Publications

Abstract

The lexical and phonetic mapping of auditorily confusable L2 nonwords was examined by teaching L2 learners novel words and by later examining their word recognition using an eye-tracking paradigm. During word learning, two groups of highly proficient Dutch learners of English learned 20 English nonwords, of which 10 contained the English contrast /e/-æ/ (a confusable contrast for native Dutch speakers). One group of subjects learned the words by matching their auditory forms to pictured meanings, while a second group additionally saw the spelled forms of the words. We found that the group who received only auditory forms confused words containing /æ/ and /e/ symmetrically, i.e., both /æ/ and /e/ auditory tokens triggered looks to pictures containing both /æ/ and /e/. In contrast, the group who also had access to spelled forms showed the same asymmetric word recognition pattern found by previous studies, i.e., they only looked at pictures of words containing /e/ when presented with /e/ target tokens, but looked at pictures of words containing both /æ/ and /e/ when presented with /æ/ target tokens. The results demonstrate that L2 learners can form lexical contrasts for auditorily confusable novel L2 words. However, and most importantly, this study suggests that explicit information over the contrastive nature of two new sounds may be needed to build separate lexical representations for similar-sounding L2 words.

Abstract

This paper compares “cut” and “break” verbs in four variants of Gbe, namely Anfoe, Anlo, Fon and Ayizo, with those of Sranan. “Cut” verbs are change-of-state verbs that co-lexicalize the type of action that brings about a change, the type of instrument or instrument part, and the manner in which a change occurs. By contrast, break verbs co-lexicalize either the type of object or the type of change. It has been hypothesized that “cut”-verbs are unergative while breaks verbs are unaccusatives. For example “break” verbs participate in the causative alternation constructions but “cut” verbs don’t. We show that although there are some differences in the meanings of “cut” and break verbs across the Gbe languages, significant generalizations can be made with regard to their lexicalization patterns. By contrast, the meanings of “cut” and break verbs in Sranan are closer to those of their etymons in English and Dutch. However, despite the differences in the meanings of “cut” and “break” verbs between the Gbe languages and Sranan, the syntax of the verbs in Sranan is similar to that of the Eastern Gbe variants, namely Fon and Ayizo. We look at the implications of our findings for the relexification hypothesis. (copyright Benjamins)

Abstract

Studies of the impact of brain injury on memory processes often focus on the quantity and episodic richness of those recollections. Here, we argue that the organization of one's recollections offers critical insights into the impact of brain injury on functional memory. It is well-established in studies of word list memory that free recall of unrelated words exhibits a clear temporal organization. This temporal contiguity effect refers to the fact that the order in which word lists are recalled reflects the original presentation order. Little is known, however, about the organization of recall for semantically rich materials, nor how recall organization is impacted by hippocampal damage and memory impairment. The present research is the first study, to our knowledge, of temporal organization in semantically rich narratives in three groups: (1) Adults with bilateral hippocampal damage and severe declarative memory impairment, (2) adults with bilateral ventromedial prefrontal cortex (vmPFC) damage and no memory impairment, and (3) demographically matched non-brain-injured comparison participants. We find that although the narrative recall of adults with bilateral hippocampal damage reflected the temporal order in which those narratives were experienced above chance levels, their temporal contiguity effect was significantly attenuated relative to comparison groups. In contrast, individuals with vmPFC damage did not differ from non-brain-injured comparison participants in temporal contiguity. This pattern of group differences yields insights into the cognitive and neural systems that support the use of temporal organization in recall. These data provide evidence that the retrieval of temporal context in narrative recall is hippocampal-dependent, whereas damage to the vmPFC does not impair the temporal organization of narrative recall. This evidence of limited but demonstrable organization of memory in participants with hippocampal damage and amnesia speaks to the power of narrative structures in supporting meaningfully organized recall despite memory impairment.

Abstract

A principal components analysis of the ten scales of the Worry Questionnaire revealed the existence of major worry factors or domains of social evaluation and physical threat, and these factors were confirmed in a subsequent item analysis. Those high in trait anxiety had much higher scores on the Worry Questionnaire than those low in trait anxiety, especially on those scales relating to social evaluation. Scores on the Marlowe-Crowne Social Desirability Scale were negatively related to worry frequency. However, groups of low-anxious and repressed individucores did not differ in worry. It was concluded that worry, especals formed on the basis of their trait anxiety and social desirability sially in the social evaluation domain, is of fundamental importance to trait anxiety.

Abstract

Deficits in phonological short-term memory and aspects of verb grammar morphology have been proposed as phenotypic markers of specific language impairment (SLI) with the suggestion that these traits are likely to be under different genetic influences. This investigation in 300 first-degree relatives of 93 probands with SLI examined familial aggregation and genetic linkage of two measures thought to index these two traits, non-word repetition and tense marking. In particular, the involvement of chromosomes 16q and 19q was examined as previous studies found these two regions to be related to SLI. Results showed a strong association between relatives' and probands' scores on non-word repetition. In contrast, no association was found for tense marking when examined as a continuous measure. However, significant familial aggregation was found when tense marking was treated as a binary measure with a cut-off point of -1.5 SD, suggestive of the possibility that qualitative distinctions in the trait may be familial while quantitative variability may be more a consequence of non-familial factors. Linkage analyses supported previous findings of the SLI Consortium of linkage to chromosome 16q for phonological short-term memory and to chromosome 19q for expressive language. In addition, we report new findings that relate to the past tense phenotype. For the continuous measure, linkage was found on both chromosomes, but evidence was stronger on chromosome 19. For the binary measure, linkage was observed on chromosome 19 but not on chromosome 16.

Abstract

The value of normative models in research and clinical practice relies on their robustness and a systematic comparison of different modelling algorithms and parameters; however, this has not been done to date. We aimed to identify the optimal approach for normative modelling of brain morphometric data through systematic empirical benchmarking, by quantifying the accuracy of different algorithms and identifying parameters that optimised model performance. We developed this framework with regional morphometric data from 37 407 healthy individuals (53% female and 47% male; aged 3–90 years) from 87 datasets from Europe, Australia, the USA, South Africa, and east Asia following a comparative evaluation of eight algorithms and multiple covariate combinations pertaining to image acquisition and quality, parcellation software versions, global neuroimaging measures, and longitudinal stability. The multivariate fractional polynomial regression (MFPR) emerged as the preferred algorithm, optimised with non-linear polynomials for age and linear effects of global measures as covariates. The MFPR models showed excellent accuracy across the lifespan and within distinct age-bins and longitudinal stability over a 2-year period. The performance of all MFPR models plateaued at sample sizes exceeding 3000 study participants. This model can inform about the biological and behavioural implications of deviations from typical age-related neuroanatomical changes and support future study designs. The model and scripts described here are freely available through CentileBrain.

Abstract

The oldest of the Celtic language family, Irish differs considerably from English, notably with respect to word order and case marking. In spite of differences in surface constituent structure, less restricted accounts of bilingual shared syntax predict that processing datives and passives in Irish should prime the production of their English equivalents. Furthermore, this cross-linguistic influence should be sensitive to L2 proficiency, if shared structural representations are assumed to develop over time. In Experiment 1, we investigated cross-linguistic structural priming from Irish to English in 47 bilingual adolescents who are educated through Irish. Testing took place in a classroom setting, using written primes and written sentence generation. We found that priming for prepositional-object (PO) datives was predicted by self-rated Irish (L2) proficiency, in line with previous studies. In Experiment 2, we presented translations of the materials to an English-educated control group (n=54). We found a within-language priming effect for PO datives, which was not modulated by English (L1) proficiency. Our findings are compatible with current theories of bilingual language processing and L2 syntactic acquisition.

Abstract

When speaking in any language, speakers must conceptualize what they want to say before they can formulate and articulate their message. We present two experiments employing a novel experimental paradigm in which the formulating and articulating stages of speech production were kept identical across conditions of differing conceptualizing difficulty. We tracked the effect of difficulty in conceptualizing during the generation of speech (Experiment 1) and during the abandonment and regeneration of speech (Experiment 2) on speaking fluency by Dutch native speakers in their first (L1) and second (L2) language (English). The results showed that abandoning and especially regenerating a speech plan taxes the speaker, leading to disfluencies. For most fluency measures, the increases in disfluency were similar across L1 and L2. However, a significant interaction revealed that abandoning and regenerating a speech plan increases the time needed to solve conceptual difficulties while speaking in the L2 to a greater degree than in the L1. This finding supports theories in which cognitive resources for conceptualizing are shared with those used for later stages of speech planning. Furthermore, a practical implication for language assessment is that increasing the conceptual difficulty of speaking tasks should be considered with caution.

Abstract

This study investigates the real-time processing of wh-dependencies by advanced Greek-speaking learners of English using a cross-modal picture priming task. Participants were asked to respond to different types of picture target presented either at structurally defined gap positions, or at pre-gap control positions, while listening to sentences containing indirect-object relative clauses. Our results indicate that the learners processed the experimental sentences differently from both adult native speakers of English and monolingual English-speaking children. Contrary to what has been found for native speakers, the learners' response pattern was not influenced by individual working memory differences. Adult second language learners differed from native speakers with a relatively high reading or listening span in that they did not show any evidence of structurally based antecedent reactivation at the point of the indirect object gap. They also differed from low-span native speakers, however, in that they showed evidence of maintained antecedent activation during the processing of the experimental sentences. Whereas the localized priming effect observed in the high-span controls is indicative of trace-based antecedent reactivation in native sentence processing, the results from the Greek-speaking learners support the hypothesis that the mental representations built during non-native language processing lack abstract linguistic structure such as movement traces.

Abstract

A large literature in social neuroscience has associated the medial prefrontal cortex (mPFC) with the processing of self-related information. However, only recently have social neuroscience studies begun to consider the large behavioral literature showing a strong self-positivity bias, and these studies have mostly focused on its correlates during self-related judgments and decision making. We carried out a functional MRI (fMRI) study to ask whether the mPFC would show effects of the self-positivity bias in a paradigm that probed participants’ self-concept without any requirement of explicit self-judgment. We presented social vignettes that were either self-relevant or non-self-relevant with a neutral, positive, or negative outcome described in the second sentence. In previous work using event-related potentials, this paradigm has shown evidence of a self-positivity bias that influences early stages of semantically processing incoming stimuli. In the present fMRI study, we found evidence for this bias within the mPFC: an interaction between self-relevance and valence, with only positive scenarios showing a self vs other effect within the mPFC. We suggest that the mPFC may play a role in maintaining a positively-biased self-concept and discuss the implications of these findings for the social neuroscience of the self and the role of the mPFC.

Abstract

FOXP2 mutations cause a speech and language disorder, raising interest in potential roles of this gene in human evolution. A new study re-evaluates genomic variation at the human FOXP2 locus but finds no evidence of recent adaptive evolution.

