Publications

Abstract

Electrophysiological studies consistently find N400 effects of semantic incongruity in nonnative (L2) language comprehension. These N400 effects are often delayed compared with native (L1) comprehension, suggesting that semantic integration in one's second language occurs later than in one's first language. In this study, we investigated whether such a delay could be attributed to (1) intralingual lexical competition and/or (2) interlingual lexical competition. We recorded EEG from Dutch–English bilinguals who listened to English (L2) sentences in which the sentence-final word was (a) semantically fitting and (b) semantically incongruent or semantically incongruent but initially congruent due to sharing initial phonemes with (c) the most probable sentence completion within the L2 or (d) 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 but not to L1 translation equivalents that were initially congruent with the sentence context. Taken together, these findings firstly demonstrate that semantic integration in nonnative listening can start based on word initial phonemes (i.e., before a single lexical candidate could have been selected based on the input) and secondly suggest that spuriously elicited L1 lexical candidates are not available for semantic integration in L2 speech comprehension.

Abstract

Research papers, Bressanone conference on psycholinguistics, summer courses of the University of Padova, July 1969

Abstract

This dissertation is an ethnographic study of race and other forms of social categorization as approached through the discourse of the indigenous Chachi people of northwestern lowland Ecuador and their Afro-descendant neighbors. It combines the ethnographic methods of social anthropology with the methods of descriptive linguistics, letting social questions about racial formation guide linguistic inquiry. It provides new information about the largely unstudied indigenous South American language Cha’palaa, and connects that information about linguistic form to problems of the study of race and ethnicity in Latin America. Individual descriptive chapters address how the Cha’palaa number system is based on collectivity rather than plurality according to an animacy hierarchy that codes only human and human-like social collectivities, how a nominal set of ethnonyms linked to Chachi oral history become the recipients of collective marking as human collectivities, how those collectivities are co-referentially linked to speech participants through the deployment of the pronominal system, and how the multi-modal resource of gesture adds to these rich resources supplied by the spoken language for the expression of social realities like race. The final chapters address Chachi and Afrodescendant discourses in dialogue with each other and examine naturally occurring speech data to show how the linguistic forms described in previous chapters are used in social interaction. The central argument advances a position that takes the socially constructed status of race seriously and considers that for such constructions to exist as more abstract macro-categories they must be constituted by instances of social interaction, where elements of the social order are observable at the micro-level. In this way localized articulations of social categories become vehicles for the broader circulation of discourses structured by a history of racialized social inequality, revealing the extreme depth of racialization in human social conditioning. This dissertation represents a contribution to the field of linguistic anthropology as well as to descriptive linguistics of South American languages and to critical approaches to race and ethnicity in Latin America.

Abstract

This article briefly reviews some recent work on artificial language learning in children and adults. The final part of the article is devoted to a theoretical formulation of the language learning problem from a mechanistic neurobiological viewpoint and we show that it is logically possible to combine the notion of innate language constraints with, for example, the notion of domain general learning mechanisms. A growing body of empirical evidence suggests that the mechanisms involved in artificial language learning and in structured sequence processing are shared with those of natural language acquisition and natural language processing. Finally, by theoretically analyzing a formal learning model, we highlight Fodor’s insight that it is logically possible to combine innate, domain-specific constraints with domain-general learning mechanisms.

Abstract

Accurate reconstruction of prehistoric social organization is important if we are to put together satisfactory multidisciplinary scenarios about, for example, the dispersal of human groups. Such considerations apply in the case of Indo-European and Austronesian, two large-scale language families that are thought to represent Neolithic expansions. Ancestral kinship patterns have mostly been inferred through reconstruction of kin terminologies in ancestral proto-languages using the linguistic comparative method, and through geographical or distributional arguments based on the comparative patterns of kin terms and ethnographic kinship ‘facts’. While these approaches are detailed and valuable, the processes through which conclusions have been drawn from the data fail to provide explicit criteria for systematic testing of alternative hypotheses. Here, we use language trees derived using phylogenetic tree-building techniques on Indo-European and Austronesian vocabulary data. With these trees, ethnographic data and Bayesian phylogenetic comparative methods, we statistically reconstruct past marital residence and infer rates of cultural change between different residence forms, showing Proto-Indo-European to be virilocal and Proto-Malayo-Polynesian uxorilocal. The instability of uxorilocality and the rare loss of virilocality once gained emerge as common features of both families

