.

Abstract

This study investigated the phonological representations of vowels in children's native and non-native lexicons. Two experiments were mispronunciation tasks (i.e., a vowel in words was substituted by another vowel from the same language). These were carried out by Dutch-speaking 9–12-year-old children and Dutch-speaking adults, in their native (Experiment 1, Dutch) and non-native (Experiment 2, English) language. A third experiment tested vowel discrimination. In Dutch, both children and adults could accurately detect mispronunciations. In English, adults, and especially children, detected substitutions of native vowels (i.e., vowels that are present in the Dutch inventory) by non-native vowels more easily than changes in the opposite direction. Experiment 3 revealed that children could accurately discriminate most of the vowels. The results indicate that children's L1 categories strongly influenced their perception of English words. However, the data also reveal a hint of the development of L2 phoneme categories.

Abstract

An exploratory genome-wide copy number variant (CNV) study was performed in 127 independent cases with specific language impairment (SLI), their first-degree relatives (385 individuals) and 269 population controls. Language-impaired cases showed an increased CNV burden in terms of the average number of events (11.28 vs 10.01, empirical P=0.003), the total length of CNVs (717 vs 513 Kb, empirical P=0.0001), the average CNV size (63.75 vs 51.6 Kb, empirical P=0.0005) and the number of genes spanned (14.29 vs 10.34, empirical P=0.0007) when compared with population controls, suggesting that CNVs may contribute to SLI risk. A similar trend was observed in first-degree relatives regardless of affection status. The increased burden found in our study was not driven by large or de novo events, which have been described as causative in other neurodevelopmental disorders. Nevertheless, de novo CNVs might be important on a case-by-case basis, as indicated by identification of events affecting relevant genes, such as ACTR2 and CSNK1A1, and small events within known micro-deletion/-duplication syndrome regions, such as chr8p23.1. Pathway analysis of the genes present within the CNVs of the independent cases identified significant overrepresentation of acetylcholine binding, cyclic-nucleotide phosphodiesterase activity and MHC proteins as compared with controls. Taken together, our data suggest that the majority of the risk conferred by CNVs in SLI is via common, inherited events within a ‘common disorder–common variant’ model. Therefore the risk conferred by CNVs will depend upon the combination of events inherited (both CNVs and SNPs), the genetic background of the individual and the environmental factors.

Abstract

Aim Sex chromosome aneuploidies increase the risk of spoken or written language disorders but individuals with specific language impairment (SLI) or dyslexia do not routinely undergo cytogenetic analysis. We assess the frequency of sex chromosome aneuploidies in individuals with language impairment or dyslexia. Method Genome-wide single nucleotide polymorphism genotyping was performed in three sample sets: a clinical cohort of individuals with speech and language deficits (87 probands: 61 males, 26 females; age range 4 to 23 years), a replication cohort of individuals with SLI, from both clinical and epidemiological samples (209 probands: 139 males, 70 females; age range 4 to 17 years), and a set of individuals with dyslexia (314 probands: 224 males, 90 females; age range 7 to 18 years). Results In the clinical language-impaired cohort, three abnormal karyotypic results were identified in probands (proband yield 3.4%). In the SLI replication cohort, six abnormalities were identified providing a consistent proband yield (2.9%). In the sample of individuals with dyslexia, two sex chromosome aneuploidies were found giving a lower proband yield of 0.6%. In total, two XYY, four XXY (Klinefelter syndrome), three XXX, one XO (Turner syndrome), and one unresolved karyotype were identified. Interpretation The frequency of sex chromosome aneuploidies within each of the three cohorts was increased over the expected population frequency (approximately 0.25%) suggesting that genetic testing may prove worthwhile for individuals with language and literacy problems and normal non-verbal IQ. Early detection of these aneuploidies can provide information and direct the appropriate management for individuals.

Abstract

Listeners have to overcome variability of the speech signal that can arise, for example, because of differences in room acoustics, differences in speakers’ vocal tract properties, or idiosyncrasies in pronunciation. Two mechanisms that are involved in resolving such variation are perceptually contrastive effects that arise from surrounding acoustic context and lexically guided perceptual learning. Although both processes have been studied in great detail, little attention has been paid to how they operate relative to each other in speech perception. The present study set out to address this issue. The carrier parts of exposure stimuli of a classical perceptual learning experiment were spectrally filtered such that the acoustically ambiguous final fricatives sounded relatively more like the lexically intended sound (Experiment 1) or the alternative (Experiment 2). Perceptual learning was found only in the latter case. The findings show that perceptual contrast effects precede lexically guided perceptual learning, at least in terms of temporal order, and potentially in terms of cognitive processing levels as well

Abstract

The smooth transitions between turns in natural conversation suggest that speakers often begin to plan their utterances while listening to their interlocutor. The presented study investigates whether this is indeed the case and, if so, when utterance planning begins. Two hypotheses were contrasted: that speakers begin to plan their turn as soon as possible (in our experiments less than a second after the onset of the interlocutor’s turn), or that they do so close to the end of the interlocutor’s turn. Turn-taking was combined with a finger tapping task to measure variations in cognitive load. We assumed that the onset of speech planning in addition to listening would be accompanied by deterioration in tapping performance. Two picture description experiments were conducted. In both experiments there were three conditions: (1) Tapping and Speaking, where participants tapped a complex pattern while taking over turns from a pre-recorded speaker, (2) Tapping and Listening, where participants carried out the tapping task while overhearing two pre-recorded speakers, and (3) Speaking Only, where participants took over turns as in the Tapping and Speaking condition but without tapping. The experiments differed in the amount of tapping training the participants received at the beginning of the session. In Experiment 2, the participants’ eye-movements were recorded in addition to their speech and tapping. Analyses of the participants’ tapping performance and eye movements showed that they initiated the cognitively demanding aspects of speech planning only shortly before the end of the turn of the preceding speaker. We argue that this is a smart planning strategy, which may be the speakers’ default in many everyday situations.

Abstract

Introduction The ability to identify individuals at increased genetic risk for Alzheimer's disease (AD) may streamline biomarker and drug trials and aid clinical and personal decision making. Methods We evaluated the discriminative ability of a genetic risk score (GRS) covering 22 published genetic risk loci for AD in 1162 Flanders-Belgian AD patients and 1019 controls and assessed correlations with family history, onset age, and cerebrospinal fluid (CSF) biomarkers (Aβ1-42, T-Tau, P-Tau181P). Results A GRS including all single nucleotide polymorphisms (SNPs) and age-specific APOE ε4 weights reached area under the curve (AUC) 0.70, which increased to AUC 0.78 for patients with familial predisposition. Risk of AD increased with GRS (odds ratio, 2.32 (95% confidence interval 2.08-2.58 per unit; P < 1.0e-15). Onset age and CSF Aβ1-42 decreased with increasing GRS (Ponset-age = 9.0e-11; PAβ = 8.9e-7). Discussion The discriminative ability of this 22-SNP GRS is still limited, but these data illustrate that incorporation of age-specific weights improves discriminative ability. GRS-phenotype correlations highlight the feasibility of identifying individuals at highest susceptibility. © 2015 The Authors.