Abstract

Why do some children fail to acquire speech and language skills despite adequate environmental input and overtly normal neurological and anatomical development? It has been suspected for several decades, based on indirect evidence, that the human genome might hold some answers to this enigma. These suspicions have recently received dramatic confirmation with the discovery of specific genetic changes which appear sufficient to derail speech and language development. Indeed, researchers are already using information from genetic studies to aid early diagnosis and to shed light on the neural pathways that are perturbed in these inherited forms of speech and language disorder. Thus, we have entered an exciting era for dissecting the neural bases of human communication, one which takes genes and molecules as a starting point. In the current article I explain how this recent paradigm shift has occurred and describe the new vistas that have opened up. I demonstrate ways of bridging the gaps between molecules, neurons and the brain, which will provide a new understanding of the aetiology of speech and language impairments.

Abstract

Event-related potentials (ERPs) provide a window into how the brain is processing language. Here, we propose a theory that argues that ERPs such as the N400 and P600 arise as side effects of an error-based learning mechanism that explains linguistic adaptation and language learning. We instantiated this theory in a connectionist model that can simulate data from three studies on the N400 (amplitude modulation by expectancy, contextual constraint, and sentence position), five studies on the P600 (agreement, tense, word category, subcategorization and garden-path sentences), and a study on the semantic P600 in role reversal anomalies. Since ERPs are learning signals, this account explains adaptation of ERP amplitude to within-experiment frequency manipulations and the way ERP effects are shaped by word predictability in earlier sentences. Moreover, it predicts that ERPs can change over language development. The model provides an account of the sensitivity of ERPs to expectation mismatch, the relative timing of the N400 and P600, the semantic nature of the N400, the syntactic nature of the P600, and the fact that ERPs can change with experience. This approach suggests that comprehension ERPs are related to sentence production and language acquisition mechanisms

Abstract

The language faculty is physically realized in the neurobiological infrastructure of the human brain. Despite significant efforts, an integrated understanding of this system remains a formidable challenge. What is missing from most theoretical accounts is a specification of the neural mechanisms that implement language function. Computational models that have been put forward generally lack an explicit neurobiological foundation. We propose a neurobiologically informed causal modeling approach which offers a framework for how to bridge this gap. A neurobiological causal model is a mechanistic description of language processing that is grounded in, and constrained by, the characteristics of the neurobiological substrate. It intends to model the generators of language behavior at the level of implementational causality. We describe key features and neurobiological component parts from which causal models can be built and provide guidelines on how to implement them in model simulations. Then we outline how this approach can shed new light on the core computational machinery for language, the long-term storage of words in the mental lexicon and combinatorial processing in sentence comprehension. In contrast to cognitive theories of behavior, causal models are formulated in the “machine language” of neurobiology which is universal to human cognition. We argue that neurobiological causal modeling should be pursued in addition to existing approaches. Eventually, this approach will allow us to develop an explicit computational neurobiology of language.

Abstract

Electrophysiological studies consistently find N400 effects of semantic incongruity in non-native written language comprehension. Typically these N400 effects are later than N400 effects in native comprehension, suggesting that semantic processing in one’s second language (L2) may be delayed compared to one’s first language (L1). In this study we were firstly interested in replicating the semantic incongruity effect using natural auditory speech, which poses strong demands on the speed of processing. Secondly, we wished to investigate whether a possible delay in semantic processing might be due to bilinguals accessing lexical items from both their L1 and L2 (a more extensive lexical search). We recorded EEG from 30 Dutch-English bilinguals who listened to English sentences � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � ��� � � in which the sentence-final word was: (1) semantically fitting, (2) semantically incongruent, (3) initially congruent: semantically incongruent, but sharing initial phonemes with the most probable sentence completion within the L2, (4) semantically incongruent, but sharing initial phonemes with the L1 translation equivalent of the most probable sentence completion. We found an N400 effect in each of the semantically incongruent conditions. This N400 effect was significantly delayed to L2 words that were initially congruent with the sentence context. We found no effect of initial overlap with L1 translation equivalents. Taken together these findings firstly demonstrate that non-native listeners are sensitive to semantic incongruity in natural speech, secondly indicate that semantic integration in non-native listening can start on the basis of word initial phonemes, and finally suggest that during L2 sentence processing listeners do not access the L1 lexicon.

Abstract

Partway along the vast waterways of Brazil's middle Rio Negro, upstream from urban Manaus and downstream from the ethnographically famous Northwest Amazon region, is the town of Castanheiro, whose inhabitants skillfully negotiate a space between the polar extremes of 'traditional' and 'acculturated.' This paper takes an ethnographic look at the non-polarizing terms that these rural Amazonian people use for talking about cultural change. While popular and academic discourses alike have often framed cultural change in the Amazon as a linear process, Amazonian discourse provides resources for describing change as situated in shifting fields of knowledge of the social and physical environments, better capturing its non-linear complexity and ambiguity.

Abstract

This paper gives an account of the pirate media economy of Ecuador and its role in the emergence of indigenous Quichua-language media spaces, identifying the different parties involved in this economy, discussing their relationship to the parallel ‘‘legitimate’’ media economy, and considering the implications of this informal media market for Quichua linguistic and cultural reproduction. As digital recording and playback technology has become increasingly more affordable and widespread over recent years, black markets have grown up worldwide, based on cheap ‘‘illegal’’ reproduction of commercial media, today sold by informal entrepreneurs in rural markets, shops and street corners around Ecuador. Piggybacking on this pirate infrastructure, Quichua-speaking media producers and consumers have begun to circulate indigenous-language video at an unprecedented rate, helped by small-scale merchants who themselves profit by supplying market demands for positive images of indigenous people. In a context of a national media that has tended to silence indigenous voices rather than amplify them, informal media producers, consumers and vendors are developing relationships that open meaningful media spaces within the particular social, economic and linguistic contexts of Ecuador.

Abstract

Several studies have reported an association between dyslexia and implicit learning deficits. It has been suggested that the weakness in implicit learning observed in dyslexic individuals may be related to sequential processing and implicit sequence learning. In the present article, we review the current literature on implicit learning and dyslexia. We describe a novel, forced-choice structural "mere exposure" artificial grammar learning paradigm and characterize this paradigm in normal readers in relation to the standard grammaticality classification paradigm. We argue that preference classification is a more optimal measure of the outcome of implicit acquisition since in the preference version participants are kept completely unaware of the underlying generative mechanism, while in the grammaticality version, the subjects have, at least in principle, been informed about the existence of an underlying complex set of rules at the point of classification (but not during acquisition). On the basis of the "mere exposure effect," we tested the prediction that the development of preference will correlate with the grammaticality status of the classification items. In addition, we examined the effects of grammaticality (grammatical/nongrammatical) and associative chunk strength (ACS; high/low) on the classification tasks (preference/grammaticality). Using a balanced ACS design in which the factors of grammaticality (grammatical/nongrammatical) and ACS (high/low) were independently controlled in a 2 × 2 factorial design, we confirmed our predictions. We discuss the suitability of this task for further investigation of the implicit learning characteristics in dyslexia.

Abstract

Human implicit learning can be investigated with implicit artificial grammar learning, a paradigm that has been proposed as a simple model for aspects of natural language acquisition. In the present study we compared the typical yes–no grammaticality classification, with yes–no preference classification. In the case of preference instruction no reference to the underlying generative mechanism (i.e., grammar) is needed and the subjects are therefore completely uninformed about an underlying structure in the acquisition material. In experiment 1, subjects engaged in a short-term memory task using only grammatical strings without performance feedback for 5 days. As a result of the 5 acquisition days, classification performance was independent of instruction type and both the preference and the grammaticality group acquired relevant knowledge of the underlying generative mechanism to a similar degree. Changing the grammatical stings to random strings in the acquisition material (experiment 2) resulted in classification being driven by local substring familiarity. Contrasting repeated vs. non-repeated preference classification (experiment 3) showed that the effect of local substring familiarity decreases with repeated classification. This was not the case for repeated grammaticality classifications. We conclude that classification performance is largely independent of instruction type and that forced-choice preference classification is equivalent to the typical grammaticality classification.

Abstract

Traditionally, language processing has been thought of in terms of complete processing of the input. In contrast to this, Ferreira and colleagues put forth the idea of good enough processing. The proposal was that during everyday processing, ambiguities remain unresolved, we rely on heuristics instead of full analyses, and we carry out deep processing only if we need to for the task at hand. This idea has gathered substantial traction since its conception. In the current work, I review the papers that have tested the three key claims of good enough processing: ambiguities remain unresolved and underspecified, we use heuristics to parse sentences, and deep processing is only carried out if required by the task. I find mixed evidence for these claims and conclude with an appeal to further refinement of the claims and predictions of the theory.

Abstract

Earlier work has explored spoken word production during irrelevant background speech such as intelligible and unintelligible word lists. The present study compared how different types of irrelevant background speech (word lists vs. sentences) influenced spoken word production relative to a quiet control condition, and whether the influence depended on the intelligibility of the background speech. Experiment 1 presented native Dutch speakers with Chinese word lists and sentences. Experiment 2 presented a similar group with Dutch word lists and sentences. In both experiments, the lexical selection demands in speech production were manipulated by varying name agreement (high vs. low) of the to-be-named pictures. Results showed that background speech, regardless of its intelligibility, disrupted spoken word production relative to a quiet condition, but no effects of word lists versus sentences in either language were found. Moreover, the disruption by intelligible background speech compared with the quiet condition was eliminated when planning low name agreement pictures. These findings suggest that any speech, even unintelligible speech, interferes with production, which implies that the disruption of spoken word production is mainly phonological in nature. The disruption by intelligible background speech can be reduced or eliminated via top–down attentional engagement.

Abstract

Family and twin studies consistently demonstrate a significant role for genetic factors in the aetiology of the reading disorder dyslexia. However, dyslexia is complex at both the genetic and phenotypic levels, and currently the nature of the core deficit or deficits remains uncertain. Traditional approaches for mapping disease genes, originally developed for single-gene disorders, have limited success when there is not a simple relationship between genotype and phenotype. Recent advances in high-throughput genotyping technology and quantitative statistical methods have made a new approach to identifying genes involved in complex disorders possible. The method involves assessing the genetic similarity of many sibling pairs along the lengths of all their chromosomes and attempting to correlate this similarity with that of their phenotypic scores. We are adopting this approach in an ongoing genome-wide search for genes involved in dyslexia susceptibility, and have already successfully applied the method by replicating results from previous studies suggesting that a quantitative trait locus at 6p21.3 influences reading disability.