Abstract

An MEG experiment was carried out in order to compare the processing of lexical-tonal and intonational contrasts, based on the tonal dialect of Roermond (the Netherlands). A set of words with identical phoneme sequences but distinct pitch contours, which represented different lexical meanings or discourse meanings (statement vs. question), were presented to native speakers as well as to a control group of speakers of Standard Dutch, a non-tone language. The stimuli were arranged in a mismatch paradigm, under three experimental conditions: in the first condition (lexical), the pitch contour differences between standard and deviant stimuli reflected differences between lexical meanings; in the second condition (intonational), the stimuli differed in their discourse meaning; in the third condition (combined), they differed both in their lexical and discourse meaning. In all three conditions, native as well as non-native responses showed a clear MMNm (magnetic mismatch negativity) in a time window from 150 to 250 ms after the divergence point of standard and deviant pitch contours. In the lexical condition, a stronger response was found over the left temporal cortex of native as well as non-native speakers. In the intonational condition, the same activation pattern was observed in the control group, but not in the group of native speakers, who showed a right-hemisphere dominance instead. Finally, in the combined (lexical and intonational) condition, brain reactions appeared to represent the summation of the patterns found in the other two conditions. In sum, the lateralization of pitch processing is condition-dependent in the native group only, which suggests that language experience determines how processes should be distributed over both temporal cortices, according to the functions available in the grammar.

Abstract

The aim of this study was to clarify whether audiovisual processing accounted for variance in reading and reading-related abilities, beyond the effect of a set of measures typically associated with individual differences in both reading and audiovisual processing. Testing adults with and without a diagnosis of dyslexia, we showed that—across all participants, and after accounting for variance in cognitive abilities—audiovisual temporal sensitivity contributed uniquely to variance in reading errors. This is consistent with previous studies demonstrating an audiovisual deficit in dyslexia. Additionally, we showed that speechreading (identification of speech based on visual cues from the talking face alone) was a unique contributor to variance in phonological awareness in dyslexic readers only: those who scored higher on speechreading, scored lower on phonological awareness. This suggests a greater reliance on visual speech as a compensatory mechanism when processing auditory speech is problematic. A secondary aim of this study was to better understand the nature of dyslexia. The finding that a sub-group of dyslexic readers scored low on phonological awareness and high on speechreading is consistent with a hybrid perspective of dyslexia: There are multiple possible pathways to reading impairment, which may translate into multiple profiles of dyslexia.

Abstract

Purpose: Because reading is an audiovisual process, reading impairment may reflect an audiovisual processing deficit. The aim of the present study was to test the existence and scope of such a deficit in adult readers with dyslexia. Method: We tested 39 typical readers and 51 adult readers with dyslexia on their sensitivity to the simultaneity of audiovisual speech and nonspeech stimuli, their time window of audiovisual integration for speech (using incongruent /aCa/ syllables), and their audiovisual perception of phonetic categories. Results: Adult readers with dyslexia showed less sensitivity to audiovisual simultaneity than typical readers for both speech and nonspeech events. We found no differences between readers with dyslexia and typical readers in the temporal window of integration for audiovisual speech or in the audiovisual perception of phonetic categories. Conclusions: The results suggest an audiovisual temporal deficit in dyslexia that is not specific to speech-related events. But the differences found for audiovisual temporal sensitivity did not translate into a deficit in audiovisual speech perception. Hence, there seems to be a hiatus between simultaneity judgment and perception, suggesting a multisensory system that uses different mechanisms across tasks. Alternatively, it is possible that the audiovisual deficit in dyslexia is only observable when explicit judgments about audiovisual simultaneity are required

