Publications

Abstract

Importance 
Neuroticism is a pervasive risk factor for psychiatric conditions. It genetically overlaps with major depressive disorder (MDD) and is therefore an important phenotype for psychiatric genetics. The Genetics of Personality Consortium has created a resource for genome-wide association analyses of personality traits in more than 63 000 participants (including MDD cases).Objectives
To identify genetic variants associated with neuroticism by performing a meta-analysis of genome-wide association results based on 1000 Genomes imputation; to evaluate whether common genetic variants as assessed by single-nucleotide polymorphisms (SNPs) explain variation in neuroticism by estimating SNP-based heritability; and to examine whether SNPs that predict neuroticism also predict MDD.Design, Setting, and Participants
Genome-wide association meta-analysis of 30 cohorts with genome-wide genotype, personality, and MDD data from the Genetics of Personality Consortium. The study included 63 661 participants from 29 discovery cohorts and 9786 participants from a replication cohort. Participants came from Europe, the United States, or Australia. Analyses were conducted between 2012 and 2014.Main Outcomes and Measures
Neuroticism scores harmonized across all 29 discovery cohorts by item response theory analysis, and clinical MDD case-control status in 2 of the cohorts.Results
A genome-wide significant SNP was found on 3p14 in MAGI1 (rs35855737; P = 9.26 × 10−9 in the discovery meta-analysis). This association was not replicated (P = .32), but the SNP was still genome-wide significant in the meta-analysis of all 30 cohorts (P = 2.38 × 10−8). Common genetic variants explain 15% of the variance in neuroticism. Polygenic scores based on the meta-analysis of neuroticism in 27 cohorts significantly predicted neuroticism (1.09 × 10−12 <} P {<} .05) and MDD (4.02 × 10−9 {<} P {< .05) in the 2 other cohorts.Conclusions and Relevance
This study identifies a novel locus for neuroticism. The variant is located in a known gene that has been associated with bipolar disorder and schizophrenia in previous studies. In addition, the study shows that neuroticism is influenced by many genetic variants of small effect that are either common or tagged by common variants. These genetic variants also influence MDD. Future studies should confirm the role of the MAGI1 locus for neuroticism and further investigate the association of MAGI1 and the polygenic association to a range of other psychiatric disorders that are phenotypically correlated with neuroticism.

Abstract

This article presents information about two so far undescribed buildings made by the Trobriand Islanders, the bomiyoyeva and the bomduvadova. These structures are connected to the highest-ranking chiefs living in Labai and Omarakana on Kiriwina Island. They highlight the power and eminence of these chiefs. After a brief report on the history of this project, the structure of the two houses, their function, and their use is described and information on their construction and their mythical background is provided. Finally, everyday as well as ritual, social, and political functions of both buildings are discussed. [Melanesia, Trobriand Islands, Tabalu chiefs, yams houses, bomiyoyeva, bomduvadova, authoritative capacities]

Abstract

The acquisition of linguistic structures that require perspective-taking at the level of message generation is challenging. We investigate use of progressive aspect in L2 event encoding, using a sentence priming paradigm. We focus on Dutch, in which use of progressive aspect is optional. The progressive consists of a prepositional phrase (‘aan het,’ at-the), plus a verbal infinitive. We ask, to what extent L2 speakers, in comparison to native speakers, show priming effects in relation to form (prepositional phrase) or conceptual (progressive aspect) prime sentences. In native Dutch speakers we find a priming effect for the ‘progressive prime,’ compared to a ‘neutral prime’ (aspectually neutral event description). In L2 speakers this effect was absent. For the form prime, no priming effects were obtained in native speakers, rather, we find evidence for a partial blocking effect in L2 speakers. Results suggest that the strength of the link between concept and form of progressive aspect differs in native and L2 speakers. Specific factors contributed to the L2 findings, e.g., level of L2 proficiency and degree of L2 exposure. We conclude that (1) the conceptual basis of grammatical aspect can be primed in native speakers, and (2) in L2 speakers, access to conceptual information is less automatized.

Abstract

Gricean pragmatics has often been criticised for being implausible from a psychological point of view. This line of criticism is never backed up by empirical evidence, but more importantly, it ignores the fact that Grice never meant to advance a processing theory, in the first place. Taking our lead from Marr (1982), we distinguish between two levels of explanation: at the W-level, we are concerned with what agents do and why; at the H-level, we ask how agents do whatever it is they do. Whereas pragmatics is pitched at the W-level, processing theories are at the H-level. This is not to say that pragmatics has no implications for psychology at all, but it is to say that its implications are less direct than is often supposed.

Abstract

A key function of attention is to select an appropriate subset of available information by facilitation of attended processes and/or inhibition of irrelevant processing. Functional imaging studies, using positron emission tomography, have during different experimental tasks revealed decreased neuronal activity in areas that process input from unattended sensory modalities. It has been hypothesized that these decreases reflect a selective inhibitory modulation of nonrelevant cortical processing. In this study we addressed this question using a continuous arithmetical task with and without concomitant disturbing auditory input (task-irrelevant speech). During the arithmetical task, irrelevant speech did not affect task-performance but yielded decreased activity in the auditory and midcingulate cortices and increased activity in the left posterior parietal cortex. This pattern of modulation is consistent with a top down inhibitory modulation of a nonattended input to the auditory cortex and a coexisting, attention-based facilitation of taskrelevant processing in higher order cortices. These findings suggest that task-related decreases in cortical activity may be of functional importance in the understanding of both attentional mechanisms and taskrelated information processing.

Abstract

Reading and language abilities are heritable traits that are likely to share some genetic influences with each other. To identify pleiotropic genetic variants affecting these traits, we first performed a Genome-wide Association Scan (GWAS) meta-analysis using three richly characterised datasets comprising individuals with histories of reading or language problems, and their siblings. GWAS was performed in a total of 1862 participants using the first principal component computed from several quantitative measures of reading- and language-related abilities, both before and after adjustment for performance IQ. We identified novel suggestive associations at the SNPs rs59197085 and rs5995177 (uncorrected p≈10−7 for each SNP), located respectively at the CCDC136/FLNC and RBFOX2 genes. Each of these SNPs then showed evidence for effects across multiple reading and language traits in univariate association testing against the individual traits. FLNC encodes a structural protein involved in cytoskeleton remodelling, while RBFOX2 is an important regulator of alternative splicing in neurons. The CCDC136/FLNC locus showed association with a comparable reading/language measure in an independent sample of 6434 participants from the general population, although involving distinct alleles of the associated SNP. Our datasets will form an important part of on-going international efforts to identify genes contributing to reading and language skills.

Abstract

In cochlear implants (CIs), acoustic speech cues, especially for pitch, are delivered in a degraded form. This study's aim is to assess whether due to degraded pitch cues, normal-hearing listeners and CI users employ different perceptual strategies to recognize vocal emotions, and, if so, how these differ. Voice actors were recorded pronouncing a nonce word in four different emotions: anger, sadness, joy, and relief. These recordings' pitch cues were phonetically analyzed. The recordings were used to test 20 normal-hearing listeners' and 20 CI users' emotion recognition. In congruence with previous studies, high-arousal emotions had a higher mean pitch, wider pitch range, and more dominant pitches than low-arousal emotions. Regarding pitch, speakers did not differentiate emotions based on valence but on arousal. Normal-hearing listeners outperformed CI users in emotion recognition, even when presented with CI simulated stimuli. However, only normal-hearing listeners recognized one particular actor's emotions worse than the other actors'. The groups behaved differently when presented with similar input, showing that they had to employ differing strategies. Considering the respective speaker's deviating pronunciation, it appears that for normal-hearing listeners, mean pitch is a more salient cue than pitch range, whereas CI users are biased toward pitch range cues

Abstract

Advances in molecular technologies make it possible to pinpoint genomic factors associated with complex human traits. For cognition and behaviour, identification of underlying genes provides new entry points for deciphering the key neurobiological pathways. In the past decade, the search for genetic correlates of musicality has gained traction. Reports have documented familial clustering for different extremes of ability, including amusia and absolute pitch (AP), with twin studies demonstrating high heritability for some music-related skills, such as pitch perception. Certain chromosomal regions have been linked to AP and musical aptitude, while individual candidate genes have been investigated in relation to aptitude and creativity. Most recently, researchers in this field started performing genome-wide association scans. Thus far, studies have been hampered by relatively small sample sizes and limitations in defining components of musicality, including an emphasis on skills that can only be assessed in trained musicians. With opportunities to administer standardized aptitude tests online, systematic large-scale assessment of musical abilities is now feasible, an important step towards high-powered genome-wide screens. Here, we offer a synthesis of existing literatures and outline concrete suggestions for the development of comprehensive operational tools for the analysis of musical phenotypes.

Abstract

The ability to recognize speech acts (verbal actions) in conversation is critical for everyday interaction. However, utterances are often underspecified for the speech act they perform, requiring listeners to rely on the context to recognize the action. The goal of this study was to investigate the time-course of auditory speech act recognition in action-underspecified utterances and explore how sequential context (the prior action) impacts this process. We hypothesized that speech acts are recognized early in the utterance to allow for quick transitions between turns in conversation. Event-related potentials (ERPs) were recorded while participants listened to spoken dialogues and performed an action categorization task. The dialogues contained target utterances that each of which could deliver three distinct speech acts depending on the prior turn. The targets were identical across conditions, but differed in the type of speech act performed and how it fit into the larger action sequence. The ERP results show an early effect of action type, reflected by frontal positivities as early as 200 ms after target utterance onset. This indicates that speech act recognition begins early in the turn when the utterance has only been partially processed. Providing further support for early speech act recognition, actions in highly constraining contexts did not elicit an ERP effect to the utterance-final word. We take this to show that listeners can recognize the action before the final word through predictions at the speech act level. However, additional processing based on the complete utterance is required in more complex actions, as reflected by a posterior negativity at the final word when the speech act is in a less constraining context and a new action sequence is initiated. These findings demonstrate that sentence comprehension in conversational contexts crucially involves recognition of verbal action which begins as soon as it can.