Abstract

Left-right asymmetrical brain function underlies much of human cognition, behavior and emotion. Abnormalities of cerebral asymmetry are associated with schizophrenia and other neuropsychiatric disorders. The molecular, developmental and evolutionary origins of human brain asymmetry are unknown. We found significant association of a haplotype upstream of the gene LRRTM1 (Leucine-rich repeat transmembrane neuronal 1) with a quantitative measure of human handedness in a set of dyslexic siblings, when the haplotype was inherited paternally (P=0.00002). While we were unable to find this effect in an epidemiological set of twin-based sibships, we did find that the same haplotype is overtransmitted paternally to individuals with schizophrenia/schizoaffective disorder in a study of 1002 affected families (P=0.0014). We then found direct confirmatory evidence that LRRTM1 is an imprinted gene in humans that shows a variable pattern of maternal downregulation. We also showed that LRRTM1 is expressed during the development of specific forebrain structures, and thus could influence neuronal differentiation and connectivity. This is the first potential genetic influence on human handedness to be identified, and the first putative genetic effect on variability in human brain asymmetry. LRRTM1 is a candidate gene for involvement in several common neurodevelopmental disorders, and may have played a role in human cognitive and behavioral evolution.

Abstract

Because higher level cognitive processes generally involve the use of world knowledge, computational models of these processes require the implementation of a knowledge base. This article identifies and discusses 4 strategies for dealing with world knowledge in computational models: disregarding world knowledge, ad hoc selection, extraction from text corpora, and implementation of all knowledge about a simplified microworld. Each of these strategies is illustrated by a detailed discussion of a model of discourse comprehension. It is argued that seemingly successful modeling results are uninformative if knowledge is implemented ad hoc or not at all, that knowledge extracted from large text corpora is not appropriate for discourse comprehension, and that a suitable implementation can be obtained by applying the microworld strategy.

Abstract

We present a computational model that provides a unified account of inference, coherence, and disambiguation. It simulates how the build-up of coherence in text leads to the knowledge-based resolution of referential ambiguity. Possible interpretations of an ambiguity are represented by centers of gravity in a high-dimensional space. The unresolved ambiguity forms a vector in the same space. This vector is attracted by the centers of gravity, while also being affected by context information and world knowledge. When the vector reaches one of the centers of gravity, the ambiguity is resolved to the corresponding interpretation. The model accounts for reading time and error rate data from experiments on ambiguous pronoun resolution and explains the effects of context informativeness, anaphor type, and processing depth. It shows how implicit causality can have an early effect during reading. A novel prediction is that ambiguities can remain unresolved if there is insufficient disambiguating information.

Abstract

ADHD is a neuropsychiatric disorder characterized by chronic hyperactivity, inattention and impulsivity, which affects about 5% of school-age children. ADHD persists into adulthood in at least 15% of cases. It is highly heritable and familial influences seem strongest for ADHD persisting into adulthood. However, most of the genetic research in ADHD has been carried out in children with the disorder. The gene that has received most attention in ADHD genetics is SLC6A3/DAT1 encoding the dopamine transporter. In the current study we attempted to replicate in adults with ADHD the reported association of a 10–6 SLC6A3-haplotype, formed by the 10-repeat allele of the variable number of tandem repeat (VNTR) polymorphism in the 3′ untranslated region of the gene and the 6-repeat allele of the VNTR in intron 8 of the gene, with childhood ADHD. In addition, we wished to explore the role of a recently described VNTR in intron 3 of the gene. Two hundred sixteen patients and 528 controls were included in the study. We found a 9–6 SLC6A3-haplotype, rather than the 10–6 haplotype, to be associated with ADHD in adults. The intron 3 VNTR showed no association with adult ADHD. Our findings converge with earlier reports and suggest that age is an important factor to be taken into account when assessing the association of SLC6A3 with ADHD. If confirmed in other studies, the differential association of the gene with ADHD in children and in adults might imply that SLC6A3 plays a role in modulating the ADHD phenotype, rather than causing it

Abstract

Previous research on the effect of perturbed auditory feedback in speech production has focused on two types of responses. In the short term, speakers generate compensatory motor commands in response to unexpected perturbations. In the longer term, speakers adapt feedforward motor programmes in response to feedback perturbations, to avoid future errors. The current study investigated the relation between these two types of responses to altered auditory feedback. Specifically, it was hypothesised that consistency in previous feedback perturbations would influence whether speakers adapt their feedforward motor programmes. In an altered auditory feedback paradigm, formant perturbations were applied either across all trials (the consistent condition) or only to some trials, whereas the others remained unperturbed (the inconsistent condition). The results showed that speakers’ responses were affected by feedback consistency, with stronger speech changes in the consistent condition compared with the inconsistent condition. Current models of speech-motor control can explain this consistency effect. However, the data also suggest that compensation and adaptation are distinct processes, which are not in line with all current models.

Abstract

Kleefstra syndrome (KS) is a neurodevelopmental disorder caused by mutations in the histone methyltransferase EHMT1. To study the impact of decreased EHMT1 function in human cells, we generated excitatory cortical neurons from induced pluripotent stem (iPS) cells derived from KS patients. Neuronal networks of patient-derived cells exhibit network bursting with a reduced rate, longer duration, and increased temporal irregularity compared to control networks. We show that these changes are mediated by upregulation of NMDA receptor (NMDAR) subunit 1 correlating with reduced deposition of the repressive H3K9me2 mark, the catalytic product of EHMT1, at the GRIN1 promoter. In mice EHMT1 deficiency leads to similar neuronal network impairments with increased NMDAR function. Finally, we rescue the KS patient-derived neuronal network phenotypes by pharmacological inhibition of NMDARs. Summarized, we demonstrate a direct link between EHMT1 deficiency and NMDAR hyperfunction in human neurons, providing a potential basis for more targeted therapeutic approaches for KS.

Abstract

Disruptions of the FOXP2 gene cause a speech and language disorder involving difficulties in sequencing orofacial movements. FOXP2 is expressed in cortico-striatal and cortico-cerebellar circuits important for fine motor skills, and affected individuals show abnormalities in these brain regions. We selectively disrupted Foxp2 in the cerebellar Purkinje cells, striatum or cortex of mice and assessed the effects on skilled motor behaviour using an operant lever-pressing task. Foxp2 loss in each region impacted behaviour differently, with striatal and Purkinje cell disruptions affecting the variability and the speed of lever-press sequences, respectively. Mice lacking Foxp2 in Purkinje cells showed a prominent phenotype involving slowed lever pressing as well as deficits in skilled locomotion. In vivo recordings from Purkinje cells uncovered an increased simple spike firing rate and decreased modulation of firing during limb movements. This was caused by increased intrinsic excitability rather than changes in excitatory or inhibitory inputs. Our findings show that Foxp2 can modulate different aspects of motor behaviour in distinct brain regions, and uncover an unknown role for Foxp2 in the modulation of Purkinje cell activity that severely impacts skilled movements.

Abstract

Disruptions of the human FOXP2 gene cause problems with articulation of complex speech sounds, accompanied by impairment in many aspects of language ability. The FOXP2/Foxp2 transcription factor is highly similar in humans and mice, and shows a complex conserved expression pattern, with high levels in neuronal subpopulations of the cortex, striatum, thalamus, and cerebellum. In the present study we generated mice in which loxP sites flank exons 12-14 of Foxp2; these exons encode the DNA-binding motif, a key functional domain. We demonstrate that early global Cre-mediated recombination yields a null allele, as shown by loss of the loxP-flanked exons at the RNA level and an absence of Foxp2 protein. Homozygous null mice display severe motor impairment, cerebellar abnormalities and early postnatal lethality, consistent with other Foxp2 mutants. When crossed to transgenic lines expressing Cre protein in a spatially and/or temporally controlled manner, these conditional mice will provide new insights into the contributions of Foxp2 to distinct neural circuits, and allow dissection of roles during development and in the mature brain.

Abstract

High frequency words have been suggested to benefit both speech segmentation and grammatical categorization of the words around them. Despite utilizing similar information, these tasks are usually investigated separately in studies examining learning. We determined whether including high frequency words in continuous speech could support categorization when words are being segmented for the first time. We familiarized learners with continuous artificial speech comprising repetitions of target words, which were preceded by high-frequency marker words. Crucially, marker words distinguished targets into 2 distributionally defined categories. We measured learning with segmentation and categorization tests and compared performance against a control group that heard the artificial speech without these marker words (i.e., just the targets, with no cues for categorization). Participants segmented the target words from speech in both conditions, but critically when the marker words were present, they influenced acquisition of word-referent mappings in a subsequent transfer task, with participants demonstrating better early learning for mappings that were consistent (rather than inconsistent) with the distributional categories. We propose that high-frequency words may assist early grammatical categorization, while speech segmentation is still being learned.

Abstract

Discourse markers (DMs) are linguistic elements that index different relations and coherence between units of talk (Schiffrin, Deborah, 1987. Discourse Markers. Cambridge University Press, Cambridge). Most research on the development of these forms has focused on conversations rather than narratives and furthermore has not directly compared children's use of DMs to adult usage. This study examines the development of three DMs (şey ‘uuhh’, yani ‘I mean’, işte ‘y’know’) that mark interactional levels of discourse in oral Turkish narratives in 60 Turkish children (3-, 5- and 9-year-olds) and 20 Turkish-speaking adults. The results show that the frequency and functions of DMs change with age. Children learn şey, which mainly marks exchange level structures, earliest. However, yani and işte have multi-functions such as marking both information states and participation frameworks and are consequently learned later. Children also use DMs with different functions than adults. Overall, the results show that learning to use interactional DMs in narratives is complex and goes beyond age 9, especially for multi-functional DMs that index an interplay of discourse coherence at different levels.

Abstract

Several studies report an association between REM Sleep Behavior Disorder (RBD) and neurodegenerative diseases, in particular synucleinopathies. Interestingly, the onset of RBD precedes the development of neurodegeneration by several years. This review and meta-analysis aims to establish the rate of conversion of RBD into neurodegenerative diseases. Longitudinal studies were searched from the PubMed, Web of Science, and SCOPUS databases. Using random-effect modeling, we performed a meta-analysis on the rate of RBD conversions into neurodegeneration. Furthermore, we fitted a Kaplan-Meier analysis and compared the differences between survival curves of different diseases with log-rank tests. The risk for developing neurodegenerative diseases was 33.5% at five years follow-up, 82.4% at 10.5 years and 96.6% at 14 years. The average conversion rate was 31.95% after a mean duration of follow-up of 4.75 ± 2.43 years. The majority of RBD patients converted to Parkinson's Disease (43%), followed by Dementia with Lewy Bodies (25%). The estimated risk for RBD patients to develop a neurodegenerative disease over a long-term follow-up is more than 90%. Future studies should include control group for the evaluation of REM sleep without atonia as marker for neurodegeneration also in non-clinical population and target RBD as precursor of neurodegeneration to develop protective trials.

Abstract

Speakers continuously monitor what they say. Sometimes, self-monitoring malfunctions and errors pass undetected and uncorrected. In the field of action monitoring, an event-related brain potential, the error-related negativity (ERN), is associated with error processing. The present study relates the ERN to verbal self-monitoring and investigates how the ERN is affected by auditory distractors during verbal monitoring. We found that the ERN was largest following errors that occurred after semantically related distractors had been presented, as compared to semantically unrelated ones. This result demonstrates that the ERN is sensitive not only to response conflict resulting from the incompatibility of motor responses but also to more abstract lexical retrieval conflict resulting from activation of multiple lexical entries. This, in turn, suggests that the functioning of the verbal self-monitoring system during speaking is comparable to other performance monitoring, such as action monitoring.