Abstract

Population-based linkage analysis is a new method for analysing genomewide single nucleotide polymorphism (SNP) genotype data in case-control samples, which does not assume a common disease, common variant model. The genome is scanned for extended segments that show increased identity-by-descent sharing within case-case pairs, relative to case-control or control-control pairs. The method is robust to allelic heterogeneity and is suited to mapping genes which contain multiple, rare susceptibility variants of relatively high penetrance. We analysed genomewide SNP datasets for two schizophrenia case-control cohorts, collected in Aberdeen (461 cases, 459 controls) and Munich (429 cases, 428 controls). Population-based linkage testing must be performed within homogeneous samples and it was therefore necessary to analyse the cohorts separately. Each cohort was first subjected to several procedures to improve genetic homogeneity, including identity-by-state outlier detection and multidimensional scaling analysis. When testing only cases who reported a positive family history of major psychiatric disease, consistent with a model of strongly penetrant susceptibility alleles, we saw a distinct peak on chromosome 19q in both cohorts that appeared in meta-analysis (P=0.000016) to surpass the traditional level for genomewide significance for complex trait linkage. The linkage signal was also present in a third case-control sample for familial bipolar disorder, such that meta-analysing all three datasets together yielded a linkage P=0.0000026. A model of rare but highly penetrant disease alleles may be more applicable to some instances of major psychiatric diseases than the common disease common variant model, and we therefore suggest that other genome scan datasets are analysed with this new, complementary method.

Abstract

The ideal of scientific progress is that we accumulate measurements and integrate these into theory, but recent discussion of replicability issues has cast doubt on whether psychological research conforms to this model. Developmental research—especially with infant participants—also has discipline-specific replicability challenges, including small samples and limited measurement methods. Inspired by collaborative replication efforts in cognitive and social psychology, we describe a proposal for assessing and promoting replicability in infancy research: large-scale, multi-laboratory replication efforts aiming for a more precise understanding of key developmental phenomena. The ManyBabies project, our instantiation of this proposal, will not only help us estimate how robust and replicable these phenomena are, but also gain new theoretical insights into how they vary across ages, linguistic communities, and measurement methods. This project has the potential for a variety of positive outcomes, including less-biased estimates of theoretically important effects, estimates of variability that can be used for later study planning, and a series of best-practices blueprints for future infancy research.

Abstract

We investigate the effects of two types of relationship between the words of a sentence or text – predictability and semantic similarity – by reanalysing electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data from studies in which participants comprehend naturalistic stimuli. Each content word's predictability given previous words is quantified by a probabilistic language model, and semantic similarity to previous words is quantified by a distributional semantics model. Brain activity time-locked to each word is regressed on the two model-derived measures. Results show that predictability and semantic similarity have near identical N400 effects but are dissociated in the fMRI data, with word predictability related to activity in, among others, the visual word-form area, and semantic similarity related to activity in areas associated with the semantic network. This indicates that both predictability and similarity play a role during natural language comprehension and modulate distinct cortical regions.

Abstract

Attention deficit/hyperactivity disorder (ADHD) is one of the most common neuropsychiatric disorders with a worldwide prevalence around 4–5% in children and 1–4% in adults. Although ADHD is highly heritable and familial risk may contribute most strongly to the persistent form of the disorder, there are few studies on the genetics of ADHD in adults. In this paper, we present the first results of the International Multicentre Persistent ADHD Genetics CollaboraTion (IMpACT) that has been set up with the goal of performing research into the genetics of persistent ADHD. In this study, we carried out a combined analysis as well as a meta-analysis of the association of the SLC6A3/DAT1 gene with persistent ADHD in 1440 patients and 1769 controls from IMpACT and an earlier report. DAT1, encoding the dopamine transporter, is one of the most frequently studied genes in ADHD, though results have been inconsistent. A variable number tandem repeat polymorphism (VNTR) in the 3′-untranslated region (UTR) of the gene and, more recently, a haplotype of this VNTR with another VNTR in intron 8 have been the target of most studies. Although the 10/10 genotype of the 3′-UTR VNTR and the 10-6 haplotype of the two VNTRs are thought to be risk factors for ADHD in children, we found the 9/9 genotype and the 9-6 haplotype associated with persistent ADHD. In conclusion, a differential association of DAT1 with ADHD in children and in adults might help explain the inconsistencies observed in earlier association studies. However, the data might also imply that DAT1 has a modulatory rather than causative role in ADHD.