Abstract

Crosslinguistic studies of expressions of motion events have found that Talmy's binary typology of verb-framed and satellite-framed languages is reflected in language use. In particular, Manner of motion is relatively more elaborated in satellite-framed languages (e.g., in narrative, picture description, conversation, translation). The present research builds on previous controlled studies of the domain of human motion by eliciting descriptions of a wide range of manners of walking and running filmed in natural circumstances. Descriptions were elicited from speakers of two satellite-framed languages (English, Polish) and three verb-framed languages (French, Spanish, Basque). The sampling of events in this study resulted in four major semantic clusters for these five languages: walking, running, non-canonical gaits (divided into bounce-and-recoil and syncopated movements), and quadrupedal movement (crawling). Counts of verb types found a broad tendency for satellite-framed languages to show greater lexical diversity, along with substantial within group variation. Going beyond most earlier studies, we also examined extended descriptions of manner of movement, isolating types of manner. The following categories of manner were identified and compared: attitude of actor, rate, effort, posture, and motor patterns of legs and feet. Satellite-framed speakers tended to elaborate expressive manner verbs, whereas verb-framed speakers used modification to add manner to neutral motion verbs

Abstract

Spinocerebellar ataxia type 23 is caused by mutations in PDYN, which encodes the opioid neuropeptide precursor protein, prodynorphin. Prodynorphin is processed into the opioid peptides, α-neoendorphin, and dynorphins A and B, that normally exhibit opioid-receptor mediated actions in pain signalling and addiction. Dynorphin A is likely a mutational hotspot for spinocerebellar ataxia type 23 mutations, and in vitro data suggested that dynorphin A mutations lead to persistently elevated mutant peptide levels that are cytotoxic and may thus play a crucial role in the pathogenesis of spinocerebellar ataxia type 23. To further test this and study spinocerebellar ataxia type 23 in more detail, we generated a mouse carrying the spinocerebellar ataxia type 23 mutation R212W in PDYN. Analysis of peptide levels using a radioimmunoassay shows that these PDYNR212W mice display markedly elevated levels of mutant dynorphin A, which are associated with climber fibre retraction and Purkinje cell loss, visualized with immunohistochemical stainings. The PDYNR212W mice reproduced many of the clinical features of spinocerebellar ataxia type 23, with gait deficits starting at 3 months of age revealed by footprint pattern analysis, and progressive loss of motor coordination and balance at the age of 12 months demonstrated by declining performances on the accelerating Rotarod. The pathologically elevated mutant dynorphin A levels in the cerebellum coincided with transcriptionally dysregulated ionotropic and metabotropic glutamate receptors and glutamate transporters, and altered neuronal excitability. In conclusion, the PDYNR212W mouse is the first animal model of spinocerebellar ataxia type 23 and our work indicates that the elevated mutant dynorphin A peptide levels are likely responsible for the initiation and progression of the disease, affecting glutamatergic signalling, neuronal excitability, and motor performance. Our novel mouse model defines a critical role for opioid neuropeptides in spinocerebellar ataxia, and suggests that restoring the elevated mutant neuropeptide levels can be explored as a therapeutic intervention.

Abstract

Cerebellar ataxias are progressive neurodegenerative disorders characterized by atrophy of the cerebellum leading to motor dysfunction, balance problems, and limb and gait ataxia. These include among others, the dominantly inherited spinocerebellar ataxias, recessive cerebellar ataxias such as Friedreich's ataxia, and X-linked cerebellar ataxias. Since all cerebellar ataxias display considerable overlap in their disease phenotypes, common pathological pathways must underlie the selective cerebellar neurodegeneration. Therefore, it is important to identify the molecular mechanisms and routes to neurodegeneration that cause cerebellar ataxia. In this review, we discuss the use of functional genomic approaches including whole-exome sequencing, genome-wide gene expression profiling, miRNA profiling, epigenetic profiling, and genetic modifier screens to reveal the underlying pathogenesis of various cerebellar ataxias. These approaches have resulted in the identification of many disease genes, modifier genes, and biomarkers correlating with specific stages of the disease. This article is part of a Special Issue entitled: From Genome to Function.

Abstract

Learning to read and write requires an individual to connect additional orthographic representations to pre-existing mappings between phonological and semantic representations of words. Past empirical results suggest that the process of learning to read and write (at least in alphabetic languages) elicits changes in the language processing system, by either increasing the cognitive efficiency of mapping between representations associated with a word, or by changing the granularity of phonological processing of spoken language, or through a combination of both. Behavioural effects of literacy have typically been assessed in offline explicit tasks that have addressed only phonological processing. However, a recent eye tracking study compared high and low literate participants on effects of phonology and semantics in processing measured implicitly using eye movements. High literates’ eye movements were more affected by phonological overlap in online speech than low literates, with only subtle differences observed in semantics. We determined whether these effects were due to cognitive efficiency and/or granularity of speech processing in a multimodal model of speech processing – the amodal shared resource model (ASR, Smith, Monaghan, & Huettig, 2013). We found that cognitive efficiency in the model had only a marginal effect on semantic processing and did not affect performance for phonological processing, whereas fine-grained versus coarse-grained phonological representations in the model simulated the high/low literacy effects on phonological processing, suggesting that literacy has a focused effect in changing the grain-size of phonological mappings.

Abstract

A quantitative model of human categorization behavior is proposed, which can be applied to 4-alternative forced-choice categorization data involving two binary classifications. A number of processing dependencies between the two classifications are explicitly formulated, such as the dependence of the location, orientation, and steepness of the class boundary for one classification on the outcome of the other classification. The significance of various types of dependencies can be tested statistically. Analyses of a data set from the literature shows that interesting dependencies in human speech recognition can be uncovered using the model.

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

Humans have a strong proclivity for structuring and patterning stimuli: Whether in space or time, we tend to mentally order stimuli in our environment and organize them into units with specific types of relationships. A crucial prerequisite for such organization is the cognitive ability to discern and process regularities among multiple stimuli. To investigate the evolutionary roots of this cognitive capacity, we tested chimpanzees—which, along with bonobos, are our closest living relatives—for simple, variable distance dependency processing in visual patterns. We trained chimpanzees to identify pairs of shapes either linked by an arbitrary learned association (arbitrary associative dependency) or a shared feature (same shape, feature-based dependency), and to recognize strings where items related to either of these ways occupied the first (leftmost) and the last (rightmost) item of the stimulus. We then probed the degree to which subjects generalized this pattern to new colors, shapes, and numbers of interspersed items. We found that chimpanzees can learn and generalize both types of dependency rules, indicating that the ability to encode both feature-based and arbitrary associative regularities over variable distances in the visual domain is not a human prerogative. Our results strongly suggest that these core components of human structural processing were already present in our last common ancestor with chimpanzees.

Abstract

Flexibly adapting social behavior to social and environmental challenges helps to alleviate glucocorticoid (GC) levels, which may have positive fitness implications for an individual. For primates, the predominant social behavior is grooming. Giving grooming to others is particularly efficient in terms of GC mitigation. However, grooming is confined by certain limitations such as time constraints or restricted access to other group members. For instance, dominance hierarchies may impact grooming partner availability in primate societies. Consequently specific grooming patterns emerge. In despotic species focusing grooming activity on preferred social partners significantly ameliorates GC levels in females of all ranks. In this study we investigated grooming patterns and GC management in Barbary macaques, a comparably relaxed species. We monitored changes in grooming behavior and cortisol (C) for females of different ranks. Our results show that the C‐amelioration associated with different grooming patterns had a gradual connection with dominance hierarchy: while higher‐ranking individuals showed lowest urinary C measures when they focused their grooming on selected partners within their social network, lower‐ranking individuals expressed lowest C levels when dispersing their grooming activity evenly across their social partners. We argue that the relatively relaxed social style of Barbary macaque societies allows individuals to flexibly adapt grooming patterns, which is associated with rank‐specific GC management. Am. J. Primatol. 77:688–700, 2015

Abstract

The auditory scene is a mental representation of individual sounds extracted from the summed sound waveform reaching the ears of the listeners. Musical contexts represent particularly complex cases of auditory scenes. In such a scenario, melody may be seen as the main object moving on a background represented by the accompaniment. Both melody and accompaniment vary in time according to harmonic rules, forming a typical texture with melody in the most prominent, salient voice. In the present sparse acquisition functional magnetic resonance imaging study, we investigated the interplay between melody and accompaniment in trained pianists, by observing the activation responses elicited by processing: (1) melody placed in the upper and lower texture voices, leading to, respectively, a higher and lower auditory salience; (2) harmonic violations occurring in either the melody, the accompaniment, or both. The results indicated that the neural activation elicited by the processing of polyphonic compositions in expert musicians depends upon the upper versus lower position of the melodic line in the texture, and showed an overall greater activation for the harmonic processing of melody over accompaniment. Both these two predominant effects were characterized by the involvement of the posterior cingulate cortex and precuneus, among other associative brain regions. We discuss the prominent role of the posterior medial cortex in the processing of melodic and harmonic information in the auditory stream, and propose to frame this processing in relation to the cognitive construction of complex multimodal sensory imagery scenes.