Abstract

During speech production, we continuously monitor what we say. In
situations in which speech errors potentially have more severe
consequences, e.g. during a public presentation, our verbal selfmonitoring
system may pay special attention to prevent errors than in
situations in which speech errors are more acceptable, such as a casual
conversation. In an event-related potential study, we investigated
whether or not motivation affected participants’ performance using a
picture naming task in a semantic blocking paradigm. Semantic
context of to-be-named pictures was manipulated; blocks were
semantically related (e.g., cat, dog, horse, etc.) or semantically
unrelated (e.g., cat, table, flute, etc.). Motivation was manipulated
independently by monetary reward. The motivation manipulation did
not affect error rate during picture naming. However, the highmotivation
condition yielded increased amplitude and latency values of
the error-related negativity (ERN) compared to the low-motivation
condition, presumably indicating higher monitoring activity. Furthermore,
participants showed semantic interference effects in reaction
times and error rates. The ERN amplitude was also larger during
semantically related than unrelated blocks, presumably indicating that
semantic relatedness induces more conflict between possible verbal
responses.

Abstract

Learning to read a second language (L2) can pose a great challenge for children who have already been struggling to read in their first language (L1). Moreover, it is not clear whether, to what extent, and under what circumstances L1 reading difficulty increases the risk of L2 reading difficulty. This study investigated Chinese (L1) and English (L2) reading skills in a large representative sample of 1,824 Chinese–English bilingual children in Grades 4 and 5 from both urban and rural schools in Beijing. We examined the prevalence of reading difficulty in Chinese only (poor Chinese readers, PC), English only (poor English readers, PE), and both Chinese and English (poor bilingual readers, PB) and calculated the co-occurrence, that is, the chances of becoming a poor reader in English given that the child was already a poor reader in Chinese. We then conducted a multinomial logistic regression analysis and compared the prevalence of PC, PE, and PB between children in Grade 4 versus Grade 5, in urban versus rural areas, and in boys versus girls. Results showed that compared to girls, boys demonstrated significantly higher risk of PC, PE, and PB. Meanwhile, compared to the 5th graders, the 4th graders demonstrated significantly higher risk of PC and PB. In addition, children enrolled in the urban schools were more likely to become better second language readers, thus leading to a concerning rural–urban gap in the prevalence of L2 reading difficulty. Finally, among these Chinese–English bilingual children, regardless of sex and school location, poor reading skill in Chinese significantly increased the risk of also being a poor English reader, with a considerable and stable co-occurrence of approximately 36%. In sum, this study suggests that despite striking differences between alphabetic and logographic writing systems, L1 reading difficulty still significantly increases the risk of L2 reading difficulty. This indicates the shared meta-linguistic skills in reading different writing systems and the importance of understanding the universality and the interdependent relationship of reading between different writing systems. Furthermore, the male disadvantage (in both L1 and L2) and the urban–rural gap (in L2) found in the prevalence of reading difficulty calls for special attention to disadvantaged populations in educational practice.

Abstract

Previous research shows conflicting findings for the effect of font readability on comprehension and memory for language. It has been found that—perhaps counterintuitively–a hard to read font can be beneficial for language comprehension, especially for difficult language. Here we test how font readability influences the subjective experience of poetry reading. In three experiments we tested the influence of poem difficulty and font readability on the subjective experience of poems. We specifically predicted that font readability would have opposite effects on the subjective experience of easy versus difficult poems. Participants read poems which could be more or less difficult in terms of conceptual or structural aspects, and which were presented in a font that was either easy or more difficult to read. Participants read existing poems and subsequently rated their subjective experience (measured through four dependent variables: overall liking, perceived flow of the poem, perceived topic clarity, and perceived structure). In line with previous literature we observed a Poem Difficulty x Font Readability interaction effect for subjective measures of poetry reading. We found that participants rated easy poems as nicer when presented in an easy to read font, as compared to when presented in a hard to read font. Despite the presence of the interaction effect, we did not observe the predicted opposite effect for more difficult poems. We conclude that font readability can influence reading of easy and more difficult poems differentially, with strongest effects for easy poems.

Abstract

It is a common finding across languages that young children have problems in understanding patient-initial sentences. We used Tagalog, a verb-initial language with a reliable voice-marking system and highly frequent patient voice constructions, to test the predictions of several accounts that have been proposed to explain this difficulty: the frequency account, the Competition Model, and the incremental processing account. Study 1 presents an analysis of Tagalog child-directed speech, which showed that the dominant argument order is agent-before-patient and that morphosyntactic markers are highly valid cues to thematic role assignment. In Study 2, we used a combined self-paced listening and picture verification task to test how Tagalog-speaking adults and 5- and 7-year-old children process reversible transitive sentences. Results showed that adults performed well in all conditions, while children’s accuracy and listening times for the first noun phrase indicated more difficulty in interpreting patient-initial sentences in the agent voice compared to the patient voice. The patient voice advantage is partly explained by both the frequency account and incremental processing account.

Abstract

The way the human brain represents speech in memory is still unknown. An obvious characteristic of speech is its evolvement over time.
During speech processing, neural oscillations are modulated by the temporal properties of the acoustic speech signal, but also acquired
knowledge on the temporal structure of language influences speech perception-related brain activity. This suggests that speech could be
represented in the temporal domain, a form of representation that the brain also uses to encode autobiographic memories. Empirical
evidence for such a memory code is lacking. We investigated the nature of speech memory representations using direct cortical recordings
in the left perisylvian cortex during delayed sentence reproduction in female and male patients undergoing awake tumor surgery.
Our results reveal that the brain endogenously represents speech in the temporal domain. Temporal pattern similarity analyses revealed
that the phase of frontotemporal low-frequency oscillations, primarily in the beta range, represents sentence identity in working memory.
The positive relationship between beta power during working memory and task performance suggests that working memory
representations benefit from increased phase separation.

Abstract

Developmental dyslexia (DD) is one of the most prevalent learning disorders, with high impact on school and psychosocial development and high comorbidity with conditions like attention-deficit hyperactivity disorder (ADHD), depression, and anxiety. DD is characterized by deficits in different cognitive skills, including word reading, spelling, rapid naming, and phonology. To investigate the genetic basis of DD, we conducted a genome-wide association study (GWAS) of these skills within one of the largest studies available, including nine cohorts of reading-impaired and typically developing children of European ancestry (N = 2562–3468). We observed a genome-wide significant effect (p < 1 × 10−8) on rapid automatized naming of letters (RANlet) for variants on 18q12.2, within MIR924HG (micro-RNA 924 host gene; rs17663182 p = 4.73 × 10−9), and a suggestive association on 8q12.3 within NKAIN3 (encoding a cation transporter; rs16928927, p = 2.25 × 10−8). rs17663182 (18q12.2) also showed genome-wide significant multivariate associations with RAN measures (p = 1.15 × 10−8) and with all the cognitive traits tested (p = 3.07 × 10−8), suggesting (relational) pleiotropic effects of this variant. A polygenic risk score (PRS) analysis revealed significant genetic overlaps of some of the DD-related traits with educational attainment (EDUyears) and ADHD. Reading and spelling abilities were positively associated with EDUyears (p ~ [10−5–10−7]) and negatively associated with ADHD PRS (p ~ [10−8−10−17]). This corroborates a long-standing hypothesis on the partly shared genetic etiology of DD and ADHD, at the genome-wide level. Our findings suggest new candidate DD susceptibility genes and provide new insights into the genetics of dyslexia and its comorbities.

Abstract

The neural infrastructure for sentence production and comprehension has been found to be mostly shared. The same regions are engaged during speaking and listening, with some differences in how strongly they activate depending on modality. In this study, we investigated how modality affects the connectivity between regions previously found to be involved in syntactic processing across modalities. We determined how constituent size and modality affected the connectivity of the pars triangularis of the left inferior frontal gyrus (LIFG) and of the left posterior temporal lobe (LPTL) with the pars opercularis of the LIFG, the anterior temporal lobe (LATL) and the rest of the brain. We found that constituent size reliably increased the connectivity across these frontal and temporal ROIs. Connectivity between the two LIFG regions and the LPTL was enhanced as a function of constituent size in both modalities, and it was upregulated in production possibly because of linearization and motor planning in the frontal cortex. The connectivity of both ROIs with the LATL was lower and only enhanced for larger constituent sizes, suggesting a contributing role of the LATL in sentence processing in both modalities. These results thus show that the connectivity among fronto-temporal regions is upregulated for syntactic structure building in both sentence production and comprehension, providing further evidence for accounts of shared neural resources for sentence-level processing across modalities.

Abstract

The neural correlates of sentence production have been mostly studied with constraining task paradigms that introduce artificial task effects. In this study, we aimed to gain a better understanding of syntactic processing in spontaneous production vs. naturalistic comprehension. We extracted word-by-word metrics of phrase-structure building with top-down and bottom-up parsers that make different hypotheses about the timing of structure building. In comprehension, structure building proceeded in an integratory fashion and led to an increase in activity in posterior temporal and inferior frontal areas. In production, structure building was anticipatory and predicted an increase in activity in the inferior frontal gyrus. Newly developed production-specific parsers highlighted the anticipatory and incremental nature of structure building in production, which was confirmed by a converging analysis of the pausing patterns in speech. Overall, the results showed that the unfolding of syntactic processing diverges between speaking and listening.

Abstract

Irrelevant speech effect (ISE) is defined as a decrement in visually presented digit-list short-term memory performance due to exposure to irrelevant auditory material. Perhaps the most successful theoretical explanation of the effect is the changing state hypothesis. This hypothesis explains the effect in terms of confusion between amodal serial order cues, and represents a view based on the interference caused by the processing of similar order information of the visual and auditory materials. An alternative view suggests that the interference occurs as a consequence of the similarity between the visual and auditory contents of the stimuli. An important argument for the former view is the observation that ISE is almost exclusively observed in tasks that require memory for serial order. However, most short-term memory tasks require that both item and order information be retained in memory. An ideal task to investigate the sensitivity of maintenance of serial order to irrelevant speech would be one that calls upon order information but not item information. One task that is particularly suited to address this issue is serial recognition. In a typical serial recognition task, a list of items is presented and then probed by the same list in which the order of two adjacent items has been transposed. Due to the re-presentation of the encoding string, serial recognition requires primarily the serial order to be maintained while the content of the presented items is deemphasized. In demonstrating a highly significant ISE of changing versus steady-state auditory items in a serial recognition task, the present finding lends support for and extends previous empirical findings suggesting that irrelevant speech has the potential to interfere with the coding of the order of the items to be memorized.