Abstract

Everyday conversation requires listeners to quickly recognize verbal actions, so-called speech acts, from the underspecified linguistic code and prepare a relevant response within the tight time constraints of turn-taking. The goal of this study was to determine the time-course of speech act recognition by investigating oscillatory EEG activity during comprehension of spoken dialogue. Participants listened to short, spoken dialogues with target utterances that delivered three distinct speech acts (Answers, Declinations, Pre-offers). The targets were identical across conditions at lexico-syntactic and phonetic/prosodic levels but differed in the pragmatic interpretation of the speech act performed. Speech act comprehension was associated with reduced power in the alpha/beta bands just prior to Declination speech acts, relative to Answers and Pre-offers. In addition, we observed reduced power in the theta band during the beginning of Declinations, relative to Answers. Based on the role of alpha and beta desynchronization in anticipatory processes, the results are taken to indicate that anticipation plays a role in speech act recognition. Anticipation of speech acts could be critical for efficient turn-taking, allowing interactants to quickly recognize speech acts and respond within the tight time frame characteristic of conversation. The results show that anticipatory processes can be triggered by the characteristics of the interaction, including the speech act type.

Abstract

The ability to repair problems with hearing or understanding in conversation is critical for successful communication. This article describes the linguistic practices of other-initiated repair (OIR) in Icelandic through quantitative and qualitative analysis of a corpus of video-recorded conversations. The study draws on the conceptual distinctions developed in the comparative project on repair described in the introduction to this issue. The main aim is to give an overview of the formats for OIR in Icelandic and the type of repair practices engendered by them. The use of repair initiations in social actions not aimed at solving comprehension problems is also briefly discussed. In particular, the interjection ha has a rich usage extending beyond open other-initiation of repair. By describing the linguistic machinery for other-initiated repair in Icelandic, this study contributes to the typology of conversational structure and to the still nascent field of Icelandic social interaction studies.

Abstract

Deaf children whose hearing losses prevent them from accessing spoken language and whose hearing parents have not exposed them to sign language develop gesture systems, called homesigns, which have many of the properties of natural language—the so-called resilient properties of language. We explored the resilience of structure built around the predicate—in particular, how manner and path are mapped onto the verb—in homesign systems developed by deaf children in Turkey and the United States. We also asked whether the Turkish homesigners exhibit sentence-level structures previously identified as resilient in American and Chinese homesigners. We found that the Turkish and American deaf children used not only the same production probability and ordering patterns to indicate who does what to whom, but also used the same segmentation and conflation patterns to package manner and path. The gestures that the hearing parents produced did not, for the most part, display the patterns found in the children's gestures. Although cospeech gesture may provide the building blocks for homesign, it does not provide the blueprint for these resilient properties of language.

Abstract

Vocal individuality provides a method of personalization for multiple avian species. However, expression of individual vocal features depends on necessity of recognition. Here we focused on chick vocalizations of demoiselle, Siberian and red-crowned cranes that differ by their body size, developmental rates and some ecological traits. Cranes are territorial during summer, but gather in
large flocks during autumn and winter. Nevertheless, parents keep feeding their chicks, even on winter grounds, despite the potential of confusing their own and alien
chicks. Here we aimed to compare expression of individuality and sex in calls of three crane species between solitary and gregarious periods of a chick’s life, and between species. We found significant individual patterns of
acoustic variables in the calls of all three species both before and after fledging. However, only red-crowned crane chicks increased expression of individuality significantly after the fledging. Also, we found that chicks of all three species significantly increased occurrence of nonlinear phenomena, i.e., irregular oscillations of soundproducing membranes (biphonations, sidebands, and deterministic chaos), in their calls after fledging. Non-linear phenomena can be a way of increasing the potential for
individual recognition as well as avoiding habituation of parents to their chicks’ calls. The older chicks are, the less
their parents feed them, and chicks benefit from keeping the permanent attention.

Abstract

Previous studies have described the existence of a phonotactic bias called the Labial–Coronal (LC) bias, corresponding to a tendency to produce more words beginning with a labial consonant followed by a coronal consonant (i.e. “bat”) than the opposite CL pattern (i.e. “tap”). This bias has initially been interpreted in terms of articulatory constraints of the human speech production system. However, more recently, it has been suggested that this presumably language-general LC bias in production might be accompanied by LC and CL biases in perception, acquired in infancy on the basis of the properties of the linguistic input. The present study investigates the origins of these perceptual biases, testing infants learning Japanese, a language that has been claimed to possess more CL than LC sequences, and comparing them with infants learning French, a language showing a clear LC bias in its lexicon. First, a corpus analysis of Japanese IDS and ADS revealed the existence of an overall LC bias, except for plosive sequences in ADS, which show a CL bias across counts. Second, speech preference experiments showed a perceptual preference for CL over LC plosive sequences (all recorded by a Japanese speaker) in 13- but not in 7- and 10-month-old Japanese-learning infants (Experiment 1), while revealing the emergence of an LC preference between 7 and 10 months in French-learning infants, using the exact same stimuli. These crosslinguistic behavioral differences, obtained with the same stimuli, thus reflect differences in processing in two populations of infants, which can be linked to differences in the properties of the lexicons of their respective native languages. These findings establish that the emergence of a CL/LC bias is related to exposure to a linguistic input.

Abstract

Humans appear to rely on spatial mappings to represent and describe concepts. The conceptual cuing effect describes the tendency for participants to orient attention to a spatial location following the presentation of an unrelated cue word (e.g., orienting attention upward after reading the word sky). To date, such effects have predominately been explained within the embodied cognition framework, according to which people’s attention is oriented on the basis of prior experience (e.g., sky → up via perceptual simulation). However, this does not provide a compelling explanation for how abstract words have the same ability to orient attention. Why, for example, does dream also orient attention upward? We report on an experiment that investigated the role of language use (specifically, collocation between concept words and spatial words for up and down dimensions) and found that it predicted the cuing effect. The results suggest that language usage patterns may be instrumental in explaining conceptual cuing.

Abstract

Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gon etal., 2014). To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds before and after training, either with tactile feedback, verbal feedback, or no feedback. Audio thresholds were first measured with a spatial bisection task: subjects judged whether the second sound of a three sound sequence was spatially closer to the first or the third sound. The tactile feedback group underwent two audio-tactile feedback sessions of 100 trials, where each auditory trial was followed by the same spatial sequence played on the subject's forearm; auditory spatial bisection thresholds were evaluated after each session. In the verbal feedback condition, the positions of the sounds were verbally reported to the subject after each feedback trial.The no feedback group did the same sequence of trials, with no feedback. Performance improved significantly only after audio-tactile feedback. The results suggest that direct tactile feedback interacts with the auditory spatial localization system, possibly by a process of cross-sensory recalibration. Control tests with the subject rotated suggested that this effect occurs only when the tactile and acoustic sequences are spatially congruent. Our results suggest that the tactile system can be used to recalibrate the auditory sense of space. These results encourage the possibility of designing rehabilitation programs to help blind persons establish a robust auditory sense of space, through training with the tactile modality.

Abstract

This study investigated whether relative lexical proficiency in Dutch and English in child second language (L2) learners is related to executive functioning. Participants were Dutch primary school pupils of three different age groups (4–5, 8–9, and 11–12 years) who either were enrolled in an early-English schooling program or were age-matched controls not on that early-English program. Participants performed tasks that measured switching, inhibition, and working memory. Early-English program pupils had greater knowledge of English vocabulary and more balanced Dutch–English lexicons. In both groups, lexical balance, a ratio measure obtained by dividing vocabulary scores in English by those in Dutch, was related to switching but not to inhibition or working memory performance. These results show that for children who are learning an L2 in an instructional setting, and for whom managing two languages is not yet an automatized process, language balance may be more important than L2 proficiency in influencing the relation between childhood bilingualism and switching abilities.

Abstract

The human capacity to acquire sophisticated language is unmatched in the animal kingdom. Despite the discontinuity in communicative abilities between humans and other primates, language is built on ancient genetic foundations, which are being illuminated by comparative genomics. The genetic architecture of the language faculty is also being uncovered by research into neurodevelopmental disorders that disrupt the normally effortless process of language acquisition. In this article, we discuss the strategies that researchers are using to reveal genetic factors contributing to communicative abilities, and review progress in identifying the relevant genes and genetic variants. The first gene directly implicated in a speech and language disorder was FOXP2. Using this gene as a case study, we illustrate how evidence from genetics, molecular cell biology, animal models and human neuroimaging has converged to build a picture of the role of FOXP2 in neurodevelopment, providing a framework for future endeavors to bridge the gaps between genes, brains and behavior

Abstract

Language is a defining characteristic of the human species, but its foundations remain mysterious. Heritable disorders offer a gateway into biological underpinnings, as illustrated by the discovery that FOXP2 disruptions cause a rare form of speech and language impairment. The genetic architecture underlying language-related disorders is complex, and although some progress has been made, it has proved challenging to pinpoint additional relevant genes with confidence. Next-generation sequencing and genome-wide association studies are revolutionizing understanding of the genetic bases of other neurodevelopmental disorders, like autism and schizophrenia, and providing fundamental insights into the molecular networks crucial for typical brain development. We discuss how a similar genomic perspective, brought to the investigation of language-related phenotypes, promises to yield equally informative discoveries. Moreover, we outline how follow-up studies of genetic findings using cellular systems and animal models can help to elucidate the biological mechanisms involved in the development of brain circuits supporting language.

Abstract

The involvement of neural motor and sensory systems in the processing of language has so far mainly been studied in native (L1) speakers. In an fMRI experiment, we investigated whether non-native (L2) semantic representations are rich enough to allow for activation in motor and somatosensory brain areas. German learners of Dutch and a control group of Dutch native speakers made lexical decisions about visually presented Dutch motor and non-motor verbs. Region-of-interest (ROI) and whole-brain analyses indicated that L2 speakers, like L1 speakers, showed significantly increased activation for simple motor compared to non-motor verbs in motor and somatosensory regions. This effect was not restricted to Dutch-German cognate verbs, but was also present for non-cognate verbs. These results indicate that L2 semantic representations are rich enough for motor-related activations to develop in motor and somatosensory areas.