Abstract

Aims/hypothesis Several forkhead box (FOX) transcription factor family members have important roles in controlling pancreatic cell fates and maintaining beta cell mass and function, including FOXA1, FOXA2 and FOXM1. In this study we have examined the importance of FOXP1, FOXP2 and FOXP4 of the FOXP subfamily in islet cell development and function. Methods Mice harbouring floxed alleles for Foxp1, Foxp2 and Foxp4 were crossed with pan-endocrine Pax6-Cre transgenic mice to generate single and compound Foxp mutant mice. Mice were monitored for changes in glucose tolerance by IPGTT, serum insulin and glucagon levels by radioimmunoassay, and endocrine cell development and proliferation by immunohistochemistry. Gene expression and glucose-stimulated hormone secretion experiments were performed with isolated islets. Results Only the triple-compound Foxp1/2/4 conditional knockout (cKO) mutant had an overt islet phenotype, manifested physiologically by hypoglycaemia and hypoglucagonaemia. This resulted from the reduction in glucagon-secreting alpha cell mass and function. The proliferation of alpha cells was profoundly reduced in Foxp1/2/4 cKO islets through the effects on mediators of replication (i.e. decreased Ccna2, Ccnb1 and Ccnd2 activators, and increased Cdkn1a inhibitor). Adult islet Foxp1/2/4 cKO beta cells secrete insulin normally while the remaining alpha cells have impaired glucagon secretion. Conclusions/interpretation Collectively, these findings reveal an important role for the FOXP1, 2, and 4 proteins in governing postnatal alpha cell expansion and function.

Abstract

OBJECTIVE: Genome-wide association studies (GWAS) of BMI are mostly undertaken under the assumption that "kg/m(2) " is an index of weight fully adjusted for height, but in general this is not true. The aim here was to assess the contribution of common genetic variation to a adjusted version of that phenotype which appropriately accounts for covariation in height in children. METHODS: A GWAS of height-adjusted BMI (BMI[x] = weight/height(x) ), calculated to be uncorrelated with height, in 5809 participants (mean age 9.9 years) from the Avon Longitudinal Study of Parents and Children (ALSPAC) was performed. RESULTS: GWAS based on BMI[x] yielded marked differences in genomewide results profile. SNPs in ADCY3 (adenylate cyclase 3) were associated at genome-wide significance level (rs11676272 (0.28 kg/m(3.1) change per allele G (0.19, 0.38), P = 6 × 10(-9) ). In contrast, they showed marginal evidence of association with conventional BMI [rs11676272 (0.25 kg/m(2) (0.15, 0.35), P = 6 × 10(-7) )]. Results were replicated in an independent sample, the Generation R study. CONCLUSIONS: Analysis of BMI[x] showed differences to that of conventional BMI. The association signal at ADCY3 appeared to be driven by a missense variant and it was strongly correlated with expression of this gene. Our work highlights the importance of well understood phenotype use (and the danger of convention) in characterising genetic contributions to complex traits.

Abstract

While a training model of cognitive intervention targets the improvement of particular skills through instruction and practice, an engagement model is based on the idea that being embedded in an intellectually and socially complex environment can impact cognition, perhaps even broadly, without explicit instruction. We contrasted these 2 models of cognitive enrichment by randomly assigning healthy older adults to a home-based inductive reasoning training program, a team-based competitive program in creative problem solving, or a wait-list control. As predicted, those in the training condition showed selective improvement in inductive reasoning. Those in the engagement condition, on the other hand, showed selective improvement in divergent thinking, a key ability exercised in creative problem solving. On average, then, both groups appeared to show ability-specific effects. However, moderators of change differed somewhat for those in the engagement and training interventions. Generally, those who started either intervention with a more positive cognitive profile showed more cognitive growth, suggesting that cognitive resources enabled individuals to take advantage of environmental enrichment. Only in the engagement condition did initial levels of openness and social network size moderate intervention effects on cognition, suggesting that comfort with novelty and an ability to manage social resources may be additional factors contributing to the capacity to take advantage of the environmental complexity associated with engagement. Collectively, these findings suggest that training and engagement models may offer alternative routes to cognitive resilience in late life

Abstract

This article examines pediatrician-parent interaction in the context of acute pediatric encounters for children with upper respiratory infections. Parents and physicians orient to treatment recommendations as normatively requiring parent acceptance for physicians to close the activity. Through acceptance, withholding of acceptance, or active resistance, parents have resources with which to negotiate for a treatment outcome that is in line with their own wants. This article offers evidence that even in acute care, shared decision making not only occurs but, through normative constraints, is mandated for parents and physicians to reach accord in the treatment decision.

Abstract

In this article I examine one practice speakers have for confirming when confirmation was not otherwise relevant. The practice involves a speaker repeating an assertion previously made by another speaker in modified form with stress on the copula/auxiliary. I argue that these modified repeats work to undermine the first speaker's default ownership and rights over the claim and instead assert the primacy of the second speaker's rights to make the statement. Two types of modified repeats are identified: partial and full. Although both involve competing for primacy of the claim, they occur in distinct sequential environments: The former are generally positioned after a first claim was epistemically downgraded, whereas the latter are positioned following initial claims that were offered straightforwardly, without downgrading.

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

That human social interaction involves the intertwined cooperation of different modalities is uncontroversial. Researchers in several allied fields have, however, only recently begun to document the precise ways in which talk, gesture, gaze, and aspects of the material surround are brought together to form coherent courses of action. The papers in this volume are attempts to develop this line of inquiry. Although the authors draw on a range of analytic, theoretical, and methodological traditions (conversation analysis, ethnography, distributed cognition, and workplace studies), all are concerned to explore and illuminate the inherently multimodal character of social interaction. Recent studies, including those collected in this volume, suggest that different modalities work together not only to elaborate the semantic content of talk but also to constitute coherent courses of action. In this introduction we present evidence for this position. We begin by reviewing some select literature focusing primarily on communicative functions and interactive organizations of specific modalities before turning to consider the integration of distinct modalities in interaction.

Abstract

This study draws on a database of 570 community-based acute pediatric encounters in the USA and uses conversation analysis as a methodology to identify two formats physicians use to recommend non-antibiotic treatment in acute pediatric care (using a subset of 309 cases): recommendations for particular treatment (e.g., “I’m gonna give her some cough medicine.”) and recommendations against particular treatment (e.g., “She doesn’t need any antibiotics.”). The findings are that the presentation of a specific affirmative recommendation for treatment is less likely to engender parent resistance to a non-antibiotic treatment recommendation than a recommendation against particular treatment even if the physician later offers a recommendation for particular treatment. It is suggested that physicians who provide a specific positive treatment recommendation followed by a negative recommendation are most likely to attain parent alignment and acceptance when recommending a non-antibiotic treatment for a viral upper respiratory illness.

Abstract

How can we understand each other during communicative interactions? An influential suggestion holds that communicators are primed by each other’s behaviors, with associative mechanisms automatically coordinating the production of communicative signals and the comprehension of their meanings. An alternative suggestion posits that mutual understanding requires shared conceptualizations of a signal’s use, i.e., “conceptual pacts” that are abstracted away from specific experiences. Both accounts predict coherent neural dynamics across communicators, aligned either to the occurrence of a signal or to the dynamics of conceptual pacts. Using coherence spectral-density analysis of cerebral activity simultaneously measured in pairs of communicators, this study shows that establishing mutual understanding of novel signals synchronizes cerebral dynamics across communicators’ right temporal lobes. This interpersonal cerebral coherence occurred only within pairs with a shared communicative history, and at temporal scales independent from signals’ occurrences. These findings favor the notion that meaning emerges from shared conceptualizations of a signal’s use.