Abstract

Using parametric and nonparametric techniques, our study investigated the presence of single locus and pairwise effects between 20 markers of the Genetic Analysis Workshop 15 (GAW15) North American Rheumatoid Arthritis Consortium (NARAC) candidate gene data set (Problem 2), analyzing 463 independent patients and 855 controls. Specifically, our work examined the correspondence between logistic regression (LR) analysis of single-locus and pairwise interaction effects, and random forest (RF) single and joint importance measures. For this comparison, we selected small but stable RFs (500 trees), which showed strong correlations (r~0.98) between their importance measures and those by RFs grown on 5000 trees. Both RF importance measures captured most of the LR single-locus and pairwise interaction effects, while joint importance measures also corresponded to full LR models containing main and interaction effects. We furthermore showed that RF measures were particularly sensitive to data imputation. The most consistent pairwise effect on rheumatoid arthritis was found between two markers within MAP3K7IP2/SUMO4 on 6q25.1, although LR and RFs assigned different significance levels. Within a hypothetical two-stage design, pairwise LR analysis of all markers with significant RF single importance would have reduced the number of possible combinations in our small data set by 61%, whereas joint importance measures would have been less efficient for marker pair reduction. This suggests that RF single importance measures, which are able to detect a wide range of interaction effects and are computationally very efficient, might be exploited as pre-screening tool for larger association studies. Follow-up analysis, such as by LR, is required since RFs do not indicate highrisk genotype combinations.

Abstract

Patterns formed by reaction-diffusion mechanisms are crucial for the development or sustenance of most organisms in nature. Patterns include dynamic waves, but are more often found as static distributions, such as animal skin patterns. Yet, a simplistic biological model system to reproduce and quantitatively investigate static reaction-diffusion patterns has been missing so far. Here, we demonstrate that the Escherichia coli MM system, known for its oscillatory behavior between the cell poles, is under certain conditions capable of transitioning to quasi-stationary protein distributions on membranes closely resembling Turing patterns. We systematically titrated both proteins, MinD and MinE, and found that removing all purification tags and linkers from the N-terminus of MinE was critical for static patterns to occur. At small bulk heights, dynamic patterns dominate, such as in rod-shaped microcompartments. We see implications of this work for studying pattern formation in general, but also for creating artificial gradients as downstream cues in synthetic biology applications.

Abstract

Children need to learn the demands of their native language in the early vocabulary development phase. In this dynamic process, parental multimodal input may shape neurodevelopmental trajectories while also being tailored by child-related factors. Moving beyond typically characterized group profiles, in this article, we synthesize growing evidence on the effects of parental multimodal input (amount, quality, or absence), domain-specific input (space and math), and language-specific input (causal verbs and sound symbols) on preterm, full-term, and deaf children's early vocabulary development, focusing primarily on research with children learning Turkish and Turkish Sign Language. We advocate for a theoretical perspective, integrating neonatal characteristics and parental input, and acknowledging the unique constraints of languages.

Abstract

To test whether the language we speak influences our behavior even when we are not speaking, we asked speakers of four languages differing in their predominant word orders (English, Turkish, Spanish, and Chinese) to perform two nonverbal tasks: a communicative task (describing an event by using gesture without speech) and a noncommunicative task (reconstructing an event with pictures). We found that the word orders speakers used in their everyday speech did not influence their nonverbal behavior. Surprisingly, speakers of all four languages used the same order and on both nonverbal tasks. This order, actor–patient–act, is analogous to the subject–object–verb pattern found in many languages of the world and, importantly, in newly developing gestural languages. The findings provide evidence for a natural order that we impose on events when describing and reconstructing them nonverbally and exploit when constructing language anew.

Abstract

Interactive models of language production predict that it should be possible to observe long-distance interactions; effects that arise at one level of processing influence multiple subsequent stages of representation and processing. We examine the hypothesis that disruptions arising in nonform-based levels of planning—specifically, lexical selection—should modulate articulatory processing. A novel automatic phonetic analysis method was used to examine productions in a paradigm yielding both general disruptions to formulation processes and, more specifically, overt errors during lexical selection. This analysis method allowed us to examine articulatory disruptions at multiple levels of analysis, from whole words to individual segments. Baseline performance by young adults was contrasted with young speakers’ performance under time pressure (which previous work has argued increases interaction between planning and articulation) and performance by older adults (who may have difficulties inhibiting nontarget representations, leading to heightened interactive effects). The results revealed the presence of interactive effects. Our new analysis techniques revealed these effects were strongest in initial portions of responses, suggesting that speech is initiated as soon as the first segment has been planned. Interactive effects did not increase under response pressure, suggesting interaction between planning and articulation is relatively fixed. Unexpectedly, lexical selection disruptions appeared to yield some degree of facilitation in articulatory processing (possibly reflecting semantic facilitation of target retrieval) and older adults showed weaker, not stronger interactive effects (possibly reflecting weakened connections between lexical and form-level representations).

Abstract

* Ole Goltermann and Gökberk Alagöz contributed equally.
Primate brain evolution has involved prominent expansions of the cerebral cortex, with largest effects observed in the human lineage. Such expansions were accompanied by fine-grained anatomical alterations, including increased cortical folding. However, the molecular bases of evolutionary alterations in human sulcal organization are not yet well understood. Here, we integrated data from recently completed large-scale neuroimaging genetic analyses with annotations of the human genome relevant to various periods and events in our evolutionary history. These analyses identified single-nucleotide polymorphism (SNP) heritability enrichments in fetal brain human-gained enhancer (HGE) elements for a number of sulcal structures, including the central sulcus, which is implicated in human hand dexterity. We zeroed in on a genomic region that harbors DNA variants associated with left central sulcus shape, an HGE element, and genetic loci involved in neurogenesis including ZIC4, to illustrate the value of this approach for probing the complex factors contributing to human sulcal evolution.

Abstract

Chicks can convey information about their needs with calls. But it is still unknown if there are any universal need indicators in chick vocalizations. Previous studies have shown that in some species vocal activity and/or temporal-frequency variables of calls are related to the chick state, whereas other studies did not confirm it. Here, we tested experimentally whether vocal activity and temporal-frequency variables of calls change with cooling. We studied 10 human-raised
Siberian crane (Grus leucogeranus) chicks at 3–15 days of age. We found that the cooled chicks produced calls higher in fundamental
frequency and power variables, longer in duration and at a higher calling rate than in the control chicks. However, we did not find
significant changes in level of entropy and occurrence of non-linear phenomena in chick calls recorded during the experimental cooling. We suggest that the level of vocal activity is a universal indicator of need for warmth in precocial and semi-precocial birds (e.g. cranes), but not in altricial ones. We also assume that coding of needs via temporal-frequency variables of calls is typical in species whose adults could not confuse their chicks with other chicks. Siberian cranes stay on separate territories during their breeding season, so parents do not need to check individuality of their offspring in the home area. In this case, all call characteristics are available for other purposes and serve to communicate chicks’ vital needs.

Abstract

Formants, or resonance frequencies of the upper vocal tract, are an essential part of acoustic communication. Articulatory gestures—such as jaw, tongue, lip, and soft palate movements—shape formant structure in human vocalizations, but little is known about how nonhuman mammals use those gestures to modify formant frequencies. Here, we report a case study with an adult male harbor seal trained to produce an arbitrary vocalization composed of multiple repetitions of the sound wa. We analyzed jaw movements frame-by-frame and matched them to the tracked formant modulation in the corresponding vocalizations. We found that the jaw opening angle was strongly correlated with the first (F1) and, to a lesser degree, with the second formant (F2). F2 variation was better explained by the jaw angle opening when the seal was lying on his back rather than on the belly, which might derive from soft tissue displacement due to gravity. These results show that harbor seals share some common articulatory traits with humans, where the F1 depends more on the jaw position than F2. We propose further in vivo investigations of seals to further test the role of the tongue on formant modulation in mammalian sound production.

Abstract

Background

Schizophrenia is a highly heritable disorder characterized by increased cortical thinning throughout the lifespan. Studies have reported a shared genetic basis between schizophrenia and cortical thickness. However, no genes whose expression is related to abnormal cortical thinning in schizophrenia have been identified.

Methods

We conducted linear mixed models to estimate the rates of accelerated cortical thinning across 68 regions from the Desikan-Killiany atlas in individuals with schizophrenia compared to healthy controls from a large longitudinal sample (NCases = 169 and NControls = 298, aged 16-70 years). We studied the correlation between gene expression data from the Allen Human Brain Atlas and accelerated thinning estimates across cortical regions. We finally explored the functional and genetic underpinnings of the genes most contributing to accelerated thinning.

Results

We described a global pattern of accelerated cortical thinning in individuals with schizophrenia compared to healthy controls. Genes underexpressed in cortical regions exhibiting this accelerated thinning were downregulated in several psychiatric disorders and were enriched for both common and rare disrupting variation for schizophrenia and neurodevelopmental disorders. In contrast, none of these enrichments were observed for baseline cross-sectional cortical thickness differences.

Conclusions

Our findings suggest that accelerated cortical thinning, rather than cortical thickness alone, serves as an informative phenotype for neurodevelopmental disruptions in schizophrenia. We highlight the genetic and transcriptomic correlates of this accelerated cortical thinning, emphasizing the need for future longitudinal studies to elucidate the role of genetic variation and the temporal-spatial dynamics of gene expression in brain development and aging in schizophrenia.

Abstract

When language abilities in aphasia are assessed in clinical and research settings, the standard practice is to examine each language of a multilingual person separately. But many multilingual individuals, with and without aphasia, mix their languages regularly when they communicate with other speakers who share their languages. We applied a novel approach to scoring language production of a multilingual person with aphasia. Our aim was to discover whether the assessment outcome would differ meaningfully when we count accurate responses in only the target language of the assessment session versus when we apply a translanguaging framework, that is, count all accurate responses, regardless of the language in which they were produced. The participant is a Farsi-German-English speaking woman with chronic moderate aphasia. We examined the participant’s performance on two picture-naming tasks, an answering wh-question task, and an elicited narrative task. The results demonstrated that scores in English, the participant’s third-learned and least-impaired language did not differ between the two scoring methods. Performance in German, the participant’s moderately impaired second language benefited from translanguaging-based scoring across the board. In Farsi, her weakest language post-CVA, the participant’s scores were higher under the translanguaging-based scoring approach in some but not all of the tasks. Our findings suggest that whether a translanguaging-based scoring makes a difference in the results obtained depends on relative language abilities and on pragmatic constraints, with additional influence of the linguistic distances between the languages in question.

Abstract

The acquisition of novel phonetic categories is hypothesized to be affected by the distributional properties of the input, the relation of the new categories to the native phonology, and the availability of supervision (feedback). These factors were examined in four experiments in which listeners were presented with novel categories based on vowels of Dutch. Distribution was varied such that the categorization depended on the single dimension duration, the single dimension frequency, or both dimensions at once. Listeners were clearly sensitive to the distributional information, but unidimensional contrasts proved easier to learn than multidimensional. The native phonology was varied by comparing Spanish versus American English listeners. Spanish listeners found categorization by frequency easier than categorization by duration, but this was not true of American listeners, whose native vowel system makes more use of duration-based distinctions. Finally, feedback was either available or not; this comparison showed supervised learning to be significantly superior to unsupervised learning.