Abstract

One of the most daunting tasks of a listener is to map a
continuous auditory stream onto known speech sound
categories and lexical items. A major issue with this mapping
problem is the variability in the acoustic realizations of sound
categories, both within and across speakers. Past research has
suggested listeners may use visual information (e.g., lipreading)
to calibrate these speech categories to the current
speaker. Previous studies have focused on audiovisual
recalibration of consonant categories. The present study
explores whether vowel categorization, which is known to show
less sharply defined category boundaries, also benefit from
visual cues.
Participants were exposed to videos of a speaker
pronouncing one out of two vowels, paired with audio that was
ambiguous between the two vowels. After exposure, it was
found that participants had recalibrated their vowel categories.
In addition, individual variability in audiovisual recalibration is
discussed. It is suggested that listeners’ category sharpness may
be related to the weight they assign to visual information in
audiovisual speech perception. Specifically, listeners with less
sharp categories assign more weight to visual information
during audiovisual speech recognition.

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

An important part of understanding speech motor control consists of capturing the
interaction between speech production and speech perception. This study tests a
prediction of theoretical frameworks that have tried to account for these interactions: if
speech production targets are specified in auditory terms, individuals with better
auditory acuity should have more precise speech targets, evidenced by decreased
within-phoneme variability and increased between-phoneme distance. A study was
carried out consisting of perception and production tasks in counterbalanced order.
Auditory acuity was assessed using an adaptive speech discrimination task, while
production variability was determined using a pseudo-word reading task. Analyses of
the production data were carried out to quantify average within-phoneme variability as
well as average between-phoneme contrasts. Results show that individuals not only
vary in their production and perceptual abilities, but that better discriminators have
more distinctive vowel production targets (that is, targets with less within-phoneme
variability and greater between-phoneme distances), confirming the initial hypothesis.
This association between speech production and perception did not depend on local
phoneme density in vowel space. This study suggests that better auditory acuity leads
to more precise speech production targets, which may be a consequence of auditory
feedback affecting speech production over time.

Abstract

To identify genetic variants associated with birth weight, we meta-analyzed six genome-wide association (GWA) studies (n = 10,623 Europeans from pregnancy/birth cohorts) and followed up two lead signals in 13 replication studies (n = 27,591). rs900400 near LEKR1 and CCNL1 (P = 2 x 10(-35)) and rs9883204 in ADCY5 (P = 7 x 10(-15)) were robustly associated with birth weight. Correlated SNPs in ADCY5 were recently implicated in regulation of glucose levels and susceptibility to type 2 diabetes, providing evidence that the well-described association between lower birth weight and subsequent type 2 diabetes has a genetic component, distinct from the proposed role of programming by maternal nutrition. Using data from both SNPs, we found that the 9% of Europeans carrying four birth weight-lowering alleles were, on average, 113 g (95% CI 89-137 g) lighter at birth than the 24% with zero or one alleles (P(trend) = 7 x 10(-30)). The impact on birth weight is similar to that of a mother smoking 4-5 cigarettes per day in the third trimester of pregnancy.

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

Neurons derived from human induced Pluripotent Stem Cells (hiPSCs) provide a promising new tool for studying neurological disorders. In the past decade, many protocols for differentiating hiPSCs into neurons have been developed. However, these protocols are often slow with high variability, low reproducibility, and low efficiency. In addition, the neurons obtained with these protocols are often immature and lack adequate functional activity both at the single-cell and network levels unless the neurons are cultured for several months. Partially due to these limitations, the functional properties of hiPSC-derived neuronal networks are still not well characterized. Here, we adapt a recently published protocol that describes production of human neurons from hiPSCs by forced expression of the transcription factor neurogenin-212. This protocol is rapid (yielding mature neurons within 3 weeks) and efficient, with nearly 100% conversion efficiency of transduced cells (>95% of DAPI-positive cells are MAP2 positive). Furthermore, the protocol yields a homogeneous population of excitatory neurons that would allow the investigation of cell-type specific contributions to neurological disorders. We modified the original protocol by generating stably transduced hiPSC cells, giving us explicit control over the total number of neurons. These cells are then used to generate hiPSC-derived neuronal networks on micro-electrode arrays. In this way, the spontaneous electrophysiological activity of hiPSC-derived neuronal networks can be measured and characterized, while retaining interexperimental consistency in terms of cell density. The presented protocol is broadly applicable, especially for mechanistic and pharmacological studies on human neuronal networks.