Abstract

In this functional magnetic resonance imaging (fMRI) long-lag priming study, we investigated the processing of Dutch semantically transparent, derived prefix verbs. In such words, the meaning of the word as a whole can be deduced from the meanings of its parts, e.g., wegleggen “put aside.” Many behavioral and some fMRI studies suggest that native (L1) speakers decompose transparent derived words. The brain region usually implicated in morphological decomposition is the left inferior frontal gyrus (LIFG). In non-native (L2) speakers, the processing of transparent derived words has hardly been investigated, especially in fMRI studies, and results are contradictory: some studies find more reliance on holistic (i.e., non-decompositional) processing by L2 speakers; some find no difference between L1 and L2 speakers. In this study, we wanted to find out whether Dutch transparent derived prefix verbs are decomposed or processed holistically by German L2 speakers of Dutch. Half of the derived verbs (e.g., omvallen “fall down”) were preceded by their stem (e.g., vallen “fall”) with a lag of 4–6 words (“primed”); the other half (e.g., inslapen “fall asleep”) were not (“unprimed”). L1 and L2 speakers of Dutch made lexical decisions on these visually presented verbs. Both region of interest analyses and whole-brain analyses showed that there was a significant repetition suppression effect for primed compared to unprimed derived verbs in the LIFG. This was true both for the analyses over L2 speakers only and for the analyses over the two language groups together. The latter did not reveal any interaction with language group (L1 vs. L2) in the LIFG. Thus, L2 speakers show a clear priming effect in the LIFG, an area that has been associated with morphological decomposition. Our findings are consistent with the idea that L2 speakers engage in decomposition of transparent derived verbs rather than processing them holistically

Abstract

Selective brain responses to objects arise within a few hundreds of milliseconds of neural processing, suggesting that visual object recognition is mediated by rapid feed-forward activations. Yet disruption of neural responses in early visual cortex beyond feed-forward processing stages affects object recognition performance. Here, we unite these discrepant findings by reporting that object recognition involves enhanced feedback activity (recurrent processing within early visual cortex) when target objects are embedded in natural scenes that are characterized by high complexity. Human participants performed an animal target detection task on natural scenes with low, medium or high complexity as determined by a computational model of low-level contrast statistics. Three converging lines of evidence indicate that feedback was selectively enhanced for high complexity scenes. First, functional magnetic resonance imaging (fMRI) activity in early visual cortex (V1) was enhanced for target objects in scenes with high, but not low or medium complexity. Second, event-related potentials (ERPs) evoked by target objects were selectively enhanced at feedback stages of visual processing (from ~220 ms onwards) for high complexity scenes only. Third, behavioral performance for high complexity scenes deteriorated when participants were pressed for time and thus less able to incorporate the feedback activity. Modeling of the reaction time distributions using drift diffusion revealed that object information accumulated more slowly for high complexity scenes, with evidence accumulation being coupled to trial-to-trial variation in the EEG feedback response. Together, these results suggest that while feed-forward activity may suffice to recognize isolated objects, the brain employs recurrent processing more adaptively in naturalistic settings, using minimal feedback for simple scenes and increasing feedback for complex scenes.

Abstract

The current study investigated whether point-accompanying characteristics, like vocalizations and hand shape, differentiate infants' underlying motives of prelinguistic pointing. We elicited imperative (requestive) and declarative (expressive and informative) pointing acts in experimentally controlled situations, and analyzed accompanying characteristics. Experiment 1 revealed that prosodic characteristics of point-accompanying vocalizations distinguished requestive from both expressive and informative pointing acts, with little differences between the latter two. In addition, requestive points were more often realized with the whole hand than the index finger, while this was the opposite for expressive and informative acts. Experiment 2 replicated Experiment 1, revealing distinct prosodic characteristics for requestive pointing also when the referent was distal and when it had an index-finger shape. Findings reveal that beyond the social context, point-accompanying vocalizations give clues to infants' underlying intentions when pointing.

Abstract

The genetic determinants of cerebral asymmetries are unknown. Sex differences in asymmetry of the planum temporale, that overlaps Wernicke’s classical language area, have been inconsistently reported. Meta-analysis of previous studies has suggested that publication bias established this sex difference in the literature. Using probabilistic definitions of cortical regions we screened over the cerebral cortex for sexual dimorphisms of asymmetry in 2337 healthy subjects, and found the planum temporale to show the strongest sex-linked asymmetry of all regions, which was supported by two further datasets, and also by analysis with the Freesurfer package that performs automated parcellation of cerebral cortical regions. We performed a genome-wide association scan meta-analysis of planum temporale asymmetry in a pooled sample of 3095 subjects, followed by a candidate-driven approach which measured a significant enrichment of association in genes of the ´steroid hormone receptor activity´ and 'steroid metabolic process' pathways. Variants in the genes and pathways identified may affect the role of the planum temporale in language cognition.

Abstract

The left and right sides of the human brain are specialized for different kinds of information processing, and much of our cognition is lateralized to an extent towards one side or the other. Handedness is a reflection of nervous system lateralization. Roughly ten percent of people are mixed- or left-handed, and they show an elevated rate of reductions or reversals of some cerebral functional asymmetries compared to right-handers. Brain anatomical correlates of left-handedness have also been suggested. However, the relationships of left-handedness to brain structure and function remain far from clear. We carried out a comprehensive analysis of cortical surface area differences between 106 left-handed subjects and 1960 right-handed subjects, measured using an automated method of regional parcellation (FreeSurfer, Destrieux atlas). This is the largest study sample that has so far been used in relation to this issue. No individual cortical region showed an association with left-handedness that survived statistical correction for multiple testing, although there was a nominally significant association with the surface area of a previously implicated region: the left precentral sulcus. Identifying brain structural correlates of handedness may prove useful for genetic studies of cerebral asymmetries, as well as providing new avenues for the study of relations between handedness, cerebral lateralization and cognition.

Abstract

Functional and anatomical asymmetries are prevalent features of the human brain, linked to gender, handedness, and cognition. However, little is known about the neurodevelopmental processes involved. In zebrafish, asymmetries arise in the diencephalon before extending within the central nervous system. We aimed to identify genes involved in the development of subtle, left-right volumetric asymmetries of human subcortical structures using large datasets. We first tested the feasibility of measuring left-right volume differences in such large-scale samples, as assessed by two automated methods of subcortical segmentation (FSL|FIRST and FreeSurfer), using data from 235 subjects who had undergone MRI twice. We tested the agreement between the first and second scan, and the agreement between the segmentation methods, for measures of bilateral volumes of six subcortical structures and the hippocampus, and their volumetric asymmetries. We also tested whether there were biases introduced by left-right differences in the regional atlases used by the methods, by analyzing left-right flipped images. While many bilateral volumes were measured well (scan-rescan r = 0.6-0.8), most asymmetries, with the exception of the caudate nucleus, showed lower repeatabilites. We meta-analyzed genome-wide association scan results for caudate nucleus asymmetry in a combined sample of 3,028 adult subjects but did not detect associations at genome-wide significance (P < 5 × 10-8). There was no enrichment of genetic association in genes involved in left-right patterning of the viscera. Our results provide important information for researchers who are currently aiming to carry out large-scale genome-wide studies of subcortical and hippocampal volumes, and their asymmetries

Abstract

The study of phonetic contrasts and related phenomena, e.g. inter- and intra-speaker variability, often requires to analyse data in the form of measured time series, like f0 contours and formant trajectories. As a consequence, the investigator has to find suitable ways to reduce the raw and abundant numerical information contained in a bundle of time series into a small but sufficient set of numerical descriptors of their shape. This approach requires one to decide in advance which dynamic traits to include in the analysis and which not. For example, a rising pitch gesture may be represented by its duration and slope, hence reducing it to a straight segment, or by a richer coding specifying also whether (and how much) the rising contour is concave or convex, the latter being irrelevant in some context but crucial in others. Decisions become even more complex when a phenomenon is described by a multidimensional time series, e.g. by the first two formants. In this paper we introduce a methodology based on Functional Data Analysis (FDA) that allows the investigator to delegate most of the decisions involved in the quantitative description of multidimensional time series to the data themselves. FDA produces a data-driven parametrisation of the main shape traits present in the data that is visually interpretable, in the same way as slopes or peak heights are. These output parameters are numbers that are amenable to ordinary statistical analysis, e.g. linear (mixed effects) models. FDA is also able to capture correlations among different dimensions of a time series, e.g. between formants F1 and F2. We present FDA by means of an extended case study on diphthong – hiatus distinction in Spanish, a contrast that involves duration, formant trajectories and pitch contours.

Abstract

In order to make sense of the world, humans tend to see causation almost everywhere. Although most causal relations may seem straightforward, they are not always construed in the same way cross-culturally. In this study, we investigate concepts of ‘chance’, ‘coincidence’ or ‘randomness’ that refer to assumed relations between intention, action, and outcome in situations, and we ask how people from different cultures make sense of such non-law-like connections. Based on a framework proposed by Alicke (2000), we administered a task that aims to be a neutral tool for investigating causal construals cross-culturally and cross-linguistically. Members of four different cultural groups, rural Mayan Yucatec and Tseltal speakers from Mexico and urban students from Mexico and Germany, were presented with a set of scenarios involving various types of causal and non-causal relations and were asked to explain the described events. Three links varied as to whether they were present or not in the scenarios: Intention to Action, Action to Outcome, and Intention to Outcome. Our results show that causality is recognized in all four cultural groups. However, how causality and especially non-law-like causality are interpreted depends on the type of links, the cultural background and the language used. In all three groups, Action to Outcome is the decisive link for recognizing causality. Despite the fact that the two Mayan groups share similar cultural backgrounds, they display different ideologies regarding concepts of non-law causality. The data suggests that the concept of ‘chance’ is not universal, but seems to be an explanation that only some cultural groups draw on to make sense of specific situations. Of particular importance is the existence of linguistic concepts in each language that trigger ideas of causality in the responses from each cultural group

Abstract

A large body of evidence has shown that visual context information can rapidly modulate language comprehension for concrete sentences and when it is mediated by a referential or a lexical-semantic link. What has not yet been examined is whether visual context can also modulate comprehension of abstract sentences incrementally when it is neither referenced by, nor lexically associated with, the sentence. Three eye-tracking reading experiments examined the effects of spatial distance between words (Experiment 1) and objects (Experiment 2 and 3) on participants’ reading times for sentences that convey similarity or difference between two abstract nouns (e.g., ‘Peace and war are certainly different...’). Before reading the sentence, participants inspected a visual context with two playing cards that moved either far apart or close together. In Experiment 1, the cards turned and showed the first two nouns of the sentence (e.g., ‘peace’, ‘war’). In Experiments 2 and 3, they turned but remained blank. Participants’ reading times at the adjective (Experiment 1: first-pass reading time; Experiment 2: total times) and at the second noun phrase (Experiment 3: first-pass times) were faster for sentences that expressed similarity when the preceding words/objects were close together (vs. far apart) and for sentences that expressed dissimilarity when the preceding words/objects were far apart (vs. close together). Thus, spatial distance between words or entirely unrelated objects can rapidly and incrementally modulate the semantic interpretation of abstract sentences.