Abstract

Languages, like molecules, document evolutionary history. Darwin(1) observed that evolutionary change in languages greatly resembled the processes of biological evolution: inheritance from a common ancestor and convergent evolution operate in both. Despite many suggestions(2-4), few attempts have been made to apply the phylogenetic methods used in biology to linguistic data. Here we report a parsimony analysis of a large language data set. We use this analysis to test competing hypotheses - the "express-train''(5) and the "entangled-bank''(6,7) models - for the colonization of the Pacific by Austronesian-speaking peoples. The parsimony analysis of a matrix of 77 Austronesian languages with 5,185 lexical items produced a single most-parsimonious tree. The express-train model was converted into an ordered geographical character and mapped onto the language tree. We found that the topology of the language tree was highly compatible with the express-train model.

Abstract

The search for common characteristics between the musical abilities of humans and other animal species is still taking its first steps. One of the most promising aspects from a comparative point of view is the analysis of rhythmic components, which are crucial features of human communicative performance but also well-identifiable patterns in the vocal displays of other species. Therefore, the study of rhythm is becoming essential to understand the mechanisms of singing behavior and the evolution of human communication. Recent findings provided evidence that particular rhythmic structures occur in human music and some singing animal species, such as birds and rock hyraxes, but only 2 species of nonhuman primates have been investigated so far (Indri indri and Hylobates lar). Therefore, our study aims to consistently broaden the list of species studied regarding the presence of rhythmic categories. We investigated the temporal organization in the singing of 3 species of crested gibbons (Nomascus gabriellae, Nomascus leucogenys, and Nomascus siki) and found that the most prominent rhythmic category was isochrony. Moreover, we found slight variation in songs’ tempo among species, with N. gabriellae and N. siki singing with a temporal pattern involving a gradually increasing tempo (a musical accelerando), and N. leucogenys with a more regular pattern. Here, we show how the prominence of a peak at the isochrony establishes itself as a shared characteristic in the small apes considered so far.

Abstract

Animal songs differ from calls in function and structure, and have comparative and translational value, showing similarities to human music. Rhythm in music is often distributed in quantized classes of intervals known as rhythmic categories. These classes have been found in the songs of a few nonhuman species but never in their calls. Are rhythmic categories song-specific, as in human music, or can they transcend the song–call boundary? We analyze the vocal displays of one of the few mammals producing both songs and call sequences: Indri indri. We test whether rhythmic categories (a) are conserved across songs produced in different contexts, (b) exist in call sequences, and (c) differ between songs and call sequences. We show that rhythmic categories occur across vocal displays. Vocalization type and function modulate deployment of categories. We find isochrony (1:1 ratio, like the rhythm of a ticking clock) in all song types, but only advertisement songs show three rhythmic categories (1:1, 1:2, 2:1 ratios). Like songs, some call types are also isochronous. Isochrony is the backbone of most indri vocalizations, unlike human speech, where it is rare. In indri, isochrony underlies both songs and hierarchy-less call sequences and might be ancestral to both.

Abstract

This study examined electrophysiological correlates of sentence comprehension of native-accented and foreign-accented
speech in a second language (L2), for sentences produced in a foreign accent different from that associated with the listeners’
L1. Bilingual speaker-listeners process different accents in their L2 conversations, but the effects on real-time L2 sentence
comprehension are unknown. Dutch–English bilinguals listened to native American-English accented sentences and foreign
(and for them unfamiliarly-accented) Chinese-English accented sentences while EEG was recorded. Behavioral sentence
comprehension was highly accurate for both native-accented and foreign-accented sentences. ERPs showed different patterns
for L2 grammar and semantic processing of native- and foreign-accented speech. For grammar, only native-accented speech
elicited an Nref. For semantics, both native- and foreign-accented speech elicited an N400 effect, but with a delayed onset
across both accent conditions. These findings suggest that the way listeners comprehend native- and foreign-accented
sentences in their L2 depends on their familiarity with the accent.

Abstract

To study the time course of sentence formulation, we monitored the eye movements of speakers as they described simple events. The similarity between speakers' initial eye movements and those of observers performing a nonverbal event-comprehension task suggested that response-relevant information was rapidly extracted from scenes, allowing speakers to select grammatical subjects based on comprehended events rather than salience. When speaking extemporaneously, speakers began fixating pictured elements less than a second before naming them within their descriptions, a finding consistent with incremental lexical encoding. Eye movements anticipated the order of mention despite changes in picture orientation, in who-did-what-to-whom, and in sentence structure. The results support Wundt's theory of sentence production.

Abstract

The most well-described example of an inherited speech and language disorder is that observed in the multigenerational KE family, caused by a heterozygous missense mutation in the FOXP2 gene. Affected individuals are characterized by deficits in the learning and production of complex orofacial motor sequences underlying fluent speech and display impaired linguistic processing for both spoken and written language. The FOXP2 transcription factor is highly similar in many vertebrate species, with conserved expression in neural circuits related to sensorimotor integration and motor learning. In this study, we generated mice carrying an identical point mutation to that of the KE family, yielding the equivalent arginine-to-histidine substitution in the Foxp2 DNA-binding domain. Homozygous R552H mice show severe reductions in cerebellar growth and postnatal weight gain but are able to produce complex innate ultrasonic vocalizations. Heterozygous R552H mice are overtly normal in brain structure and development. Crucially, although their baseline motor abilities appear to be identical to wild-type littermates, R552H heterozygotes display significant deficits in species-typical motor-skill learning, accompanied by abnormal synaptic plasticity in striatal and cerebellar neural circuits.

Abstract

Autism spectrum disorder (ASD) is a highly heritable and heterogeneous group of neurodevelopmental phenotypes diagnosed in more than 1% of children. Common genetic variants contribute substantially to ASD susceptibility, but to date no individual variants have been robustly associated with ASD. With a marked sample-size increase from a unique Danish population resource, we report a genome-wide association meta-analysis of 18,381 individuals with ASD and 27,969 controls that identified five genome-wide-significant loci. Leveraging GWAS results from three phenotypes with significantly overlapping genetic architectures (schizophrenia, major depression, and educational attainment), we identified seven additional loci shared with other traits at equally strict significance levels. Dissecting the polygenic architecture, we found both quantitative and qualitative polygenic heterogeneity across ASD subtypes. These results highlight biological insights, particularly relating to neuronal function and corticogenesis, and establish that GWAS performed at scale will be much more productive in the near term in ASD.

Abstract

The aim of this article is to analyze the funerary customs and ritual for the souls among contemporary Yucatec Maya in order to better understand their relations with pre-Hispanic burial patterns. It is suggested that the souls of the dead are considered as ancestors that can be distinguished between family and collective ancestors considering several criteria: the place of burial, the place of ritual performance and the ritual treatment. In this proposition, funerary practices as well as ritual categories of ancestors (family or collective), are considered as reminiscences of ancient practices whose traces can be found throughout historical sources. Through an analyze of the current funerary practices and their variations, this article aims to demonstrate that over the time and despite socio-economical changes, ancient funerary practices (specifically from the post-classic period) had kept some homogeneity, preserving some essential characteristics that can be observed in the actuality.

Abstract

Partisan gerrymandering poses a threat to democracy. Moreover, the complexity of the districting task may exceed human capacities. One potential solution is using computational models to automate the districting process by optimizing objective and open criteria, such as how spatially compact districts are. We formulated one such model that minimised pairwise distance between voters within a district. Using US Census Bureau data, we confirmed our prediction that the difference in compactness between the computed and actual districts would be greatest for states that are large and, therefore, difficult for humans to properly district given their limited capacities. The computed solutions highlighted differences in how humans and machines solve this task with machine solutions more fully optimised and displaying emergent properties not evident in human solutions. These results suggest a division of labour in which humans debate and formulate districting criteria whereas machines optimise the criteria to draw the district boundaries. We discuss how criteria can be expanded beyond notions of compactness to include other factors, such as respecting municipal boundaries, historic communities, and relevant legislation.

Abstract

The purpose of the current paper is to outline how gestures can contribute to the study of some key issues in language development. Specifically, we (1) briefly summarise what is already known about gesture in the domains of first and second language development, and development or changes over the life span more generally; (2) highlight theoretical and empirical issues in these domains where gestures can contribute in important ways to further our understanding; and (3) summarise some common themes in all strands of research on language development that could be the target of concentrated research efforts.

Abstract

The title of this special issue, Gesture and SLA: Toward an Integrated Approach, stems in large part from the idea known as integrationism, principally set forth by Harris (2003, 2005), which posits that it is time to “demythologize” linguistics, moving away from the “orthodox exponents” that have idealized the notion of language. The integrationist approach intends a view that focuses on communication—that is, language in use, language as a “fact of life” (Harris, 2003, p. 50). Although not all gesture studies embrace an integrationist view—indeed, the field applies numerous theories across various disciplines—it is nonetheless true that to study gesture is to study what has traditionally been called paralinguistic modes of interaction, with the paralinguistic label given on the assumption that gesture is not part of the core meaning of what is rendered linguistically. However, arguably, most researchers within gesture studies would maintain just the opposite: The studies presented in this special issue reflect a view whereby gesture is regarded as a central aspect of language in use, integral to how we communicate (make meaning) both with each other and with ourselves.

Abstract

This study explores how French adults and children aged four and six years talk and gesture about voluntary motion, examining (1) how they encode path and manner in speech, (2) how they encode this information in accompanying gestures; and (3) whether gestures are co-expressive with speech or express other information. When path and manner are equally relevant, children’s and adults’ speech and gestures both focus on path, rather than on manner. Moreover, gestures are predominantly co-expressive with speech at all ages. However, when they are non-redundant, adults tend to gesture about path while talking about manner, whereas children gesture about both path and manner while talking about path. The discussion highlights implications for our understanding of speakers’ representations and their development.

Abstract

One of the features that distinguishes modern humans from our extinct relatives
and ancestors is a globular shape of the braincase [1-4]. As the endocranium
closely mirrors the outer shape of the brain, these differences might reflect
altered neural architecture [4,5]. However, in the absence of fossil brain tissue the
underlying neuroanatomical changes as well as their genetic bases remain
elusive. To better understand the biological foundations of modern human
endocranial shape, we turn to our closest extinct relatives, the Neandertals.
Interbreeding between modern humans and Neandertals has resulted in
introgressed fragments of Neandertal DNA in the genomes of present-day non-
Africans [6,7]. Based on shape analyses of fossil skull endocasts, we derive a
measure of endocranial globularity from structural magnetic resonance imaging
(MRI) scans of thousands of modern humans, and study the effects of
introgressed fragments of Neandertal DNA on this phenotype. We find that
Neandertal alleles on chromosomes 1 and 18 are associated with reduced
endocranial globularity. These alleles influence expression of two nearby genes,
UBR4 and PHLPP1, which are involved in neurogenesis and myelination,
respectively. Our findings show how integration of fossil skull data with archaic
genomics and neuroimaging can suggest developmental mechanisms that may
contribute to the unique modern human endocranial shape.