Abstract

Despite the ambiguity inherent in human communication, people are remarkably efficient in establishing mutual understanding. Studying how people communicate in novel settings provides a window into the mechanisms supporting the human competence to rapidly generate and understand novel shared symbols, a fundamental property of human communication. Previous work indicates that the right posterior superior temporal sulcus (pSTS) is involved when people understand the intended meaning of novel communicative actions. Here, we set out to test whether normal functioning of this cerebral structure is required for understanding novel communicative actions using inhibitory low-frequency repetitive transcranial magnetic stimulation (rTMS). A factorial experimental design contrasted two tightly matched stimulation sites (right pSTS vs. left MT+, i.e. a contiguous homotopic task-relevant region) and tasks (a communicative task vs. a visual tracking task that used the same sequences of stimuli). Overall task performance was not affected by rTMS, whereas changes in task performance over time were disrupted according to TMS site and task combinations. Namely, rTMS over pSTS led to a diminished ability to improve action understanding on the basis of recent communicative history, while rTMS over MT+ perturbed improvement in visual tracking over trials. These findings qualify the contributions of the right pSTS to human communicative abilities, showing that this region might be necessary for incorporating previous knowledge, accumulated during interactions with a communicative partner, to constrain the inferential process that leads to action understanding.

Abstract

Thirty-eight 3-, 6-, and 9-month-old infants interacted in a face to face situation with a female stranger who disrupted the on-going interaction with 30 s Happy and Neutral still face episodes. Three- and 6-month-olds manifested a robust still face response for gazing and smiling. For smiling, 9-month-olds manifested a floor effect such that no still face effect could be shown. For gazing, 9-month-olds' still face response was modulated by the context of interaction such that it was less pronounced if a happy still face was presented first. The findings point to a developmental transition by the end of the first year, whereby infants' still face response becomes increasingly influenced by the context of social interaction. (C) 2004 Published by Elsevier Inc. [References: 35]

Abstract

This study investigates whether spoken sentence comprehension deficits in Broca's aphasics results from their inability to access the subordinate meaning of ambiguous words (e.g. bank), or alternatively, from a delay in their selection of the contextually appropriate meaning. Twelve Broca's aphasics and twelve elderly controls were presented with lexical ambiguities in three context conditions, each followed by the same target words. In the concordant condition, the sentence context biased the meaning of the sentence final ambiguous word that was related to the target. In the discordant condition, the sentence context biased the meaning of the sentence final ambiguous word that was incompatible with the target.In the unrelated condition, the sentence-final word was unambiguous and unrelated to the target. The task of the subjects was to listen attentively to the stimuli The activational status of the ambiguous sentence-final words was inferred from the amplitude of the N399 to the targets at two inter-stimulus intervals (ISIs) (100 ms and 1250 ms). At the short ISI, the Broca's aphasics showed clear evidence of activation of the subordinate meaning. In contrast to elderly controls, however, the Broca's aphasics were not successful at selecting the appropriate meaning of the ambiguity in the short ISI version of the experiment. But at the long ISI, in accordance with the performance of the elderly controls, the patients were able to successfully complete the contextual selection process. These results indicate that Broca's aphasics are delayed in the process of contextual selection. It is argued that this finding of delayed selection is compatible with the idea that comprehension deficits in Broca's aphasia result from a delay in the process of integrating lexical information.

Abstract

General knowledge acquisition entails the extraction of statistical regularities from the environment. At high levels of complexity, this may involve the extraction, and consolidation, of associative regularities across event memories. The underlying neural mechanisms would likely involve a hippocampo-neocortical dialog, as proposed previously for system-level consolidation. To test these hypotheses, we assessed possible differences in consolidation between associative memories containing cross-episodic regularities and unique associative memories. Subjects learned face–location associations, half of which responded to complex regularities regarding the combination of facial features and locations, whereas the other half did not. Importantly, regularities could only be extracted over hippocampus-encoded, associative aspects of the items. Memory was assessed both immediately after encoding and 48 h later, under fMRI acquisition. Our results suggest that processes related to system-level reorganization occur preferentially for regular associations across episodes. Moreover, the build-up of general knowledge regarding regular associations appears to involve the coordinated activity of the hippocampus and mediofrontal regions. The putative cross-talk between these two regions might support a mechanism for regularity extraction. These findings suggest that the consolidation of cross-episodic regularities may be a key mechanism underlying general knowledge acquisition.

Abstract

This volume on Inuit speech follows the evolution of a native language of the North American Arctic, from its historical roots to its present-day linguistic structure and patterns of use from Alaska to Greenland. Drawing on a wide range of research from the fields of linguistics, anthropology, and sociology, Dorais integrates these diverse perspectives in a comprehensive view of native language development, maintenance, and use under conditions of marginalization due to social transition.

Abstract

Infants parse speech into word-sized units according to biases that develop in the first year. One bias, present before the age of 7 months, is to cluster syllables that tend to co-occur. The present computational research demonstrates that this statistical clustering bias could lead to the extraction of speech sequences that are actual words, rather than missegmentations. In English and Dutch, these word-forms exhibit the strong–weak (trochaic) pattern that guides lexical segmentation after 8 months, suggesting that the trochaic parsing bias is learned as a generalization from statistically extracted bisyllables, and not via attention to short utterances or to high-frequency bisyllables. Extracted word-forms come from various syntactic classes, and exhibit distributional characteristics enabling rudimentary sorting of words into syntactic categories. The results highlight the importance of infants’ first year in language learning: though they may know the meanings of very few words, infants are well on their way to building a vocabulary.

Abstract

During the first year of life, infants' perception of speech becomes tuned to the phonology of the native language, as revealed in laboratory discrimination and categorization tasks using syllable stimuli. However, the implications of these results for the development of the early vocabulary remain controversial, with some results suggesting that infants retain only vague, sketchy phonological representations of words. Five experiments using a preferential listening procedure tested Dutch 11-month-olds' responses to word, nonword and mispronounced-word stimuli. Infants listened longer to words than nonwords, but did not exhibit this response when words were mispronounced at onset or at offset. In addition, infants preferred correct pronunciations to onset mispronunciations. The results suggest that infants' encoding of familiar words includes substantial phonological detail.

Abstract

Two experiments examined the nature of access, storage, and comprehension of idiomatic phrases. In both studies a Phrase Classification Task was utilized. In this, reaction times to determine whether or not word strings constituted acceptable English phrases were measured. Classification times were significantly faster to idiom than to matched control phrases. This effect held under conditions involving different categories of idioms, different transitional probabilities among words in the phrases, and different levels of awareness of the presence of idioms in the materials. The data support a Lexical Representation Hypothesis for the processing of idioms.

Abstract

To investigate the neural underpinnings of word decoding, and how it changes as a function of repeated exposure, we trained Dutch participants repeatedly over the course of a month of training to articulate a set of novel disyllabic input strings written in Greek script to avoid the use of familiar orthographic representations. The syllables in the input were phonotactically legal combinations but non-existent in the Dutch language, allowing us to assess their role in novel word decoding. Not only trained disyllabic pseudowords were tested but also pseudowords with recombined patterns of syllables to uncover the emergence of syllabic representations. We showed that with extensive training, articulation became faster and more accurate for the trained pseudowords. On the neural level, the initial stage of decoding was reflected by increased activity in visual attention areas of occipito-temporal and occipito-parietal cortices, and in motor coordination areas of the precentral gyrus and the inferior frontal gyrus. After one month of training, memory representations for holistic information (whole word unit) were established in areas encompassing the angular gyrus, the precuneus and the middle temporal gyrus. Syllabic representations also emerged through repeated training of disyllabic pseudowords, such that reading recombined syllables of the trained pseudowords showed similar brain activation to trained pseudowords and were articulated faster than novel combinations of letter strings used in the trained pseudowords.