Abstract

Studies in relatives have generally yielded high heritability estimates for refractive error: twins 75–90%, families 15–70%. However, because related individuals often share a common environment, these estimates are inflated (via misallocation of unique/common environment variance). We calculated a lower-bound heritability estimate for refractive error free from such bias.
Between the ages 7 and 15 years, participants in the Avon Longitudinal Study of Parents and Children (ALSPAC) underwent non-cycloplegic autorefraction at regular research clinics. At each age, an estimate of the variance in refractive error explained by single nucleotide polymorphism (SNP) genetic variants was calculated using genome-wide complex trait analysis (GCTA) using high-density genome-wide SNP genotype information (minimum N at each age=3,404).
The variance in refractive error explained by the SNPs (“SNP heritability”) was stable over childhood: Across age 7–15 years, SNP heritability averaged 0.28 (SE=0.08, p<0.001). The genetic correlation for refractive error between visits varied from 0.77 to 1.00 (all p<0.001) demonstrating that a common set of SNPs was responsible for the genetic contribution to refractive error across this period of childhood. Simulations suggested lack of cycloplegia during autorefraction led to a small underestimation of SNP heritability (adjusted SNP heritability=0.35; SE=0.09). To put these results in context, the variance in refractive error explained (or predicted) by the time participants spent outdoors was <0.005 and by the time spent reading was <0.01, based on a parental questionnaire completed when the child was aged 8–9 years old.
Genetic variation captured by common SNPs explained approximately 35% of the variation in refractive error between unrelated subjects. This value sets an upper limit for predicting refractive error using existing SNP genotyping arrays, although higher-density genotyping in larger samples and inclusion of interaction effects is expected to raise this figure toward twin- and family-based heritability estimates. The same SNPs influenced refractive error across much of childhood. Notwithstanding the strong evidence of association between time outdoors and myopia, and time reading and myopia, less than 1% of the variance in myopia at age 15 was explained by crude measures of these two risk factors, indicating that their effects may be limited, at least when averaged over the whole population.

Abstract

Analyses of gray matter concentration (GMC) deficits in patients with schizophrenia (Sz) have identified robust changes throughout the cortex. We assessed the relationships between diagnosis, overall symptom severity, and patterns of gray matter in the largest aggregated structural imaging dataset to date. We performed both source-based morphometry (SBM) and voxel-based morphometry (VBM) analyses on GMC images from 784 Sz and 936 controls (Ct) across 23 scanning sites in Europe and the United States. After correcting for age, gender, site, and diagnosis by site interactions, SBM analyses showed 9 patterns of diagnostic differences. They comprised separate cortical, subcortical, and cerebellar regions. Seven patterns showed greater GMC in Ct than Sz, while 2 (brainstem and cerebellum) showed greater GMC for Sz. The greatest GMC deficit was in a single pattern comprising regions in the superior temporal gyrus, inferior frontal gyrus, and medial frontal cortex, which replicated over analyses of data subsets. VBM analyses identified overall cortical GMC loss and one small cluster of increased GMC in Sz, which overlapped with the SBM brainstem component. We found no significant association between the component loadings and symptom severity in either analysis. This mega-analysis confirms that the commonly found GMC loss in Sz in the anterior temporal lobe, insula, and medial frontal lobe form a single, consistent spatial pattern even in such a diverse dataset. The separation of GMC loss into robust, repeatable spatial patterns across multiple datasets paves the way for the application of these methods to identify subtle genetic and clinical cohort effects.

Abstract

Current views on the neurobiological underpinnings of language are discussed that deviate in a number of ways from the classical Wernicke–Lichtheim–Geschwind model. More areas than Broca's and Wernicke's region are involved in language. Moreover, a division along the axis of language production and language comprehension does not seem to be warranted. Instead, for central aspects of language processing neural infrastructure is shared between production and comprehension. Three different accounts of the role of Broca's area in language are discussed. Arguments are presented in favor of a dynamic network view, in which the functionality of a region is co-determined by the network of regions in which it is embedded at particular moments in time. Finally, core regions of language processing need to interact with other networks (e.g. the attentional networks and the ToM network) to establish full functionality of language and communication.

Abstract

A hallmark of human language is that we combine lexical building blocks retrieved from memory in endless new ways. This combinatorial aspect of language is referred to as unification. Here we focus on the neurobiological infrastructure for syntactic and semantic unification. Unification is characterized by a high-speed temporal profile including both prediction and integration of retrieved lexical elements. A meta-analysis of numerous neuroimaging studies reveals a clear dorsal/ventral gradient in both left inferior frontal cortex and left posterior temporal cortex, with dorsal foci for syntactic processing and ventral foci for semantic processing. In addition to core areas for unification, further networks need to be recruited to realize language-driven communication to its full extent. One example is the theory of mind network, which allows listeners and readers to infer the intended message (speaker meaning) from the coded meaning of the linguistic utterance. This indicates that sensorimotor simulation cannot handle all of language processing.

Abstract

Children’s songs often contain rhyming words at phrase endings. In this study, we investigated whether infants can already recognize this phonological pattern in songs. Earlier studies using lists of spoken words were equivocal on infants’ spontaneous processing of rhymes (Hayes, Slater, & Brown, 2000; Jusczyk, Goodman, & Baumann, 1999). Songs, however, constitute an ecologically valid rhyming stimulus, which could allow for spontaneous processing of this phonological pattern in infants. Novel children’s songs with rhyming and non-rhyming lyrics using pseudo-words were presented to 35 9-month-old Dutch infants using the Headturn Preference Procedure. Infants on average listened longer to the non-rhyming songs, with around half of the infants however exhibiting a preference for the rhyming songs. These results highlight that infants have the processing abilities to benefit from their natural rhyming input for the development of their phonological abilities.

Abstract

All natural languages develop devices to communicate who did what to whom. Elicited pantomime provides one model for studying this process, by providing a window into how humans (hearing non-signers) behave in a natural communicative modality (silent gesture) without established conventions from a grammar. Most studies in this paradigm focus on production, although they sometimes make assumptions about how comprehenders would likely behave. Here, we directly assess how naïve speakers of English (Experiments 1 & 2), Korean (Experiment 1), and Turkish (Experiment 2) comprehend pantomimed descriptions of transitive events, which are either semantically reversible (Experiments 1 & 2) or not (Experiment 2). Contrary to previous assumptions, we find no evidence that Person-Person-Action sequences are ambiguous to comprehenders, who simply adopt an agent-first parsing heuristic for all constituent orders. We do find that Person-Action-Person sequences yield the most consistent interpretations, even in native speakers of SOV languages. The full range of behavior in both production and comprehension provides counter-evidence to the notion that producers’ utterances are motivated by the needs of comprehenders. Instead, we argue that production and comprehension are subject to different sets of cognitive pressures, and that the dynamic interaction between these competing pressures can help explain synchronic and diachronic constituent order phenomena in natural human languages, both signed and spoken.

Abstract

This paper joins studies of linguistic variation (e.g. Labov 1972; Dubois & Horvath 2000) and discourse (e.g. Jaworski & Lawson 2005; Jaworski & Pritchard 2005; Thurlow & Jaworski 2010) that consider the intersection between language and tourism. By examining the language attitudes that tourists hold toward linguistic variability in their host community, we find that attitudes differ by context and with respect to tourists’ travel motivations. We suggest that these results are particularly likely in a context like Edinburgh, Scotland, where linguistic variation has an iconic link to place authenticity. We propose that the joint commodification of ‘intelligibility’ and ‘authenticity’ explains this variability. The results raise questions about how the commodity value of travel motivation and the associated context of language use influence language attitudes.

Abstract

In the recent past the work on large-scale linguistic distributions across the globe has intensified considerably. Work on macro-areal relationships in Africa (Güldemann, 2010) suggests that the shape of convergence areas may be determined by climatic factors and geophysical features such as mountains, water bodies, coastlines, etc. Worldwide data is now available for geophysical features as well as linguistic features, including numeral systems and basic constituent order. We explore the possibility that the shape of areal aggregations of individual features in these two linguistic domains correlates with Köppen-Geiger climate zones. Furthermore, we test the hypothesis that the shape of such areal feature aggregations is determined by the contour of adjacent geophysical features like mountain ranges or coastlines. In these first basic tests, we do not find clear evidence that either Köppen-Geiger climate zones or the contours of geophysical features are major predictors for the linguistic data at hand

Abstract

While the notion of the ‘area’ or ‘Sprachbund’ has a long history in linguistics, with geographically-defined regions frequently cited as a useful means to explain typological distributions, the problem of delimiting areas has not been well addressed. Lists of general-purpose, largely independent ‘macro-areas’ (typically continent size) have been proposed as a step to rule out contact as an explanation for various large-scale linguistic phenomena. This squib points out some problems in some of the currently widely-used predetermined areas, those found in the World Atlas of Language Structures (Haspelmath et al., 2005). Instead, we propose a principled division of the world’s landmasses into six macro-areas that arguably have better geographical independence properties

Abstract

Ethnologue (http://www.ethnologue.com) is the most widely consulted inventory of the world’slanguages used today. The present review article looks carefully at the goals and description of the content of the Ethnologue’s 16th, 17th, and 18th editions, and reports on a comprehensive survey of the accuracy of the inventory itself. While hundreds of spurious and missing languages can be documented for Ethnologue, it is at present still better than any other nonderivative work of the same scope, in all aspects but one. Ethnologue fails to disclose the sources for the information presented, at odds with well-established scientific principles. The classification of languages into families in Ethnologue is also evaluated, and found to be far off from that argued in the specialist literature on the classification of individual languages. Ethnologue is frequently held to be splitting: that is, it tends to recognize more languages than an application of the criterion of mutual intelligibility would yield. By means of a random sample, we find that, indeed, with confidence intervals, the number of mutually unintelligible languages is on average 85% of the number found in Ethnologue. © 2015, Linguistic Society of America. All rights reserved.