Abstract

Claims that neuroscientific data do not contribute to our understanding of psychological functions have been made recently. Here I argue that these criticisms are solely based on an analysis of functional magnetic resonance imaging (fMRI) studies. However, fMRI is only one of the methods in the toolkit of cognitive neuroscience. I provide examples from research on event-related brain potentials (ERPs) that have contributed to our understanding of the cognitive architecture of human language functions. In addition, I provide evidence of (possible) contributions from fMRI measurements to our understanding of the functional architecture of language processing. Finally, I argue that a neurobiology of human language that integrates information about the necessary genetic and neural infrastructures will allow us to answer certain questions that are not answerable if all we have is evidence from behavior.

Abstract

This paper focuses on what electrical and magnetic recordings of human brain activity reveal about spoken language understanding. Based on the high temporal resolution of these recordings, a fine-grained temporal profile of different aspects of spoken language comprehension can be obtained. Crucial aspects of speech comprehension are lexical access, selection and semantic integration. Results show that for words spoken in context, there is no ‘magic moment’ when lexical selection ends and semantic integration begins. Irrespective of whether words have early or late recognition points, semantic integration processing is initiated before words can be identified on the basis of the acoustic information alone. Moreover, for one particular event-related brain potential (ERP) component (the N400), equivalent impact of sentence- and discourse-semantic contexts is observed. This indicates that in comprehension, a spoken word is immediately evaluated relative to the widest interpretive domain available. In addition, this happens very quickly. Findings are discussed that show that often an unfolding word can be mapped onto discourse-level representations well before the end of the word. Overall, the time course of the ERP effects is compatible with the view that the different information types (lexical, syntactic, phonological, pragmatic) are processed in parallel and influence the interpretation process incrementally, that is as soon as the relevant pieces of information are available. This is referred to as the immediacy principle.

Abstract

In this study, event-related brain potential ffects of speech processing are obtained and compared to similar effects in sentence reading. In two experiments sentences were presented that contained three different types of grammatical violations. In one experiment sentences were presented word by word at a rate of four words per second. The grammatical violations elicited a Syntactic Positive Shift (P600/SPS), 500 ms after the onset of the word that rendered the sentence ungrammatical. The P600/SPS consisted of two phases, an early phase with a relatively equal anterior-posterior distribution and a later phase with a strong posterior distribution. We interpret the first phase as an indication of structural integration complexity, and the second phase as an indication of failing parsing operations and/or an attempt at reanalysis. In the second experiment the same syntactic violations were presented in sentences spoken at a normal rate and with normal intonation. These violations elicited a P600/SPS with the same onset as was observed for the reading of these sentences. In addition two of the three violations showed a preceding frontal negativity, most clearly over the left hemisphere.

Abstract

In this study, event-related brain potential effects of speech processing are obtained and compared to similar effects insentence reading. In two experiments spoken sentences were presented with semantic violations in sentence-signal or mid-sentence positions. For these violations N400 effects were obtained that were very similar to N400 effects obtained in reading. However, the N400 effects in speech were preceded by an earlier negativity (N250). This negativity is not commonly observed with written input. The early effect is explained as a manifestation of a mismatch between the word forms expected on the basis of the context, and the actual cohort of activated word candidates that is generated on the basis of the speech signal.

Abstract

In an event-related potential experiment with Chinese discourses as material, we investigated how and when accentuation influences spoken discourse comprehension in relation to the different information states of the critical words. These words could either provide new or old information. It was shown that variation of accentuation influenced the amplitude of the N400, with a larger amplitude for accented than deaccented words. In addition, there was an interaction between accentuation and information state. The N400 amplitude difference between accented and deaccented new information was smaller than that between accented and deaccented old information. The results demonstrate that, during spoken discourse comprehension, listeners rapidly extract the semantic consequences of accentuation in relation to the previous discourse context. Moreover, our results show that the N400 amplitude can be larger for correct (new,accented words) than incorrect (new, deaccented words) information. This, we argue, proves that the N400 does not react to semantic anomaly per se, but rather to semantic integration load, which is higher for new information.

Abstract

A central and influential idea among researchers of language is that our language faculty is organized according to Fregean compositionality, which states that the meaning of an utterance is a function of the meaning of its parts and of the syntactic rules by which these parts are combined. Since the domain of syntactic rules is the sentence, the implication of this idea is that language interpretation takes place in a two-step fashion. First, the meaning of a sentence is computed. In a second step, the sentence meaning is integrated with information from prior discourse, world knowledge, information about the speaker and semantic information from extra-linguistic domains such as co-speech gestures or the visual world. Here, we present results from recordings of event-related brain potentials that are inconsistent with this classical two-step model of language interpretation. Our data support a one-step model in which knowledge about the context and the world, concomitant information from other modalities, and the speaker are brought to bear immediately, by the same fast-acting brain system that combines the meanings of individual words into a message-level representation. Underlying the one-step model is the immediacy assumption, according to which all available information will immediately be used to co-determine the interpretation of the speaker's message. Functional magnetic resonance imaging data that we collected indicate that Broca's area plays an important role in semantic unification. Language comprehension involves the rapid incorporation of information in a 'single unification space', coming from a broader range of cognitive domains than presupposed in the standard two-step model of interpretation.

Abstract

In this contribution, the following four questions are discussed: (i) where is meaning?; (ii) what is meaning?; (iii) what is the meaning of mechanism?; (iv) what are the mechanisms of meaning? I will argue that meanings are in the head. Meanings have multiple facets, but minimally one needs to make a distinction between single word meanings (lexical meaning) and the meanings of multi-word utterances. The latter ones cannot be retrieved from memory, but need to be constructed on the fly. A mechanistic account of the meaning-making mind requires an analysis at both a functional and a neural level, the reason being that these levels are causally interdependent. I will show that an analysis exclusively focusing on patterns of brain activation lacks explanatory power. Finally, I shall present an initial sketch of how the dynamic interaction between temporo-parietal areas and inferior frontal cortex might instantiate the interpretation of linguistic utterances in the context of a multimodal setting and ongoing discourse information.

Abstract

In this Review, I propose a multiple-network view for the neurobiological basis of distinctly human language skills. A much more complex picture of interacting brain areas emerges than in the classical neurobiological model of language. This is because using language is more than single-word processing, and much goes on beyond the information given in the acoustic or orthographic tokens that enter primary sensory cortices. This requires the involvement of multiple networks with functionally nonoverlapping contributions

Abstract

Language is inherently multimodal. In spoken languages, combined spoken and visual signals (e.g., co-speech gestures) are an integral part of linguistic structure and language representation. This requires an extension of the parallel architecture, which needs to include the visual signals concomitant to speech. We present the evidence for the multimodality of language. In addition, we propose that distributional semantics might provide a format for integrating speech and co-speech gestures in a common semantic representation.

Abstract

In an ERP experiment we investigated how the recruitment and integration of world knowledge information relate to the integration of information within a current discourse context. Participants were presented with short discourse contexts which were followed by a sentence that contained a critical word that was correct or incorrect based on general world knowledge and the supporting discourse context, or was more or less acceptable based on the combination of general world knowledge and the specific local discourse context. Relative to the critical word in the correct world knowledge sentences following a neutral discourse, all other critical words elicited an N400 effect that began at about 300 ms after word onset. However, the magnitude of the N400 effect varied in a way that suggests an interaction between world knowledge and discourse context. The results indicate that both world knowledge and discourse context have an effect on sentence interpretation, but neither overrides the other.

Abstract

Written language comprehension at the word and the sentence level was analysed by the combination of spatial and temporal analysis of functional magnetic resonance imaging (fMRI). Spatial analysis was performed via general linear modelling (GLM). Concerning the temporal analysis, local differences in neurovascular coupling may confound a direct comparison of blood oxygenation level-dependent (BOLD) response estimates between regions. To avoid this problem, we parametrically varied linguistic task demands and compared only task-induced within-region BOLD response differences across areas. We reasoned that, in a hierarchical processing system, increasing task demands at lower processing levels induce delayed onset of higher-level processes in corresponding areas. The flow of activation is thus reflected in the size of task-induced delay increases. We estimated BOLD response delay and duration for each voxel and each participant by fitting a model function to the event-related average BOLD response. The GLM showed increasing activations with increasing linguistic demands dominantly in the left inferior frontal gyrus (IFG) and the left superior temporal gyrus (STG). The combination of spatial and temporal analysis allowed a functional differentiation of IFG subregions involved in written language comprehension. Ventral IFG region (BA 47) and STG subserve earlier processing stages than two dorsal IFG regions (BA 44 and 45). This is in accordance with the assumed early lexical semantic and late syntactic processing of these regions and illustrates the complementary information provided by spatial and temporal fMRI data analysis of the same data set.

Abstract

Rheumatoid arthritis is the most common systematic autoimmune disease and its etiology is believed to have both strong genetic and environmental components. We demonstrate the utility of including genetic and clinical phenotypes as covariates within a linkage analysis framework to search for rheumatoid arthritis susceptibility loci. The raw genotypes of 1302 affected relative pairs were combined from four large family-based samples (North American Rheumatoid Arthritis Consortium, United Kingdom, European Consortium on Rheumatoid Arthritis Families, and Canada). The familiality of the clinical phenotypes was assessed. The affected relative pairs were subjected to autosomal multipoint affected relative-pair linkage analysis. Covariates were included in the linkage analysis to take account of heterogeneity within the sample. Evidence of familiality was observed with age at onset (p <} 0.001) and rheumatoid factor (RF) IgM (p {< 0.001), but not definite erosions (p = 0.21). Genome-wide significant evidence for linkage was observed on chromosome 6. Genome-wide suggestive evidence for linkage was observed on chromosomes 13 and 20 when conditioning on age at onset, chromosome 15 conditional on gender, and chromosome 19 conditional on RF IgM after allowing for multiple testing of covariates.

Abstract

Speech production studies have shown that phonological unit initially used to fill the metrical frame during phonological encoding is language specific, that is, a phoneme for English and Dutch, an atonal syllable for Mandarin Chinese, and a mora for Japanese. However, only a few studies chronometrically investigated speech production in Korean, and they obtained mixed results. Korean is particularly interesting as there might be both phonemic and syllabic influences during phonological encoding. The purpose of this study is to further examine the initial phonological preparation unit in Korean, employing a masked priming task (Experiment 1) and a phonological Stroop task (Experiment 2). The results showed that significant onset (and onset-plus, that is, consonant-vowel [CV]) effects were found in both experiments, but there was no compelling evidence for a prominent role for the syllable. When the prime words were presented in three different forms related to the targets, namely, without any change, with re-syllabified codas, and with nasalised codas, there were no significant differences in facilitation among the three forms. Alternatively, it is also possible that participants may not have had sufficient time to process the primes up to the point that re-syllabification or nasalisation could have been carried out. In addition, the results of a Stroop task demonstrated that the onset phoneme effect was not driven by any orthographic influence. These findings suggest that the onset segment and not the syllable is the initial (or proximate) phonological unit used in the segment-to-frame encoding process during speech planning in Korean.