Abstract

The complementary learning systems account of declarative memory suggests two distinct memory networks, a fast-mapping, episodic system involving the hippocampus, and a slower semantic memory system distributed across the neocortex in which new information is gradually integrated with existing representations. In this study, we investigated the extent to which these two networks are involved in the integration of novel words into the lexicon after extensive learning, and how the involvement of these networks changes after 24 hours. In particular, we explored whether having richer information at encoding influences the lexicalization trajectory. We trained participants with two sets of novel words, one where exposure was only to the words’ phonological forms (the form-only condition), and one where pictures of unfamiliar objects were associated with the words’ phonological forms (the picture-associated condition). A behavioral measure of lexical competition (indexing lexicalization) indicated stronger competition effects for the form-only words. Imaging (fMRI) results revealed greater involvement of phonological lexical processing areas immediately after training in the form-only condition, suggesting tight connections were formed between novel words and existing lexical entries already at encoding. Retrieval of picture-associated novel words involved the episodic/hippocampal memory system more extensively. Although lexicalization was weaker in the picture-associated condition, overall memory strength was greater when tested after a 24 hours’ delay, probably due to the availability of both episodic and lexical memory networks to aid retrieval. It appears that, during lexicalization of a novel word, the relative involvement of different memory networks differs according to the richness of the information about that word available at encoding.

Abstract

Not unlike the tonal system in Chinese, Japanese habitually attaches pitch accents to the production of words. However, in contrast to Chinese, few homophonic word-pairs are really distinguished by pitch accents (Shibata & Shibata, 1990). This predicts that pitch accent plays a small role in lexical selection for Japanese language comprehension. The present study investigated whether native Japanese speakers necessarily use pitch accent in the processing of accent-contrasted homophonic pairs (e.g., ame [LH] for 'candy' and ame [HI] for 'rain') measuring electroencephalographic (EEG) potentials. Electrophysiological evidence (i.e., N400) was obtained when a word was semantically incorrect for a given context but not for incorrectly accented homophones. This suggests that pitch accent indeed plays a minor role when understanding Japanese. (C) 2013 Elsevier Ltd. All rights reserved.

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

Attraction interference in language comprehension and production may be as a result of common or different processes. In the present paper, we investigate attraction interference during language comprehension, focusing on the contexts in which interference arises and the time-course of these effects. Using evidence from event-related brain potentials (ERPs) and sentence judgment times, we show that agreement attraction in comprehension is best explained as morphosyntactic interference during memory retrieval. This stands in contrast to attraction as a message-level process involving the representation of the subject NP's number features, which is a strong contributor to attraction in production. We thus argue that the cognitive antecedents of agreement attraction in comprehension are non-identical with those of attraction in production, and moreover, that attraction in comprehension is primarily a consequence of similarity-based interference in cue-based memory retrieval processes. We suggest that mechanisms responsible for attraction during language comprehension are a subset of those involved in language production.

Abstract

The rates of overspecification of color, pattern, and size are compared, to investigate how salience and absoluteness contribute to the production of overspecification. Color and pattern are absolute and salient attributes, whereas size is relative and less salient. Additionally, a tendency toward consistent responses is assessed. Using a within-participants design, we find similar rates of color and pattern overspecification, which are both higher than the rate of size overspecification. Using a between-participants design, however, we find similar rates of pattern and size overspecification, which are both lower than the rate of color overspecification. This indicates that although many speakers are more likely to include color than pattern (probably because color is more salient), they may also treat pattern like color due to a tendency toward consistency. We find no increase in size overspecification when the salience of size is increased, suggesting that speakers are more likely to include absolute than relative attributes. However, we do find an increase in size overspecification when mentioning the attributes is triggered, which again shows that speakers tend to refer in a consistent manner, and that there are circumstances in which even size overspecification is frequently produced.

Abstract

Although visual imagery is argued to be an essential component of autobiographical memory, there have been surprisingly few studies on autobiographical memory processes in blind individuals, who have had no or limited visual input. The purpose of the present study was to investigate how blindness affects retrieval and phenomenology of autobiographical memories. We asked 48 congenital/early blind and 48 sighted participants to recall autobiographical memories in response to six cue words, and to fill out the Autobiographical Memory Questionnaire measuring a number of variables including imagery, belief and recollective experience associated with each memory. Blind participants retrieved fewer memories and reported higher auditory imagery at retrieval than sighted participants. Moreover, within the blind group, participants with total blindness reported higher auditory imagery than those with some light perception. Blind participants also assigned higher importance, belief and recollection ratings to their memories than sighted participants. Importantly, these group differences remained the same for recent as well as childhood memories.

Abstract

Temporal cues can be used to selectively attend to relevant information during abundant sensory stimulation. However, such cues differ vastly in the accuracy of their temporal estimates, ranging from very predictable to very unpredictable. When cues are strongly predictable, attention may facilitate selective processing by aligning relevant incoming information to high neuronal excitability phases of ongoing low-frequency oscillations. However, top-down effects on ongoing oscillations when temporal cues have some predictability, but also contain temporal uncertainties, are unknown. Here, we experimentally created such a situation of mixed predictability and uncertainty: A target could occur within a limited time window after cue but was always unpredictable in exact timing. Crucially to assess top-down effects in such a mixed situation, we manipulated target probability. High target likelihood, compared with low likelihood, enhanced delta oscillations more strongly as measured by evoked power and intertrial coherence. Moreover, delta phase modulated detection rates for probable targets. The delta frequency range corresponds with half-a-period to the target occurrence window and therefore suggests that low-frequency phase reset is engaged to produce a long window of high excitability when event timing is uncertain within a restricted temporal window.

Abstract

The role of oscillatory phase for perceptual and cognitive processes is being increasingly acknowledged. To date, little is known about the direct role of phase in categorical perception. Here we show in two separate experiments that the identification of ambiguous syllables that can either be perceived as / da/ or / ga/ is biased by the underlying oscillatory phase as measured with EEG and sensory entrainment to rhythmic stimuli. The measured phase difference in which perception is biased toward / da/ or / ga/ exactly matched the different temporal onset delays in natural audiovisual speech between mouth movements and speech sounds, which last 80 ms longer for / ga/ than for / da/. These results indicate the functional relationship between prestimulus phase and syllable identification, and signify that the origin of this phase relationship could lie in exposure and subsequent learning of unique audiovisual temporal onset differences.

Abstract

Temporal structure in the environment often has predictive value for anticipating the occurrence of forthcoming events. In this study we investigated the influence of two types of predictive temporal information on the perception of near-threshold auditory stimuli: 1) intrinsic temporal rhythmicity within an auditory stimulus stream and 2) temporally-predictive visual cues. We hypothesized that combining predictive temporal information within- and across-modality should decrease the threshold at which sounds are detected, beyond the advantage provided by each information source alone. Two experiments were conducted in which participants had to detect tones in noise. Tones were presented in either rhythmic or random sequences and were preceded by a temporally predictive visual signal in half of the trials. We show that detection intensities are lower for rhythmic (vs. random) and audiovisual (vs. auditory-only) presentation, independent from response bias, and that this effect is even greater for rhythmic audiovisual presentation. These results suggest that both types of temporal information are used to optimally process sounds that occur at expected points in time (resulting in enhanced detection), and that multiple temporal cues are combined to improve temporal estimates. Our findings underscore the flexibility and proactivity of the perceptual system which uses within- and across-modality temporal cues to anticipate upcoming events and process them optimally. (C) 2014 Elsevier Ltd. All rights reserved.

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

Gesture is an important precursor of children’s early language development, for example, in the transition to multiword speech and as a predictor of later language abilities. However, it is unclear whether gestural input can influence children’s comprehension of complex grammatical constructions. In Study 1, 3- (M = 3 years 5 months) and 4-year-old (M = 4 years 6 months) children witnessed 2-participant actions described using the infrequent object-cleft-construction (OCC; It was the dog that the cat chased). Half saw an experimenter accompanying her descriptions with gestures representing the 2 participants and indicating the direction of action; the remaining children did not witness gesture. Children who witnessed gestures showed better comprehension of the OCC than those who did not witness gestures, both in and beyond the immediate physical context, but this benefit was restricted to the oldest 4-year-olds. In Study 2, a further group of older 4-year-old children (M = 4 years 7 months) witnessed the same 2-participant actions described by an experimenter and accompanied by gestures, but the gesture represented only the 2 participants and not the direction of the action. Again, a benefit of gesture was observed on subsequent comprehension of the OCC. We interpret these findings as demonstrating that representational cospeech gestures can help children comprehend complex linguistic structures by highlighting the roles played by the participants in the event.