Abstract

Whitesands is an Oceanic language of the southern Vanuatu subgroup. Like the related languages of southern Vanuatu, Whitesands has developed a clause-linkage system which monitors referent continuity on new clauses – typically contrasting with the previous clause. In this chapter I address how the construction interacts with topic continuity in discourse. I outline the morphosyntactic form of this anaphoric co-reference device. From a functionalist perspective, I show how the system is used in natural discourse and discuss its restrictions with respect to relative and complement clauses. I conclude with a discussion on its interactions with theoretical notions of information structure – in particular the nature of presupposed versus asserted clauses, information back- and foregrounding and how these affect the use of the switch-reference system

Abstract

This paper investigates whether individual speakers forming a homogeneous group differ in their choice and pronunciation of words when engaged in casual conversation, and if so, how they differ. More specifically, it examines whether the Balanced Winnow classifier is able to distinguish between the twenty speakers of the Ernestus Corpus of Spontaneous Dutch, who all have the same social background. To examine differences in choice and pronunciation of words, instead of characteristics of the speech signal itself, classification was based on lexical and pronunciation features extracted from hand-made orthographic and automatically generated broad phonetic transcriptions. The lexical features consisted of words and two-word combinations. The pronunciation features represented pronunciation variations at the word and phone level that are typical for casual speech. The best classifier achieved a performance of 79.9% and was based on the lexical features and on the pronunciation features representing single phones and triphones. The speakers must thus differ from each other in these features. Inspection of the relevant features indicated that, among other things, the words relevant for classification generally do not contain much semantic content, and that speakers differ not only from each other in the use of these words but also in their pronunciation.

Abstract

This paper studies the robustness of exemplar effects in word comprehension by means of four long-term priming experiments with lexical decision tasks in Dutch. A prime and target represented the same word type and were presented with the same or different degree of reduction. In Experiment 1, participants heard only a small number of trials, a large proportion of repeated words, and stimuli produced by only one speaker. They recognized targets more quickly if these represented the same degree of reduction as their primes, which forms additional evidence for the exemplar effects reported in the literature. Similar effects were found for two speakers who differ in their pronunciations. In Experiment 2, with a smaller proportion of repeated words and more trials between prime and target, participants recognized targets preceded by primes with the same or a different degree of reduction equally quickly. Also, in Experiments 3 and 4, in which listeners were not exposed to one but two types of pronunciation variation (reduction degree and speaker voice), no exemplar effects arose. We conclude that the role of exemplars in speech comprehension during natural conversations, which typically involve several speakers and few repeated content words, may be smaller than previously assumed.

Abstract

Treatment with serotonin reuptake inhibitors (SSRI) has been associated with an increased risk of preterm birth, but causality remains unclear. While placental CRH production is correlated with gestational length and preterm birth, it has been difficult to establish if psychological stress or mental health problems are associated with increased CRH levels. This study compared second trimester CRH serum concentrations in pregnant women on SSRI treatment (n=207) with untreated depressed women (n=56) and controls (n=609). A secondary aim was to investigate the combined effect of SSRI treatment and CRH levels on gestational length and risk for preterm birth. Women on SSRI treatment had significantly higher second trimester CRH levels than controls, and untreated depressed women. CRH levels and SSRI treatment were independently associated with shorter gestational length. The combined effect of SSRI treatment and high CRH levels yielded the highest risk estimate for preterm birth. SSRI treatment during pregnancy is associated with increased CRH levels. However, the elevated risk for preterm birth in SSRI users appear not to be mediated by increased placental CRH production, instead CRH appear as an independent risk factor for shorter gestational length and preterm birth.

Abstract

The epileptic encephalopathies are a clinically and aetiologically heterogeneous subgroup of epilepsy syndromes. Most epileptic encephalopathies have a genetic cause and patients are often found to carry a heterozygous de novo mutation in one of the genes associated with the disease entity. Occasionally recessive mutations are identified: a recent publication described a distinct neonatal epileptic encephalopathy (MIM 615905) caused by autosomal recessive mutations in the SLC13A5 gene. Here, we report eight additional patients belonging to four different families with autosomal recessive mutations in SLC13A5. SLC13A5 encodes a high affinity sodium-dependent citrate transporter, which is expressed in the brain. Neurons are considered incapable of de novo synthesis of tricarboxylic acid cycle intermediates; therefore they rely on the uptake of intermediates, such as citrate, to maintain their energy status and neurotransmitter production. The effect of all seven identified mutations (two premature stops and five amino acid substitutions) was studied in vitro, using immunocytochemistry, selective western blot and mass spectrometry. We hereby demonstrate that cells expressing mutant sodium-dependent citrate transporter have a complete loss of citrate uptake due to various cellular loss-of-function mechanisms. In addition, we provide independent proof of the involvement of autosomal recessive SLC13A5 mutations in the development of neonatal epileptic encephalopathies, and highlight teeth hypoplasia as a possible indicator for SLC13A5 screening. All three patients who tried the ketogenic diet responded well to this treatment, and future studies will allow us to ascertain whether this is a recurrent feature in this severe disorder.

Abstract

Recent decades have ushered in tremendous progress in understanding the neural basis of language. Most of our current knowledge on language and the brain, however, is derived from lab-based experiments that are far removed from everyday language use, and that are inspired by questions originating in linguistic and psycholinguistic contexts. In this paper we argue that in order to make progress, the field needs to shift its focus to understanding the neurobiology of naturalistic language comprehension. We present here a new conceptual framework for understanding the neurobiological organization of language comprehension. This framework is non-language-centered in the computational/neurobiological constructs it identifies, and focuses strongly on context. Our core arguments address three general issues: (i) the difficulty in extending language-centric explanations to discourse; (ii) the necessity of taking context as a serious topic of study, modeling it formally and acknowledging the limitations on external validity when studying language comprehension outside context; and (iii) the tenuous status of the language network as an explanatory construct. We argue that adopting this framework means that neurobiological studies of language will be less focused on identifying correlations between brain activity patterns and mechanisms postulated by psycholinguistic theories. Instead, they will be less self-referential and increasingly more inclined towards integration of language with other cognitive systems, ultimately doing more justice to the neurobiological organization of language and how it supports language as it is used in everyday life.

Abstract

All primates learn things from conspecifics socially, but it is not clear whether they conform to the behavior of these conspecifics—if conformity is defined as overriding individually acquired behavioral tendencies in order to copy peers’ behavior. In the current study, chimpanzees, orangutans, and 2-year-old human children individually acquired a problem-solving strategy. They then watched several conspecific peers demonstrate an alternative strategy. The children switched to this new, socially demonstrated strategy in roughly half of all instances, whereas the other two great-ape species almost never adjusted their behavior to the majority’s. In a follow-up study, children switched much more when the peer demonstrators were still present than when they were absent, which suggests that their conformity arose at least in part from social motivations. These results demonstrate an important difference between the social learning of humans and great apes, a difference that might help to account for differences in human and nonhuman cultures

Abstract

Literacy affects many aspects of cognitive and linguistic processing. Among them, it increases the salience of words as units of linguistic processing. Here, we explored the impact of literacy acquisition on children’s learning of an artifical language. Recent accounts of L1–L2 differences relate adults’ greater difficulty with language learning to their smaller reliance on multiword units. In particular, multiword units are claimed to be beneficial for learning opaque grammatical relations like grammatical gender. Since literacy impacts the reliance on words as units of processing, we ask if and how acquiring literacy may change children’s language-learning results. We looked at children’s success in learning novel noun labels relative to their success in learning article-noun gender agreement, before and after learning to read. We found that preliterate first graders were better at learning agreement (larger units) than at learning nouns (smaller units), and that the difference between the two trial types significantly decreased after these children acquired literacy. In contrast, literate third graders were as good in both trial types. These findings suggest that literacy affects not only language processing, but also leads to important differences in language learning. They support the idea that some of children’s advantage in language learning comes from their previous knowledge and experience with language—and specifically, their lack of experience with written texts.

Abstract

Objective
The aim was to assess whether loci associated with metabolic traits also have a significant role in BMI and mental traits/disorders
Methods
We first assessed the number of single nucleotide polymorphisms (SNPs) with genome-wide significance for human metabolism (NHGRI-EBI Catalog). These 516 SNPs (216 independent loci) were looked-up in genome-wide association studies for association with body mass index (BMI) and the mental traits/disorders educational attainment, neuroticism, schizophrenia, well-being, anxiety, depressive symptoms, major depressive disorder, autism-spectrum disorder, attention-deficit/hyperactivity disorder, Alzheimer's disease, bipolar disorder, aggressive behavior, and internalizing problems. A strict significance threshold of p < 6.92 × 10−6 was based on the correction for 516 SNPs and all 14 phenotypes, a second less conservative threshold (p < 9.69 × 10−5) on the correction for the 516 SNPs only.
Results
19 SNPs located in nine independent loci revealed p-values < 6.92 × 10−6; the less strict criterion was met by 41 SNPs in 24 independent loci. BMI and schizophrenia showed the most pronounced genetic overlap with human metabolism with three loci each meeting the strict significance threshold. Overall, genetic variation associated with estimated glomerular filtration rate showed up frequently; single metabolite SNPs were associated with more than one phenotype. Replications in independent samples were obtained for BMI and educational attainment.
Conclusions
Approximately 5–10% of the regions involved in the regulation of blood/urine metabolite levels seem to also play a role in BMI and mental traits/disorders and related phenotypes. If validated in metabolomic studies of the respective phenotypes, the associated blood/urine metabolites may enable novel preventive and therapeutic strategies.