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

Achieving linguistic proficiency requires identifying words from speech, and discovering the constraints that govern the way those words are used. In a recent study of non-adjacent dependency learning, Frost and Monaghan (2016) demonstrated that learners may perform these tasks together, using similar statistical processes - contrary to prior suggestions. However, in their study, non-adjacent dependencies were marked by phonological cues (plosive-continuant-plosive structure), which may have influenced learning. Here, we test the necessity of these cues by comparing learning across three conditions; fixed phonology, which contains these cues, varied phonology, which omits them, and shapes, which uses visual shape sequences to assess the generality of statistical processing for these tasks. Participants segmented the sequences and generalized the structure in both auditory conditions, but learning was best when phonological cues were present. Learning was around chance on both tasks for the visual shapes group, indicating statistical processing may critically differ across domains.

Abstract

Speech segmentation is supported by multiple sources of information that may either inform language processing specifically, or serve learning more broadly. The Iambic/Trochaic Law (ITL), where increased duration indicates the end of a group and increased emphasis indicates the beginning of a group, has been proposed as a domain-general mechanism that also applies to language. However, language background has been suggested to modulate use of the ITL, meaning that these perceptual grouping preferences may instead be a consequence of language exposure. To distinguish between these accounts, we exposed native-English and native-Japanese listeners to sequences of speech (Experiment 1) and nonspeech stimuli (Experiment 2), and examined segmentation using a 2AFC task. Duration was manipulated over 3 conditions: sequences contained either an initial-item duration increase, or a final-item duration increase, or items of uniform duration. In Experiment 1, language background did not affect the use of duration as a cue for segmenting speech in a structured artificial language. In Experiment 2, the same results were found for grouping structured sequences of visual shapes. The results are consistent with proposals that duration information draws upon a domain-general mechanism that can apply to the special case of language acquisition

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

Acquiring language requires segmenting speech into individual words, and abstracting over those words to discover grammatical structure. However, these tasks can be conflicting—on the one hand requiring memorisation of precise sequences that occur in speech, and on the other requiring a flexible reconstruction of these sequences to determine the grammar. Here, we examine whether speech segmentation and generalisation of grammar can occur simultaneously—with the conflicting requirements for these tasks being over-come by sleep-related consolidation. After exposure to an artificial language comprising words containing non-adjacent dependencies, participants underwent periods of consolidation involving either sleep or wake. Participants who slept before testing demonstrated a sustained boost to word learning and a short-term improvement to grammatical generalisation of the non-adjacencies, with improvements after sleep outweighing gains seen after an equal period of wake. Thus, we propose that sleep may facilitate processing for these conflicting tasks in language acquisition, but with enhanced benefits for speech segmentation.

Abstract

A crucial aspect of everyday conversational interactions is our ability to establish and maintain common ground. Understanding the relevant mechanisms involved in such social coordination remains an important challenge for cognitive science. While common ground is often discussed in very general terms, different contexts of interaction are likely to afford different coordination mechanisms. In this paper, we investigate the presence and relation of three mechanisms of social coordination – backchannels, interactive alignment and conversational repair – across free and task-oriented conversations. We find significant differences: task-oriented conversations involve higher presence of repair – restricted offers in particular – and backchannel, as well as a reduced level of lexical and syntactic alignment. We find that restricted repair is associated with lexical alignment and open repair with backchannels. Our findings highlight the need to explicitly assess several mechanisms at once and to investigate diverse activities to understand their role and relations.

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

Large-scale graph data in real-world applications is often not static but dynamic,
i. e., new nodes and edges appear over time. Current graph convolution approaches
are promising, especially, when all the graph’s nodes and edges are available dur-
ing training. When unseen nodes and edges are inserted after training, it is not
yet evaluated whether up-training or re-training from scratch is preferable. We
construct an experimental setup, in which we insert previously unseen nodes and
edges after training and conduct a limited amount of inference epochs. In this
setup, we compare adapting pretrained graph neural networks against retraining
from scratch. Our results show that pretrained models yield high accuracy scores
on the unseen nodes and that pretraining is preferable over retraining from scratch.
Our experiments represent a first step to evaluate and develop truly online variants
of graph neural networks.