Abstract

This study examined patterns of auxiliary provision and omission for the auxiliaries BE and HAVE in a longitudinal data set from 11 children between the ages of two and three years. Four possible explanations for auxiliary omission—a lack of lexical knowledge, performance limitations in production, the Optional Infinitive hypothesis, and patterns of auxiliary use in the input—were examined. The data suggest that although none of these accounts provides a full explanation for the pattern of auxiliary use and nonuse observed in children's early speech, integrating input-based and lexical learning-based accounts of early language acquisition within a constructivist approach appears to provide a possible framework in which to understand the patterns of auxiliary use found in the children's speech. The implications of these findings for models of children's early language acquisition 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

To test the hypothesis that thalamic midline nuclei play a transient role in memory consolidation, we reanalyzed a prospective functional MRI study, contrasting recent and progressively more remote memory retrieval. We revealed a transient thalamic connectivity increase with the hippocampus, the medial prefrontal cortex (mPFC), and a parahippocampal area, which decreased with time. In turn, mPFC-parahippocampal connectivity increased progressively. These findings support a model in which thalamic midline nuclei serve as a hub linking hippocampus, mPFC, and posterior representational areas during memory retrieval at an early (2 h) stage of consolidation, extending classical systems consolidation models by attributing a transient role to midline thalamic nuclei.

Abstract

The Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Consortium is a collaborative network of researchers working together on a range of large-scale studies that integrate data from 70 institutions worldwide. Organized into Working Groups that tackle questions in neuroscience, genetics, and medicine, ENIGMA studies have analyzed neuroimaging data from over 12,826 subjects. In addition, data from 12,171 individuals were provided by the CHARGE consortium for replication of findings, in a total of 24,997 subjects. By meta-analyzing results from many sites, ENIGMA has detected factors that affect the brain that no individual site could detect on its own, and that require larger numbers of subjects than any individual neuroimaging study has currently collected. ENIGMA’s first project was a genome-wide association study identifying common variants in the genome associated with hippocampal volume or intracranial volume. Continuing work is exploring genetic associations with subcortical volumes (ENIGMA2) and white matter microstructure (ENIGMA-DTI). Working groups also focus on understanding how schizophrenia, bipolar illness, major depression and attention deficit/hyperactivity disorder (ADHD) affect the brain. We review the current progress of the ENIGMA Consortium, along with challenges and unexpected discoveries made on the way

Abstract

Infants expect people to direct actions toward objects, and they respond to actions directed to themselves, but do they have expectations about actions directed to third parties? In two experiments, we used eye tracking to investigate 1- and 2-year-olds’ expectations about communicative actions addressed to a third party. Experiment 1 presented infants with videos where an adult (the Emitter) either uttered a sentence or produced non-speech sounds. The Emitter was either face-to-face with another adult (the Recipient) or the two were back-to-back. The Recipient did not respond to any of the sounds. We found that 2-, but not 1-year-olds looked quicker and longer at the Recipient following speech than non-speech, suggesting that they expected her to respond to speech. These effects were specific to the face-to-face context. Experiment 2 presented 1-year-olds with similar face-to-face exchanges but modified to engage infants and minimize task demands. The infants looked quicker to the Recipient following speech than non-speech, suggesting that they expected a response to speech. The study suggests that by 1 year of age infants expect communicative actions to be directed at a third-party listener.

Abstract

We investigated 14-month-old infants’ expectations toward a third party addressee of communicative gestures and an instrumental action. Infants’ eye movements were tracked as they observed a person (the Gesturer) point, direct a palm-up request gesture, or reach toward an object, and another person (the Addressee) respond by grasping it. Infants’ looking patterns indicate that when the Gesturer pointed or used the palm-up request, infants anticipated that the Addressee would give the object to the Gesturer, suggesting that they ascribed a motive of request to the gestures. In contrast, when the Gesturer reached for the object, and in a control condition where no action took place, the infants did not anticipate the Addressee’s response. The results demonstrate that infants’ recognition of communicative gestures extends to others’ interactions, and that infants can anticipate how third-party addressees will respond to others’ gestures.

Abstract

Germline mutations in PTEN, which encodes a widely expressed phosphatase, was mapped to 10q23 and identified as the susceptibility gene for Cowden syndrome, characterized by macrocephaly and high risks of breast, thyroid, and other cancers. The phenotypic spectrum of PTEN mutations expanded to include autism with macrocephaly only 10 years ago. Neurological studies of patients with PTEN-associated autism spectrum disorder (ASD) show increases in cortical white matter and a distinctive cognitive profile, including delayed language development with poor working memory and processing speed. Once a germline PTEN mutation is found, and a diagnosis of phosphatase and tensin homolog (PTEN) hamartoma tumor syndrome made, the clinical outlook broadens to include higher lifetime risks for multiple cancers, beginning in childhood with thyroid cancer. First described as a tumor suppressor, PTEN is a major negative regulator of the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (mTOR) signaling pathway—controlling growth, protein synthesis, and proliferation. This canonical function combines with less well-understood mechanisms to influence synaptic plasticity and neuronal cytoarchitecture. Several excellent mouse models of Pten loss or dysfunction link these neural functions to autism-like behavioral abnormalities, such as altered sociability, repetitive behaviors, and phenotypes like anxiety that are often associated with ASD in humans. These models also show the promise of mTOR inhibitors as therapeutic agents capable of reversing phenotypes ranging from overgrowth to low social behavior. Based on these findings, therapeutic options for patients with PTEN hamartoma tumor syndrome and ASD are coming into view, even as new discoveries in PTEN biology add complexity to our understanding of this master regulator.

Abstract

PTEN Hamartoma Tumor Syndrome (PHTS) is an autosomal-dominant genetic condition underlying a subset of autism spectrum disorder (ASD) with macrocephaly. Caused by germline mutations in PTEN, PHTS also causes increased risks of multiple cancers via dysregulation of the PI3K and MAPK signaling pathways. Conditional knockout models have shown that neural Pten regulates social behavior, proliferation and cell size. Although much is known about how the intracellular localization of PTEN regulates signaling in cancer cell lines, we know little of how PTEN localization influences normal brain physiology and behavior. To address this, we generated a germline knock-in mouse model of cytoplasm-predominant Pten and characterized its behavioral and cellular phenotypes. The homozygous Ptenm3m4 mice have decreased total Pten levels including a specific drop in nuclear Pten and exhibit region-specific increases in brain weight. The Ptenm3m4 model displays sex-specific increases in social motivation, poor balance and normal recognition memory—a profile reminiscent of some individuals with high functioning ASD. The cytoplasm-predominant protein caused cellular hypertrophy limited to the soma and led to increased NG2 cell proliferation and accumulation of glia. The animals also exhibit significant astrogliosis and microglial activation, indicating a neuroinflammatory phenotype. At the signaling level, Ptenm3m4 mice show brain region-specific differences in Akt activation. These results demonstrate that differing alterations to the same autism-linked gene can cause distinct behavioral profiles. The Ptenm3m4 model is the first murine model of inappropriately elevated social motivation in the context of normal cognition and may expand the range of autism-related behaviors replicated in animal models.