Abstract

The present study was designed to examine the impact of bilingualism on the neuronal activity in different executive control processes namely conflict monitoring, control implementation (i.e., interference suppression and conflict resolution) and overcoming of inhibition. Twenty-two highly proficient but non-balanced successive French–German bilingual adults and 22 monolingual adults performed a combined Stroop/Negative priming task while event-related potential (ERP) were recorded online. The data revealed that the ERP effects were reduced in bilinguals in comparison to monolinguals but only in the Stroop task and limited to the N400 and the sustained fronto-central negative-going potential time windows. This result suggests that bilingualism may impact the process of control implementation rather than the process of conflict monitoring (N200). Critically, our study revealed a differential time course of the involvement of the anterior cingulate cortex (ACC) and the prefrontal cortex (PFC) in conflict processing. While the ACC showed major activation in the early time windows (N200 and N400) but not in the latest time window (late sustained negative-going potential), the PFC became unilaterally active in the left hemisphere in the N400 and the late sustained negative-going potential time windows. Taken together, the present electroencephalography data lend support to a cascading neurophysiological model of executive control processes, in which ACC and PFC may play a determining role.

Abstract

The interaction between C-X-C chemokine receptor type 4 (CXCR4) and its cognate ligand C-X-C motif chemokine ligand 12 (CXCL12) plays a critical role in regulating hematopoietic stem cell activation and subsequent cellular mobilization. Extensive studies of these genes have been conducted in mammals, but much less is known about the expression and function of CXCR4 and CXCL12 in non-mammalian vertebrates. In the present study, we identify simultaneous expression of CXCR4 and CXCL12 orthologs in the epigonal organ (the primary hematopoietic tissue) of the little skate, Leucoraja erinacea. Genetic and phylogenetic analyses were functionally supported by significant mobilization of leukocytes following administration of Plerixafor, a CXCR4 antagonist and clinically important drug. Our results provide evidence that, as in humans, Plerixafor disrupts CXCR4/CXCL12 binding in the little skate, facilitating release of leukocytes into the bloodstream. Our study illustrates the value of the little skate as a model organism, particularly in studies of hematopoiesis and potentially for preclinical research on hematological and vascular disorders.

Abstract

The multilingual brain implements mechanisms that serve to select the appropriate language as a function of the communicative environment. Engaging these mechanisms on a regular basis appears to have consequences for brain structure and function. Studies have implicated the caudate nuclei as important nodes in polyglot language control processes, and have also shown structural differences in the caudate nuclei in bilingual compared to monolingual populations. However, the majority of published work has focused on the categorical differences between monolingual and bilingual individuals, and little is known about whether these findings extend to multilingual individuals, who have even greater language control demands. In the present paper, we present an analysis of the volume and morphology of the caudate nuclei, putamen, pallidum and thalami in 75 multilingual individuals who speak three or more languages. Volumetric analyses revealed a significant relationship between multilingual experience and right caudate volume, as well as a marginally significant relationship with left caudate volume. Vertex-wise analyses revealed a significant enlargement of dorsal and anterior portions of the left caudate nucleus, known to have connectivity with executive brain regions, as a function of multilingual expertise. These results suggest that multilingual expertise might exercise a continuous impact on brain structure, and that as additional languages beyond a second are acquired, the additional demands for linguistic and cognitive control result in modifications to brain structures associated with language management processes.

Abstract

Bilingual listeners comprehend speech-in-noise better in their native than non-native language. This native-language benefit is thought to arise from greater use of top-down linguistic information to assist degraded speech comprehension. Using functional magnetic resonance imaging, we recently showed that left angular gyrus activation is modulated when semantic context is used to assist native language speech-in-noise comprehension (Golestani, Hervais-Adelman, Obleser, & Scott, 2013). Here, we extend the previous work, by reanalyzing the previous data alongside the results obtained in the non-native language of the same late bilingual participants. We found a behavioral benefit of semantic context in processing speech-in-noise in the native language only, and the imaging results also revealed a native language context effect in the left angular gyrus. We also find a complementary role of lower-level auditory regions during stimulus-driven processing. Our findings help to elucidate the neural basis of the established native language behavioral benefit of speech-in-noise processing. (C) 2014 Elsevier Inc. All rights reserved.

Abstract

We used functional magnetic resonance imaging (fMRI) to longitudinally examine brain plasticity arising from long-term, intensive simultaneous interpretation training. Simultaneous interpretation is a bilingual task with heavy executive control demands. We compared brain responses observed during simultaneous interpretation with those observed during simultaneous speech repetition (shadowing) in a group of trainee simultaneous interpreters, at the beginning and at the end of their professional training program. Age, sex and language-proficiency matched controls were scanned at similar intervals. Using multivariate pattern classification, we found distributed patterns of changes in functional responses from the first to second scan that distinguished the interpreters from the controls. We also found reduced recruitment of the right caudate nucleus during simultaneous interpretation as a result of training. Such practice-related change is consistent with decreased demands on multilingual language control as the task becomes more automatized with practice. These results demonstrate the impact of simultaneous interpretation training on the brain functional response in a cerebral structure that is not specifically linguistic, but that is known to be involved in learning, in motor control, and in a variety of domain-general executive functions. Along with results of recent studies showing functional and structural adaptations in the caudate nuclei of experts in a broad range of domains, our results underline the importance of this structure as a central node in expertise-related networks. (C) 2015 Elsevier Inc. All rights reserved.

Abstract

A commentary on
Broca Pars Triangularis Constitutes a “Hub” of the Language-Control Network during Simultaneous Language Translation

by Elmer, S. (2016). Front. Hum. Neurosci. 10:491. doi: 10.3389/fnhum.2016.00491

Elmer (2016) conducted an fMRI investigation of “simultaneous language translation” in five participants. The article presents group and individual analyses of German-to-Italian and Italian-to-German translation, confined to a small set of anatomical regions previously reported to be involved in multilingual control. Here we take the opportunity to discuss concerns regarding certain aspects of the study.

Abstract

We used functional magnetic resonance imaging (fMRI) to examine the neural basis of extreme multilingual language control in a group of 50 multilingual participants. Comparing brain responses arising during simultaneous interpretation (SI) with those arising during simultaneous repetition revealed activation of regions known to be involved in speech perception and production, alongside a network incorporating the caudate nucleus that is known to be implicated in domain-general cognitive control. The similarity between the networks underlying bilingual language control and general executive control supports the notion that the frequently reported bilingual advantage on executive tasks stems from the day-to-day demands of language control in the multilingual brain. We examined neural correlates of the management of simultaneity by correlating brain activity during interpretation with the duration of simultaneous speaking and hearing. This analysis showed significant modulation of the putamen by the duration of simultaneity. Our findings suggest that, during SI, the caudate nucleus is implicated in the overarching selection and control of the lexico-semantic system, while the putamen is implicated in ongoing control of language output. These findings provide the first clear dissociation of specific dorsal striatum structures in polyglot language control, roles that are consistent with previously described involvement of these regions in nonlinguistic executive control.

Abstract

Fast and automatic behavioral responses are required to avoid collision with an approaching stimulus. Accordingly, looming stimuli have been found to be highly salient and efficient attractors of attention due to the implication of potential collision and potential threat. Here, we address the question of whether looming motion is processed in the absence of any functional primary visual cortex and consequently without awareness. For this, we investigated a patient (TN) suffering from complete, bilateral damage to his primary visual cortex. Using an fMRI paradigm, we measured TN's brain activation during the presentation of looming, receding, rotating, and static point lights, of which he was unaware. When contrasted with other conditions, looming was found to produce bilateral activation of the middle temporal areas, as well as the superior temporal sulcus and inferior parietal lobe (IPL). The latter are generally thought to be involved in multisensory processing of motion in extrapersonal space, as well as attentional capture and saliency. No activity was found close to the lesioned V1 area. This demonstrates that looming motion is processed in the absence of awareness through direct subcortical projections to areas involved in multisensory processing of motion and saliency that bypass V-1.

Abstract

Superiority in visual search for individuals diagnosed with autism spectrum disorder (ASD) is a well-reported finding. We administered two visual search tasks to individuals with ASD and matched controls. One showed no difference between the groups, and one did show the expected superior performance for individuals with ASD. These results offer an explanation, formulated in terms of load theory. We suggest that there is a limit to the superiority in visual search for individuals with ASD, related to the perceptual load of the stimuli. When perceptual load becomes so high that no additional task-(ir)relevant information can be processed, performance will be based on single stimulus identification, in which no differences between individuals with ASD and controls have been demonstrated

Abstract

Epilepsy is a frequent feature of neurodevelopmental disorders (NDDs), but little is known about genetic differences between NDDs with and without epilepsy. We analyzed de novo variants (DNVs) in 6,753 parent–offspring trios ascertained to have different NDDs. In the subset of 1,942 individuals with NDDs with epilepsy, we identified 33 genes with a significant excess of DNVs, of which SNAP25 and GABRB2 had previously only limited evidence of disease association. Joint analysis of all individuals with NDDs also implicated CACNA1E as a novel disease-associated gene. Comparing NDDs with and without epilepsy, we found missense DNVs, DNVs in specific genes, age of recruitment, and severity of intellectual disability to be associated with epilepsy. We further demonstrate the extent to which our results affect current genetic testing as well as treatment, emphasizing the benefit of accurate genetic diagnosis in NDDs with epilepsy.

Abstract

Participants’ performance differs when conducting a task in the presence of a secondary individual, moreover the opinion the participant has of this individual also plays a role. Using EEG, we investigated how previous interactions with, and evaluations of, an avatar in virtual reality subsequently influenced attentional allocation to the face of that avatar. We focused on changes in the alpha activity as an index of attentional allocation. We found that the onset of an avatar’s face whom the participant had developed a rapport with induced greater alpha suppression. This suggests greater attentional resources are allocated to the interacted-with avatars. The evaluative ratings of the avatar induced a U-shaped change in alpha suppression, such that participants paid most attention when the avatar was rated as average. These results suggest that attentional allocation is an important element of how behaviour is altered in the presence of a secondary individual and is modulated by our opinion of that individual.