Abstract

We conduct the first systematic comparison of automated semantic
annotation based on either the full-text or only on the title metadata
of documents. Apart from the prominent text classification baselines
kNN and SVM, we also compare recent techniques of Learning
to Rank and neural networks and revisit the traditional methods
logistic regression, Rocchio, and Naive Bayes. Across three of our
four datasets, the performance of the classifications using only titles
reaches over 90% of the quality compared to the performance when
using the full-text.

Abstract

We assess the suitability of word embeddings for practical information retrieval scenarios. Thus, we assume that users issue ad-hoc short queries where we return the first twenty retrieved documents after applying a boolean matching operation between the query and the documents. We compare the performance of several techniques that leverage word embeddings in the retrieval models to compute the similarity between the query and the documents, namely word centroid similarity, paragraph vectors, Word Mover’s distance, as well as our novel inverse document frequency (IDF) re-weighted word centroid similarity. We evaluate the performance using the ranking metrics mean average precision, mean reciprocal rank, and normalized discounted cumulative gain. Additionally, we inspect the retrieval models’ sensitivity to document length by using either only the title or the full-text of the documents for the retrieval task. We conclude that word centroid similarity is the best competitor to state-of-the-art retrieval models. It can be further improved by re-weighting the word frequencies with IDF before aggregating the respective word vectors of the embedding. The proposed cosine similarity of IDF re-weighted word vectors is competitive to the TF-IDF baseline and even outperforms it in case of the news domain with a relative percentage of 15%.

Abstract

As the popularity of sending messages electronically increases, so does the necessity of conveying messages more efficiently. One way of increasing efficiency is to abbreviate words and expressions by combining letters with numbers such as gr8 for “great,” using acronyms, such as lol for “laughing out loud,” or clippings such as msg for “message.” The present study compares the processing of shortcuts to the processing of closely matched pseudo-shortcuts. ERPs were recorded while participants were performing a lexical decision task. Response times showed that shortcuts were categorized more slowly as nonwords than pseudo-shortcuts. The ERP results showed no differences between shortcuts and pseudo-shortcuts at time windows 50–150 ms and 150–270 ms, but there were significant differences between 270 and 500 ms. These results suggest that at early stages of word recognition, the orthographic and phonological processing is similar for shortcuts and pseudo-shortcuts. However, at the time of lexical access, shortcuts diverge from pseudo-shortcuts, suggesting that shortcuts activate stored lexical representations.

Abstract

The current event-related brain potential study examined the processing of observed speech errors.
Participants were asked to detect errors in the speech of others while listening to the description of a visual
network. Networks consisted of colored drawings of objects connected by straight or curved lines. We
investigated the processing of two types of errors in the network descriptions, i.e., incorrect color and errors
in determiners usage (gender agreement violations). In the 100- to 300-ms and 300- to 550-ms time
windows, we found larger PMN and N400 amplitudes for both color and determiner error trials compared to
correct trials. Furthermore, color but not determiner errors led to larger P600 amplitudes compared to
correct color trials. Color errors also showed enhanced P600 amplitudes compared to determiner errors.
Taken together, processing erroneous network descriptions elicits different brain potentials than listening to
the corresponding correct utterances. Hence, speech is monitored for errors not only during speech
production but also during listening to the naturally occurring speech of others.

Abstract

For efficiency reasons, words in electronic messages are sometimes formed by combining letters with numbers, as in gr8 for “great.” The aim of this study was to investigate whether a digit incorporated into a letter—digit shortcut would retain its numerosity. A priming paradigm was used with letter—digit shortcuts (e.g., gr8) and matched pseudoshortcuts (e.g., qr8) as primes. The primes were presented simultaneously with sets of dots (targets) for which even/odd decisions were required, or they appeared 250 msec before target onset. When pseudoshortcuts were presented, decision latencies were shorter when the target and the digit in the prime were matched in parity than when they were mismatched. This main effect of match was not significant for shortcuts. The results suggest that the number concepts of digits combined with letters become activated but are quickly suppressed or deactivated when the digit is part of an existing shortcut.