Abstract

The neural response to a stimulus is influenced by endogenous factors such as expectation and attention. Current research suggests that expectation and attention exert their effects in opposite directions, where expectation decreases neural activity in sensory areas, while attention increases it. However, expectation and attention are usually studied either in isolation or confounded with each other. A recent study suggests that expectation and attention may act jointly on sensory processing, by increasing the neural response to expected events when they are attended, but decreasing it when they are unattended. Here we test this hypothesis in an auditory temporal cueing paradigm using magnetoencephalography in humans. In our study participants attended to, or away from, tones that could arrive at expected or unexpected moments. We found a decrease in auditory beta band synchrony to expected (versus unexpected) tones if they were unattended, but no difference if they were attended. Modulations in beta power were already evident prior to the expected onset times of the tones. These findings suggest that expectation and attention jointly modulate sensory processing.

Abstract

In 3 experiments, we investigated whether intonational phrase structure can be primed. In all experiments, participants listened to sentences in which the presence and location of intonational phrase boundaries were manipulated such that the recording included either no intonational phrase boundaries, a boundary in a structurally dispreferred location, a boundary in a preferred location, or boundaries in both locations. In Experiment 1, participants repeated the sentences to test whether they would reproduce the prosodic structure they had just heard. Experiments 2 and 3 used a prime–target paradigm to evaluate whether the intonational phrase structure heard in the prime sentence might influence that of a novel target sentence. Experiment 1 showed that participants did repeat back sentences that they had just heard with the original intonational phrase structure, yet Experiments 2 and 3 found that exposure to intonational phrase boundaries on prime trials did not influence how a novel target sentence was prosodically phrased. These results suggest that speakers may retain the intonational phrasing of a sentence, but this effect is not long-lived and does not generalize across unrelated sentences. Furthermore, these findings provide no evidence that intonational phrase structure is formulated during a planning stage that is separate from other sources of linguistic information.

Abstract

In this study, we investigate the timing of pre-answer inbreaths in order to shed light on the time course of response planning and execution in conversational turn-taking. Using acoustic and inductive plethysmography recordings of seven dyadic conversations in Dutch, we show that pre-answer inbreaths in conversation typically begin briefly after the end of questions. We also show that the presence of a pre-answer inbreath usually co-occurs with substantially delayed answers, with a modal latency of 576 ms vs. 100 ms for answers not preceded by an inbreath. Based on previously reported minimal latencies for internal intercostal activation and the production of speech sounds, we propose that vocal responses, either in the form of a pre-utterance inbreath or of speech proper when an inbreath is not produced, are typically launched in reaction to information present in the last portion of the interlocutor’s turn. We also show that short responses are usually made on residual breath, while longer responses are more often preceded by an inbreath. This relation of inbreaths to answer length suggests that by the time an inbreath is launched, typically during the last few hundred milliseconds of the question, the length of the answer is often prepared to some extent. Together, our findings are consistent with a two-stage model of response planning in conversational turn-taking: early planning of content often carried out in overlap with the incoming turn, and late launching of articulation based on the identification of turn-final cues

Abstract

We investigate the extent to which French polar questions and continuation statements, two types of utterances with similar morphosyntactic and intonational forms but different pragmatic functions, can be distinguished in conversational data based on phonetic and visual bodily information. We show that the two utterance types can be distinguished well over chance level by automatic classification models including several phonetic and visual cues. We also show that a considerable amount of relevant phonetic and visual information is present before the last portion of the utterances, potentially assisting early speech act recognition by addressees. These findings indicate that bottom-up phonetic and visual cues may play an important role during the production and recognition of speech acts alongside top-down contextual information.

Abstract

Neuregulin 1 (NRG1) and v-erb-a erythroblastic leukemia viral oncogene homolog 4 (ErbB4) have been extensively studied in schizophrenia susceptibility because of their pivotal role in key neurodevelopmental processes. One of the reasons for the inconsistencies in results could be the fact that the phenotype investigated has mostly the diagnosis of schizophrenia per se, which is widely heterogeneous, both clinically and biologically. In the present study we tested, in a large cohort of 461 schizophrenia patients recruited in Scotland, whether several SNPs in NRG1 and/or ErbB4 are associated with schizophrenia symptom dimensions as evaluated by the Positive and Negative Syndrome Scale (PANSS). We then followed up nominally significant results in a second cohort of 439 schizophrenia subjects recruited in Germany. Using linear regression, we observed two different groups of polymorphisms in NRG1 gene: one showing a nominal association with higher scores of the PANSS positive dimension and the other one with higher scores of the PANSS negative dimension. Regarding ErbB4, a small cluster located in the 5' end of the gene was detected, showing nominal association mainly with negative, general and total dimensions of the PANSS. These findings suggest that some regions of NRG1 and ErbB4 are functionally involved in biological processes that underlie some of the phenotypic manifestations of schizophrenia. Because of the lack of significant association after correction for multiple testing, our analyses should be considered as exploratory and hypothesis generating for future studies.

Abstract

Purpose: To determine clinical phenotypes, evolution and genetic background of a large family with a combination of two unusual forms of reflex epilepsies. Method: Phenotyping was performed in eighteen family members (10 F, 8 M) including standardized EEG recordings with intermittent photic stimulation (IPS). Genetic analyses (linkage scans, Whole Exome Sequencing (WES) and Functional studies) were performed using photoparoxysmal EEG responses (PPRs) as affection status. Results: The proband suffered from speaking induced jaw-jerks and increasing limb jerks evoked by flickering sunlight since about 50 years of age. Three of her family members had the same phenotype. Generalized PPRs were found in seven members (six above 50 years of age) with myoclonus during the PPR. Evolution was typical: Sensitivity to lights with migraine-like complaints around adolescence, followed by jerks evoked by lights and spontaneously with dropping of objects, and strong increase of light sensitivity and onset of talking induced jaw jerks around 50 years. Linkage analysis showed suggestive evidence for linkage to four genomic regions. All photosensitive family members shared a heterozygous R129C mutation in the SCNM1 gene that regulates splicing of voltage gated ion channels. Mutation screening of 134 unrelated PPR patients and 95 healthy controls, did not replicate these findings. Conclusion: This family presents a combination of two rare reflex epilepsies. Genetic analysis favors four genomic regions and points to a shared SCNM1 mutation that was not replicated in a general cohort of photosensitive subjects. Further genetic studies in families with similar combination of features are warranted. (C) 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Abstract

Objective: Patients with Parkinson's disease (PD) often suffer from impairments in executive functions, such as working memory deficits. It is widely held that dopamine depletion in the striatum contributes to these impairments through decreased activity and connectivity between task-related brain networks. We investigated this hypothesis by studying task-related network activity and connectivity within a sample of de novo patients with PD, versus healthy controls, during a visuospatial working memory task. Methods: Sixteen de novo PD patients and 35 matched healthy controls performed a visuospatial n-back task while we measured their behavioral performance and neural activity using functional magnetic resonance imaging. We constructed regions-of-interest in the bilateral inferior parietal cortex (IPC), bilateral dorsolateral prefrontal cortex (DLPFC), and bilateral caudate nucleus to investigate group differences in task-related activity. We studied network connectivity by assessing the functional connectivity of the bilateral DLPFC and by assessing effective connectivity within the frontoparietal and the frontostriatal networks. Results: PD patients, compared with controls, showed trend-significantly decreased task accuracy, significantly increased task-related activity in the left DLPFC and a trend-significant increase in activity of the right DLPFC, left caudate nucleus, and left IPC. Furthermore, we found reduced functional connectivity of the DLPFC with other task-related regions, such as the inferior and superior frontal gyri, in the PD group, and group differences in effective connectivity within the frontoparietal network. Interpretation: These findings suggest that the increase in working memory-related brain activity in PD patients is compensatory to maintain behavioral performance in the presence of network deficits. Hum Brain Mapp 36:1554-1566, 2015. (c) 2015 Wiley Periodicals, Inc.