Abstract

The highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate how common genetic variants affect the structure of these brain regions, here we conduct genome-wide association studies of the volumes of seven subcortical regions and the intracranial volume derived from magnetic resonance images of 30,717 individuals from 50 cohorts. We identify five novel genetic variants influencing the volumes of the putamen and caudate nucleus. We also find stronger evidence for three loci with previously established influences on hippocampal volume and intracranial volume. These variants show specific volumetric effects on brain structures rather than global effects across structures. The strongest effects were found for the putamen, where a novel intergenic locus with replicable influence on volume (rs945270; P = 1.08 × 10-33; 0.52% variance explained) showed evidence of altering the expression of the KTN1 gene in both brain and blood tissue. Variants influencing putamen volume clustered near developmental genes that regulate apoptosis, axon guidance and vesicle transport. Identification of these genetic variants provides insight into the causes of variability in human brain development, and may help to determine mechanisms of neuropsychiatric dysfunction

Abstract

To accomplish a smooth transition in conversation from one speaker to the next, a tight coordination of interaction between speakers is required. Recent studies of adult conversation suggest that this close timing of interaction may well be a universal feature of conversation. In the present paper, we set out to assess the development of this close timing of turns in infancy in vocal exchanges between mothers and infants. Previous research has demonstrated an early sensitivity to timing in interactions (e.g. Murray & Trevarthen, 1985). In contrast, less is known about infants’ abilities to produce turns in a timely manner and existing findings are rather patchy. We conducted a longitudinal study of twelve mother-infant dyads in free-play interactions at the ages of 3, 4, 5, 9, 12 and 18 months. Based on existing work and the predictions made by the Interaction Engine Hypothesis (Levinson, 2006), we expected that infants would begin to develop the temporal properties of turn-taking early in infancy but that their timing of turns would slow down at 12 months, which is around the time when infants start to produce their first words. Findings were consistent with our predictions: Infants were relatively fast at timing their turn early in infancy but slowed down towards the end of the first year. Furthermore, the changes observed in infants’ turn-timing skills were not caused by changes in maternal timing, which remained stable across the 3-18 month period. However, the slowing down of turn-timing started somewhat earlier than predicted: at 9 months.

Abstract

During conversation, people integrate information from co-speech hand gestures with information in spoken language. For example, after hearing the sentence, "A piece of the log flew up and hit Carl in the face" while viewing a gesture directed at the nose, people tend to later report that the log hit Carl in the nose (information only in gesture) rather than in the face (information in speech). The cognitive and neural mechanisms that support the integration of gesture with speech are unclear. One possibility is that the hippocampus known for its role in relational memory and information integration is necessary for integrating gesture and speech. To test this possibility, we examined how patients with hippocampal amnesia and healthy and brain-damaged comparison participants express information from gesture in a narrative retelling task. Participants watched videos of an experimenter telling narratives that included hand gestures that contained supplementary information. Participants were asked to retell the narratives and their spoken retellings were assessed for the presence of information from gesture. For features that had been accompanied by supplementary gesture, patients with amnesia retold fewer of these features overall and fewer retellings that matched the speech from the narrative. Yet their retellings included features that contained information that had been present uniquely in. gesture in amounts that were not reliably different from comparison groups. Thus, a functioning hippocampus is not necessary for gesture-speech integration over short timescales. Providing unique information in gesture may enhance communication for individuals with declarative memory impairment, possibly via non-declarative memory mechanisms.

Abstract

Three eye-tracking experiments investigated the impact of the complexity of the visual environment on the likelihood of word-object mapping taking place at phonological, semantic and visual levels of representation during language-mediated visual search. Dutch participants heard spoken target words while looking at four objects embedded in displays of different complexity and indicated the presence or absence of the target object. During filler trials the target objects were present, but during experimental trials they were absent and the display contained various competitor objects. For example, given the target word “beaker”, the display contained a phonological (a beaver, bever), a shape (a bobbin, klos), a semantic (a fork, vork) competitor, and an unrelated distractor (an umbrella, paraplu). When objects were presented in simple four-object displays (Experiment 2), there were clear attentional biases to all three types of competitors replicating earlier research (Huettig and McQueen, 2007). When the objects were embedded in complex scenes including four human-like characters or four meaningless visual shapes (Experiments 1, 3), there were biases in looks to visual and semantic but not to phonological competitors. In both experiments, however, we observed evidence for inhibition in looks to phonological competitors, which suggests that the phonological forms of the objects nevertheless had been retrieved. These findings suggest that phonological word-object mapping is contingent upon the nature of the visual environment and add to a growing body of evidence that the nature of our visual surroundings induces particular modes of processing during language-mediated visual search.

Abstract

The relationship between the production and the comprehension systems has recently become a topic of interest for many psycholinguists. It has been argued that these systems are tightly linked and in particular that listeners use the production system to predict upcoming content. In this study, we tested how similar production and prediction processes are in a novel version of the visual world paradigm. Dutch speaking participants (native speakers in Experiment 1; German-Dutch bilinguals in Experiment 2) listened to mathematical equations while looking at a clock face featuring the numbers 1 to 12. On alternating trials, they either heard a complete equation ("three plus eight is eleven") or they heard the first part ("three plus eight is") and had to produce the result ("eleven") themselves. Participants were encouraged to look at the relevant numbers throughout the trial. Their eye movements were recorded and analyzed. We found that the participants' eye movements in the two tasks were overall very similar. They fixated the first and second number of the equations shortly after they were mentioned, and fixated the result number well before they named it on production trials and well before the recorded speaker named it on comprehension trials. However, all fixation latencies were shorter on production than on comprehension trials. These findings suggest that the processes involved in planning to say a word and anticipating hearing a word are quite similar, but that people are more aroused or engaged when they intend to respond than when they merely listen to another person.

Abstract

Theories of embodied language comprehension have proposed that language is understood through perceptual simulation of the sensorimotor characteristics of its meaning. Strong support for this claim requires demonstration of encoding-based activation of sensorimotor representations that is distinct from task-related or goal-driven processes. Participants in 3 eye-tracking experiments were presented with triplets of either numbers or object and animal names. In Experiment 1, participants indicated whether the size of the referent of the middle object or animal name was in between the size of the 2 outer items. In Experiment 2, the object and animal names were encoded for an immediate recognition memory task. In Experiment 3, participants completed the same comparison task of Experiment 1 for both words and numbers. During the comparison tasks, word and number decision times showed a symbolic distance effect, such that response time was inversely related to the size difference between the items. A symbolic distance effect was also observed for animal and object encoding times in cases where encoding time likely reflected some goal-driven processes as well. When semantic size was irrelevant to the task (Experiment 2), it had no effect on word encoding times. Number encoding times showed a numerical distance priming effect: Encoding time increased with numerical difference between items. Together these results suggest that while activation of numerical magnitude representations is encoding-based as well as goal-driven, activation of size information associated with words is goal-driven and does not occur automatically during encoding. This conclusion challenges strong theories of embodied cognition which claim that language comprehension consists of activation of analog sensorimotor representations irrespective of higher level processes related to context or task-specific goals

Abstract

Two eye-tracking experiments were conducted in which the manual response mode typically used in lexical decision tasks (LDTs) was replaced with an eye-movement response through a sequence of 3 words. This ocular LDT combines the explicit control of task goals found in LDTs with the highly practiced ocular response used in reading text. In Experiment 1, forward saccades indicated an affirmative lexical decision (LD) on each word in the triplet. In Experiment 2, LD responses were delayed until all 3 letter strings had been read. The goal of the study was to evaluate the contribution of task goals and response mode to semantic priming. Semantic priming is very robust in tasks that involve recognition of words in isolation, such as LDT, but limited during text reading, as measured using eye movements. Gaze durations in both experiments showed robust semantic priming even though ocular response times were much shorter than manual LDs for the same words in the English Lexicon Project. Ex-Gaussian distribution fits revealed that the priming effect was concentrated in estimates of tau (τ), meaning that priming was most pronounced in the slow tail of the distribution. This pattern shows differential use of the prime information, which may be more heavily recruited in cases in which the LD is difficult, as indicated by longer response times. Compared with the manual LD responses, ocular LDs provide a more sensitive measure of this task-related influence on word recognition as measured by the LDT.

Abstract

Conversation Analysis (CA) is an inductive, micro-analytic, and predominantly qualitative
method for studying human social interactions. This chapter describes and illustrates the basic
methods of CA. We first situate the method by describing its sociological foundations, key areas
of analysis, and particular approach in using naturally occurring data. The bulk of the chapter is
devoted to practical explanations of the typical conversation analytic process for collecting data
and producing an analysis. We analyze a candidate interactional practice – the assessmentimplicative
interrogative – using real data extracts as a demonstration of the method, explicitly
laying out the relevant questions and considerations for every stage of an analysis. The chapter
concludes with some discussion of quantitative approaches to conversational interaction, and
links between CA and psycholinguistic concerns

Abstract

How do conversational participants continue with turn-by-turn talk after a momentary lapse? If all participants forgo the option to speak at possible sequence completion, an extended silence may emerge that can indicate a lack of anything to talk about next. For the interaction to proceed recognizably as a conversation, the postlapse turn needs to implicate more talk. Using conversation analysis, I examine three practical alternatives regarding sequentially implicative postlapse turns: Participants may move to end the interaction, continue with some prior matter, or start something new. Participants are shown using resources grounded in the interaction’s overall structural organization, the materials from the interaction-so-far, the mentionables they bring to interaction, and the situated environment itself. Comparing these alternatives, there’s suggestive quantitative evidence for a preference for continuation. The analysis of lapse resolution shows lapses as places for the management of multiple possible courses of action. Data are in U.S. and UK English.

Abstract

Interaction includes moments of silence. When all participants forgo the option to speak, the silence can be called a “lapse.” This article builds on existing work on lapses and other kinds of silences (gaps, pauses, and so on) to examine how participants reach a point where lapsing is a possibility and how they orient to the lapse that subsequently develops. Drawing from a wide range of activities and settings, I will show that participants may treat lapses as (a) the relevant cessation of talk, (b) the allowable development of silence, or (c) the conspicuous absence of talk. Data are in American and British English.