Abstract

Feedback has been shown to be effective in shifting attention across perceptual cues to a phonological contrast in speech perception (Francis, Baldwin & Nusbaum, 2000). However, the learning mechanisms behind this process remain obscure. We compare the predictions of supervised error-driven learning (Rescorla & Wagner, 1972) and reinforcement learning (Sutton & Barto, 1998) using computational simulations. Supervised learning predicts downweighting of an informative cue when the learner receives evidence that it is no longer informative. In contrast, reinforcement learning suggests that a reduction in cue weight requires positive evidence for the informativeness of an alternative cue. Experimental evidence supports the latter prediction, implicating reinforcement learning as the mechanism behind the effect of feedback on cue weighting in speech perception. Native English listeners were exposed to either bimodal or unimodal VOT distributions spanning the unaspirated/aspirated boundary (bear/pear). VOT is the primary cue to initial stop voicing in English. However, lexical feedback in training indicated that VOT was no longer predictive of voicing. Reduction in the weight of VOT was observed only when participants could use an alternative cue, F0, to predict voicing. Frequency distributions had no effect on learning. Overall, the results suggest that attention shifting in learning the phonetic cues to phonological categories is accomplished using simple reinforcement learning principles that also guide the choice of actions in other domains.

Abstract

Previous studies have linked the low expression variant of a variable number of tandem repeat polymorphism in the monoamine oxidase A gene (MAOA‐L) to the risk for impulsivity and aggression, brain developmental abnormalities, altered cortico‐limbic circuit function, and an exaggerated neural serotonergic tone. However, the neurobiological effects of this variant on human brain network architecture are incompletely understood. We studied healthy individuals and used multimodal neuroimaging (sample size range: 219–284 across modalities) and network‐based statistics (NBS) to probe the specificity of MAOA‐L‐related connectomic alterations to cortical‐limbic circuits and the emotion processing domain. We assessed the spatial distribution of affected links across several neuroimaging tasks and data modalities to identify potential alterations in network architecture. Our results revealed a distributed network of node links with a significantly increased connectivity in MAOA‐L carriers compared to the carriers of the high expression (H) variant. The hyperconnectivity phenotype primarily consisted of between‐lobe (“anisocoupled”) network links and showed a pronounced involvement of frontal‐temporal connections. Hyperconnectivity was observed across functional magnetic resonance imaging (fMRI) of implicit emotion processing (pFWE = .037), resting‐state fMRI (pFWE = .022), and diffusion tensor imaging (pFWE = .044) data, while no effects were seen in fMRI data of another cognitive domain, that is, spatial working memory (pFWE = .540). These observations are in line with prior research on the MAOA‐L variant and complement these existing data by novel insights into the specificity and spatial distribution of the neurogenetic effects. Our work highlights the value of multimodal network connectomic approaches for imaging genetics.

Abstract

Research on language evolution is an established subject area yet permeated by terminological controversies about which topics should be considered pertinent to the field and which not. By consequence, scholars focusing on language evolution struggle in providing precise demarcations of the discipline, where even the very central notions of evolution and language are elusive. We aimed at providing a data-driven characterisation of language evolution as a field of research by relying on quantitative analysis of data drawn from 697 reviews on 255 submissions from the Joint Conference on Language Evolution 2022 (Kanazawa, Japan). Our results delineate a field characterized by a core of main research topics such as iconicity, sign language, multimodality. Despite being explored within the framework of language evolution research, only very recently these topics became popular in linguistics. As a result, language evolution has the potential to emerge as a forefront of linguistic research, bringing innovation to the study of language. We also see the emergence of more recent topics like rhythm, music, and vocal learning. Furthermore, the community identifies cognitive science, primatology, archaeology, palaeoanthropology, and genetics as key areas, encouraging empirical rather than theoretical work. With new themes, models, and methodologies emerging, our results depict an intrinsically multidisciplinary and evolving research field, likely adapting as language itself.

Abstract

Human infants imitate not only to acquire skill, but also as a fundamental part of social interaction [1] , [2] and [3] . They recognise when they are being imitated by showing increased visual attention to imitators (implicit recognition) and by engaging in so-called testing behaviours (explicit recognition). Implicit recognition affords the ability to recognize structural and temporal contingencies between actions across agents, whereas explicit recognition additionally affords the ability to understand the directional impact of one's own actions on others' actions [1] , [2] and [3] . Imitation recognition is thought to foster understanding of social causality, intentionality in others and the formation of a concept of self as different from other [3] , [4] and [5] . Pigtailed macaques (Macaca nemestrina) implicitly recognize being imitated [6], but unlike chimpanzees [7], they show no sign of explicit imitation recognition. We investigated imitation recognition in 11 individuals from the four species of non-human great apes. We replicated results previously found with a chimpanzee [7] and, critically, have extended them to the other great ape species. Our results show a general prevalence of imitation recognition in all great apes and thereby demonstrate important differences between great apes and monkeys in their understanding of contingent social interactions.

Abstract

Cranial growth and development is a complex process which affects the closely related traits of head circumference (HC) and intracranial volume (ICV). The underlying genetic influences affecting these traits during the transition from childhood to adulthood are little understood, but might include both age-specific genetic influences and low-frequency genetic variation. To understand these influences, we model the developmental genetic architecture of HC, showing this is genetically stable and correlated with genetic determinants of ICV. Investigating up to 46,000 children and adults of European descent, we identify association with final HC and/or final ICV+HC at 9 novel common and low-frequency loci, illustrating that genetic variation from a wide allele frequency spectrum contributes to cranial growth. The largest effects are reported for low-frequency variants within TP53, with 0.5 cm wider heads in increaser-allele carriers versus non-carriers during mid-childhood, suggesting a previously unrecognized role of TP53 transcripts in human cranial development.

Abstract

Background
Autism and different neurodevelopmental conditions frequently co-occur, as do their symptoms at sub-diagnostic threshold levels. Overlapping traits and shared genetic liability are potential explanations.

Methods
In the population-based Norwegian Mother, Father, and Child Cohort study (MoBa), we leverage item-level data to explore the phenotypic factor structure and genetic architecture underlying neurodevelopmental traits at age 3 years (N = 41,708–58,630) using maternal reports on 76 items assessing children’s motor and language development, social functioning, communication, attention, activity regulation, and flexibility of behaviors and interests.

Results
We identified 11 latent factors at the phenotypic level. These factors showed associations with diagnoses of autism and other neurodevelopmental conditions. Most shared genetic liabilities with autism, ADHD, and/or schizophrenia. Item-level GWAS revealed trait-specific genetic correlations with autism (items rg range = − 0.27–0.78), ADHD (items rg range = − 0.40–1), and schizophrenia (items rg range = − 0.24–0.34). We find little evidence of common genetic liability across all neurodevelopmental traits but more so for several genetic factors across more specific areas of neurodevelopment, particularly social and communication traits. Some of these factors, such as one capturing prosocial behavior, overlap with factors found in the phenotypic analyses. Other areas, such as motor development, seemed to have more heterogenous etiology, with specific traits showing a less consistent pattern of genetic correlations with each other.

Conclusions
These exploratory findings emphasize the etiological complexity of neurodevelopmental traits at this early age. In particular, diverse associations with neurodevelopmental conditions and genetic heterogeneity could inform follow-up work to identify shared and differentiating factors in the early manifestations of neurodevelopmental traits and their relation to autism and other neurodevelopmental conditions. This in turn could have implications for clinical screening tools and programs.

Abstract

Rare disruptions of the transcription factor FOXP1 are implicated in a human neurodevelopmental disorder characterized by autism and/or intellectual disability with prominent problems in speech and language abilities. Avian orthologues of this transcription factor are evolutionarily conserved and highly expressed in specific regions of songbird brains, including areas associated with vocal production learning and auditory perception. Here, we investigated possible contributions of FoxP1 to song discrimination and auditory perception in juvenile and adult female zebra finches. They received lentiviral knockdowns of FoxP1 in one of two brain areas involved in auditory stimulus processing, HVC (proper name) or CMM (caudomedial mesopallium). Ninety-six females, distributed over different experimental and control groups were trained to discriminate between two stimulus songs in an operant Go/Nogo paradigm and subsequently tested with an array of stimuli. This made it possible to assess how well they recognized and categorized altered versions of training stimuli and whether localized FoxP1 knockdowns affected the role of different features during discrimination and categorization of song. Although FoxP1 expression was significantly reduced by the knockdowns, neither discrimination of the stimulus songs nor categorization of songs modified in pitch, sequential order of syllables or by reversed playback were affected. Subsequently, we analyzed the full dataset to assess the impact of the different stimulus manipulations for cue weighing in song discrimination. Our findings show that zebra finches rely on multiple parameters for song discrimination, but with relatively more prominent roles for spectral parameters and syllable sequencing as cues for song discrimination.

NEW & NOTEWORTHY In humans, mutations of the transcription factor FoxP1 are implicated in speech and language problems. In songbirds, FoxP1 has been linked to male song learning and female preference strength. We found that FoxP1 knockdowns in female HVC and caudomedial mesopallium (CMM) did not alter song discrimination or categorization based on spectral and temporal information. However, this large dataset allowed to validate different cue weights for spectral over temporal information for song recognition.

Abstract

While rhythm can facilitate and enhance many aspects of behavior, its evolutionary trajectory in vocal communication systems remains enigmatic. We can trace evolutionary processes by investigating rhythmic abilities in different species, but research to date has largely focused on songbirds and primates. We present evidence that cetaceans—whales, dolphins, and porpoises—are a missing piece of the puzzle for understanding why rhythm evolved in vocal communication systems. Cetaceans not only produce rhythmic vocalizations but also exhibit behaviors known or thought to play a role in the evolution of different features of rhythm. These behaviors include vocal learning abilities, advanced breathing control, sexually selected vocal displays, prolonged mother–infant bonds, and behavioral synchronization. The untapped comparative potential of cetaceans is further enhanced by high interspecific diversity, which generates natural ranges of vocal and social complexity for investigating various evolutionary hypotheses. We show that rhythm (particularly isochronous rhythm, when sounds are equally spaced in time) is prevalent in cetacean vocalizations but is used in different contexts by baleen and toothed whales. We also highlight key questions and research areas that will enhance understanding of vocal rhythms across taxa. By coupling an infraorder-level taxonomic assessment of vocal rhythm production with comparisons to other species, we illustrate how broadly comparative research can contribute to a more nuanced understanding of the prevalence, evolution, and possible functions of rhythm in animal communication.