Abstract

We present the concept of a community-augmented meta-analysis (CAMA), a simple yet novel tool that significantly facilitates the accumulation and evaluation of previous studies within a specific scientific field. A CAMA is a combination of a meta-analysis and an open repository. Like a meta-analysis, it is centered around a psychologically relevant topic and includes methodological details and standardized effect sizes. As in a repository, data do not remain undisclosed and static after publication but can be used and extended by the research community, as anyone can download all information and can add new data via simple forms. Based on our experiences with building three CAMAs, we illustrate the concept and explain how CAMAs can facilitate improving our research practices via the integration of past research, the accumulation of knowledge, and the documentation of file-drawer studies

Abstract

Numerous studies have revealed an asymmetry tied to the perception of coronal place of articulation: participants accept a labial mispronunciation of a coronal target, but not vice versa. Whether or not this asymmetry is based on language-general properties or arises from language-specific experience has been a matter of debate. The current study suggests a bias of the first type by documenting an early, cross-linguistic asymmetry related to coronal place of articulation. Japanese and Dutch 4- and 6-month-old infants showed evidence of discrimination if they were habituated to a labial and then tested on a coronal sequence, but not vice versa. This finding has important implications for both phonological theories and infant speech perception research

Abstract

Although the majority of evidence on perceptual narrowing in speech sounds is based on consonants, most models of infant speech perception generalize these findings to vowels, assuming that vowel perception improves for vowel sounds that are present in the infant's native language within the first year of life, and deteriorates for non-native vowel sounds over the same period of time. The present meta-analysis contributes to assessing to what extent these descriptions are accurate in the first comprehensive quantitative meta-analysis of perceptual narrowing in infant vowel discrimination, including results from behavioral, electrophysiological, and neuroimaging methods applied to infants 0–14 months of age. An analysis of effect sizes for native and non-native vowel discrimination over the first year of life revealed that they changed with age in opposite directions, being significant by about 6 months of age

Abstract

Japanese infant-directed speech (IDS) and adult-directed speech (ADS) were compared on their segmental distributions and consonant-vowel association patterns. Consistent with findings in other languages, a higher ratio of segments that are generally produced early was found in IDS compared to ADS: more labial consonants and low-central vowels, but fewer fricatives. Consonant-vowel associations also favored the early-produced labial-central, coronal-front, coronal-central, and dorsal-back patterns. On the other hand, clear language-specific patterns included a higher frequency of dorsals, affricates, geminates and moraic nasals in IDS. These segments are frequent in adult Japanese, but not in the early productions or the IDS of other studied languages. In combination with previous results, the current study suggests that both fine-tuning (an increased use of early-produced segments) and highlighting (an increased use of language-specifically relevant segments) might modify IDS on segmental level.

Abstract

Listeners resolve ambiguity in speech by consulting context. Extensive research on this issue has largely relied on continua of sounds constructed to vary incrementally between two phonemic endpoints. In this study we presented listeners instead with phonetic ambiguity of a kind with which they have natural experience: varying degrees of word-final /t/-reduction. In two experiments, Dutch listeners decided whether or not the verb in a sentence such as Maar zij ren(t) soms ‘But she sometimes run(s)’ ended in /t/. In Dutch, presence versus absence of final /t/ distinguishes third- from first-person singular present-tense verbs. Acoustic evidence for /t/ varied from clear to absent, and immediately preceding phonetic context was consistent with more versus less likely deletion of /t/. In both experiments, listeners reported more /t/s in sentences in which /t/ would be syntactically correct. In Experiment 1, the disambiguating syntactic information preceded the target verb, as above, while in Experiment 2, it followed the verb. The syntactic bias was greater for fast than for slow responses in Experiment 1, but no such difference appeared in Experiment 2. We conclude that syntactic information does not directly influence pre-lexical processing, but is called upon in making phoneme decisions.

Abstract

This study compares how Dutch and German, two closely related languages, signal a shift from a negative to a positive polarity in two contexts, when contrasting the polarity relative to a different topic situation (In my picture the man washes the car following after In my picture the man does not wash the car, henceforth polarity contrast) and when correcting the polarity of a proposition (The man washes the car following after The man does not wash the car, henceforth polarity correction). Production data show that in both contexts German speakers produced Verum focus (i.e., a high-falling pitch accent on the finite verb), while Dutch speakers mostly used the accented affirmative particle wel. This shows that even lexically and syntactically close languages behave differently when it comes to signalling certain pragmatic functions. Furthermore, we found that in polarity correction contexts, both affirmative particles and Verum focus were realized with stronger prosodic prominence. This difference was found in both languages and might be due to a secondary (syntagmatic) effect of the information structure of the utterance (absence or presence of a contrastive topic).

Abstract

There is increasing evidence that long-lasting morphologic and
functional consequences can be present in the human visual system
after repetitive mild traumatic brain injury (r-mTBI). The exact lo-
cation and extent of the damage in this condition are not well un-
derstood. Using a recently developed mouse model of r-mTBI, we
assessed the effects on the retina and optic nerve using histology and
immunohistochemistry, electroretinography (ERG), and spectral-
domain optical coherence tomography (SD-OCT) at 10 and 13 weeks
after injury. Control mice received repetitive anesthesia alone (r-sham).
We observed decreased optic nerve diameters and increased cellularity
and areas of demyelination in optic nerves in r-mTBI versus r-sham
mice. There were concomitant areas of decreased cellularity in the
retinal ganglion cell layer and approximately 67% decrease in brain-
specific homeobox/POU domain protein 3AYpositive retinal ganglion
cells in retinal flat mounts. Furthermore, SD-OCT demonstrated a de-
tectable thinning of the inner retina; ERG demonstrated a decrease in
the amplitude of the photopic negative response without any change in
a- or b-wave amplitude or timing. Thus, the ERG and SD-OCT data
correlated well with changes detected by morphometric, histologic,
and immunohistochemical methods, thereby supporting the use of
these noninvasive methods in the assessment of visual function and
morphology in clinical cases of mTBI.

Abstract

The contribution of rare and low-frequency variants to human traits is largely unexplored. Here we describe insights from sequencing whole genomes (low read depth, 7×) or exomes (high read depth, 80×) of nearly 10,000 individuals from population-based and disease collections. In extensively phenotyped cohorts we characterize over 24 million novel sequence variants, generate a highly accurate imputation reference panel and identify novel alleles associated with levels of triglycerides (APOB), adiponectin (ADIPOQ) and low-density lipoprotein cholesterol (LDLR and RGAG1) from single-marker and rare variant aggregation tests. We describe population structure and functional annotation of rare and low-frequency variants, use the data to estimate the benefits of sequencing for association studies, and summarize lessons from disease-specific collections. Finally, we make available an extensive resource, including individual-level genetic and phenotypic data and web-based tools to facilitate the exploration of association results.

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

Abstract

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

Abstract

Common genetic variants have been identified for adult height, but not much is known about the genetics of skeletal growth in early life. To identify common genetic variants that influence fetal skeletal growth, we meta-analyzed 22 genome-wide association studies (Stage 1; N = 28 459). We identified seven independent top single nucleotide polymorphisms (SNPs) (P < 1 × 10(-6)) for birth length, of which three were novel and four were in or near loci known to be associated with adult height (LCORL, PTCH1, GPR126 and HMGA2). The three novel SNPs were followed-up in nine replication studies (Stage 2; N = 11 995), with rs905938 in DC-STAMP domain containing 2 (DCST2) genome-wide significantly associated with birth length in a joint analysis (Stages 1 + 2; β = 0.046, SE = 0.008, P = 2.46 × 10(-8), explained variance = 0.05%). Rs905938 was also associated with infant length (N = 28 228; P = 5.54 × 10(-4)) and adult height (N = 127 513; P = 1.45 × 10(-5)). DCST2 is a DC-STAMP-like protein family member and DC-STAMP is an osteoclast cell-fusion regulator. Polygenic scores based on 180 SNPs previously associated with human adult stature explained 0.13% of variance in birth length. The same SNPs explained 2.95% of the variance of infant length. Of the 180 known adult height loci, 11 were genome-wide significantly associated with infant length (SF3B4, LCORL, SPAG17, C6orf173, PTCH1, GDF5, ZNFX1, HHIP, ACAN, HLA locus and HMGA2). This study highlights that common variation in DCST2 influences variation in early growth and adult height.

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

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