Abstract

Participants in interaction routinely orient to gaze, bodily comportment, and nonlexical vocalizations as salient for developing an analysis of the unfolding course of action. In this article, I address the respiratory phenomenon of sighing, the aim being to describe sighing as a situated practice that contributes to the achievement of particular actions in interaction. I report on the various actions sighs implement or construct and how their positioning and delivery informs participants’ understandings of their significance for interaction. Data are in American English

Abstract

Background: Individuals with autism spectrum disorder (ASD) and their parents demonstrate impaired performance in rapid automatized naming (RAN), a task that recruits a variety of linguistic and executive processes. Though the basic processes that contribute to RAN differences remain unclear, eye-voice relationships, as measured through eye tracking, can provide insight into cognitive and perceptual processes contributing to RAN performance. For example, in RAN, eye-voice span (EVS), the distance ahead the eyes are when articulation of a target item's label begins, is an indirect measure of automaticity of the processes underlying RAN. The primary objective of this study was to investigate automaticity in naming processes, as indexed by EVS during RAN. The secondary objective was to characterize RAN difficulties in individuals with ASD and their siblings. Methods: Participants (aged 15 – 33 years) included 21 individuals with ASD, 23 siblings of individuals with ASD, and 24 control subjects, group-matched on chronological age. Naming time, frequency of errors, and EVS were measured during a RAN task and compared across groups. Results: A stepwise pattern of RAN performance was observed, with individuals with ASD demonstrating the slowest naming across all RAN conditions, controls demonstrating the fastest naming, and siblings demonstrating intermediate performance. Individuals with ASD exhibited smaller EVSs than controls on all RAN conditions, and siblings exhibited smaller EVSs during number naming (the most highly automatized type of naming). EVSs were correlated with naming times in controls only, and only in the more automatized conditions. Conclusions: These results suggest that reduced automaticity in the component processes of RAN may underpin differences in individuals with ASD and their siblings. These findings also provide further support that RAN abilities are impacted by genetic liability to ASD. This study has important implications for understanding the underlying skills contributing to language-related deficits in ASD.

Abstract

Recipients process information from speech and co-speech gestures, but it is currently unknown how this processing is influenced by the presence of other important social cues, especially gaze direction, a marker of communicative intent. Such cues may modulate neural activity in regions associated either with the processing of ostensive cues, such as eye gaze, or with the processing of semantic information, provided by speech and gesture.
Participants were scanned (fMRI) while taking part in triadic communication involving two recipients and a speaker. The speaker uttered sentences that
were and were not accompanied by complementary iconic gestures. Crucially, the speaker alternated her gaze direction, thus creating two recipient roles: addressed (direct gaze) vs unaddressed (averted gaze) recipient. The comprehension of Speech&Gesture relative to SpeechOnly utterances recruited middle occipital, middle temporal and inferior frontal gyri, bilaterally. The calcarine sulcus and posterior cingulate cortex were sensitive to differences between direct and averted gaze. Most importantly, Speech&Gesture utterances, but not SpeechOnly utterances, produced additional activity in the right middle temporal gyrus when participants were addressed. Marking communicative intent with gaze direction modulates the processing of speech–gesture utterances in cerebral areas typically associated with the semantic processing of multi-modal communicative acts.

Abstract

The home of human language use is face-to-face interaction, a context in which communicative exchanges are characterised not only by bodily signals accompanying what is being said but also by a pattern of alternating turns at talk. This transition between turns is astonishingly fast—typically a mere 200-ms elapse between a current and a next speaker’s contribution—meaning that comprehending, producing, and coordinating conversational contributions in time is a significant challenge. This begs the question of whether the additional information carried by bodily signals facilitates or hinders language processing in this time-pressured environment. We present analyses of multimodal conversations revealing that bodily signals appear to profoundly influence language processing in interaction: Questions accompanied by gestures lead to shorter turn transition times—that is, to faster responses—than questions without gestures, and responses come earlier when gestures end before compared to after the question turn has ended. These findings hold even after taking into account prosodic patterns and other visual signals, such as gaze. The empirical findings presented here provide a first glimpse of the role of the body in the psycholinguistic processes underpinning human communication

Abstract

In human face-to-face communication, language comprehension is a multi-modal, situated activity. However, little is known about how we combine information from different modalities during comprehension, and how perceived communicative intentions, often signaled through visual signals, influence this process. We explored this question by simulating a multi-party communication context in which a speaker alternated her gaze between two recipients. Participants viewed speech-only or speech + gesture object-related messages when being addressed (direct gaze) or unaddressed (gaze averted to other participant). They were then asked to choose which of two object images matched the speaker’s preceding message. Unaddressed recipients responded significantly more slowly than addressees for speech-only utterances. However, perceiving the same speech accompanied by gestures sped unaddressed recipients up to a level identical to that of addressees. That is, when unaddressed recipients’ speech processing suffers, gestures can enhance the comprehension of a speaker’s message. We discuss our findings with respect to two hypotheses attempting to account for how social eye gaze may modulate multi-modal language comprehension.

Abstract

One of the most intriguing aspects of human communication is its turn-taking system. It requires the ability to process on-going turns at talk while planning the next, and to launch this next turn without considerable overlap or delay. Recent research has investigated the eye movements of observers of dialogues to gain insight into how we process turns at talk. More specifically, this research has focused on the extent to which we are able to anticipate the end of current and the beginning of next turns. At the same time, there has been a call for shifting experimental paradigms exploring social-cognitive processes away from passive observation towards online processing. Here, we present research that responds to this call by situating state-of-the-art technology for tracking interlocutors’ eye movements within spontaneous, face-to-face conversation. Each conversation involved three native speakers of English. The analysis focused on question-response sequences involving just two of those participants, thus rendering the third momentarily unaddressed. Temporal analyses of the unaddressed participants’ gaze shifts from current to next speaker revealed that unaddressed participants are able to anticipate next turns, and moreover, that they often shift their gaze towards the next speaker before the current turn ends. However, an analysis of the complex structure of turns at talk revealed that the planning of these gaze shifts virtually coincides with the points at which the turns first become recog-nizable as possibly complete. We argue that the timing of these eye movements is governed by an organizational principle whereby unaddressed participants shift their gaze at a point that appears interactionally most optimal: It provides unaddressed participants with access to much of the visual, bodily behavior that accompanies both the current speaker’s and the next speaker’s turn, and it allows them to display recipiency with regard to both speakers’ turns.

Abstract

In face-to-face communication, recurring intervals of mutual gaze allow listeners to provide speakers with visual feedback (e.g. nodding). Here, we investigate the potential feedback function of one of the subtlest of human movements—eye blinking. While blinking tends to be subliminal, the significance of mutual gaze in human interaction raises the question whether the interruption of mutual gaze through blinking may also be communicative. To answer this question, we developed a novel, virtual reality-based experimental paradigm, which enabled us to selectively manipulate blinking in a virtual listener, creating small differences in blink duration resulting in ‘short’ (208 ms) and ‘long’ (607 ms) blinks. We found that speakers unconsciously took into account the subtle differences in listeners’ blink duration, producing substantially shorter answers in response to long listener blinks. Our findings suggest that, in addition to physiological, perceptual and cognitive functions, listener blinks are also perceived as communicative signals, directly influencing speakers’ communicative behavior in face-to-face communication. More generally, these findings may be interpreted as shedding new light on the evolutionary origins of mental-state signaling, which is a crucial ingredient for achieving mutual understanding in everyday social interaction.

Abstract

The FOXP2 transcription factor is one of the most well-known genes to have been implicated in developmental speech and language disorders. Rare mutations disrupting the function of this gene have been described in different families and cases. In a large three-generation family carrying a missense mutation, neuroimaging studies revealed significant effects on brain structure and function, most notably in the inferior frontal gyrus, caudate nucleus and cerebellum. After the identification of rare disruptive FOXP2 variants impacting on brain structure, several reports proposed that common variants at this locus may also have detectable effects on the brain, extending beyond disorder into normal phenotypic variation. These neuroimaging genetics studies used groups of between 14 and 96 participants. The current study assessed effects of common FOXP2 variants on neuroanatomy using voxel-based morphometry and volumetric techniques in a sample of >1300 people from the general population. In a first targeted stage we analyzed single nucleotide polymorphisms (SNPs) claimed to have effects in prior smaller studies (rs2253478, rs12533005, rs2396753, rs6980093, rs7784315, rs17137124, rs10230558, rs7782412, rs1456031), beginning with regions proposed in the relevant papers, then assessing impact across the entire brain. In the second gene-wide stage, we tested all common FOXP2 variation, focusing on volumetry of those regions most strongly implicated from analyses of rare disruptive mutations. Despite using a sample that is more than ten times that used for prior studies of common FOXP2 variation, we found no evidence for effects of SNPs on variability in neuroanatomy in the general population. Thus, the impact of this gene on brain structure may be largely limited to extreme cases of rare disruptive alleles. Alternatively, effects of common variants at this gene exist but are too subtle to be detected with standard volumetric techniques

Abstract

Here, we report evidence for oscillatory bi-directional interactions between the nucleus accumbens and the neocortex in humans. Six patients performed a demanding covert visual attention task while we simultaneously recorded brain activity from deep-brain electrodes implanted in the nucleus accumbens and the surface electroencephalogram (EEG). Both theta and alpha oscillations were strongly coherent with the frontal and parietal EEG during the task. Theta-band coherence increased during processing of the visual stimuli. Granger causality analysis revealed that the nucleus accumbens was communicating with the neocortex primarily in the theta-band, while the cortex was communicating the nucleus accumbens in the alpha-band. These data are consistent with a model, in which theta- and alpha-band oscillations serve dissociable roles: Prior to stimulus processing, the cortex might suppress ongoing processing in the nucleus accumbens by modulating alpha-band activity. Subsequently, upon stimulus presentation, theta oscillations might facilitate the active exchange of stimulus information from the nucleus accumbens to the cortex.