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

Manatees live in shallow, frequently turbid
waters. The sensory means by which they navigate in these
conditions are unknown. Poor visual acuity, lack of echo-
location, and modest chemosensation suggest that other
modalities play an important role. Rich innervation of sen-
sory hairs that cover the entire body and enlarged soma-
tosensory areas of the brain suggest that tactile senses are
good candidates. Previous tests of detection of underwater
vibratory stimuli indicated that they use passive movement
of the hairs to detect particle displacements in the vicinity
of a micron or less for frequencies from 10 to 150 Hz. In
the current study, hydrodynamic stimuli were created by
a sinusoidally oscillating sphere that generated a dipole
field at frequencies from 5 to 150 Hz. Go/no-go tests of
manatee postcranial mechanoreception of hydrodynamic
stimuli indicated excellent sensitivity but about an order of
magnitude less than the facial region. When the vibrissae
were trimmed, detection thresholds were elevated, suggest-
ing that the vibrissae were an important means by which
detection occurred. Manatees were also highly accurate in two-choice directional discrimination: greater than 90%
correct at all frequencies tested. We hypothesize that mana-
tees utilize vibrissae as a three-dimensional array to detect
and localize low-frequency hydrodynamic stimuli

Abstract

Heterozygous mutations of the human FOXP2 gene are implicated in a severe speech and language disorder. Aetiological mutations of murine Foxp2 yield abnormal synaptic plasticity and impaired motor-skill learning in mutant mice, while knockdown of the avian orthologue in songbirds interferes with auditory-guided vocal learning. Here, we investigate influences of two distinct Foxp2 point mutations on vocalizations of 4-day-old mouse pups (Mus musculus). The R552H missense mutation is identical to that causing speech and language deficits in a large well-studied human family, while the S321X nonsense mutation represents a null allele that does not produce Foxp2 protein. We ask whether vocalizations, based solely on innate mechanisms of production, are affected by these alternative Foxp2 mutations. Sound recordings were taken in two different situations: isolation and distress, eliciting a range of call types, including broadband vocalizations of varying noise content, ultrasonic whistles and clicks. Sound production rates and several acoustic parameters showed that, despite absence of functional Foxp2, homozygous mutants could vocalize all types of sounds in a normal temporal pattern, but only at comparably low intensities. We suggest that altered vocal output of these homozygotes may be secondary to developmental delays and somatic weakness. Heterozygous mutants did not differ from wild-types in any of the measures that we studied (R552H ) or in only a few (S321X ), which were in the range of differences routinely observed for different mouse strains. Thus, Foxp2 is not essential for the innate production of emotional vocalizations with largely normal acoustic properties by mouse pups.

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

An endophenotype for attention deficit/hyperactivity disorder (AD/HD) is executive functioning. In the autism and developmental literature executive dysfunctions has also been linked to theory of mind (ToM) and pragmatic language use. The central question of this review is whether deficits in ToM and pragmatic language use are common in AD/HD. AD/HD seems to be associated with pragmatic deficits, but not with ToM deficits. In this review we address how this pattern of findings might facilitate the understanding of the commonalities and differences between executive functioning, ToM, and pragmatic abilities. Based on the reviewed studies we conclude that ToM is not likely to be a potential endophenotype for AD/HD, while it is too early to draw such a conclusion for pragmatic language use.

Abstract

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

Abstract

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

Neuroimaging measures provide useful endophenotypes for tracing genetic effects on reading and language. A recent Genome-Wide Association Scan Meta-Analysis (GWASMA) of reading and language skills (N = 1862) identified strongest associations with the genes CCDC136/FLNC and RBFOX2. Here, we follow up the top findings from this GWASMA, through neuroimaging genetics in an independent sample of 1275 healthy adults. To minimize multiple-testing, we used a multivariate approach, focusing on cortical regions consistently implicated in prior literature on developmental dyslexia and language impairment. Specifically, we investigated grey matter surface area and thickness of five regions selected a priori: middle temporal gyrus (MTG); pars opercularis and pars triangularis in the inferior frontal gyrus (IFG-PO and IFG-PT); postcentral parietal gyrus (PPG) and superior temporal gyrus (STG). First, we analysed the top associated polymorphisms from the reading/language GWASMA: rs59197085 (CCDC136/FLNC) and rs5995177 (RBFOX2). There was significant multivariate association of rs5995177 with cortical thickness, driven by effects on left PPG, right MTG, right IFG (both PO and PT), and STG bilaterally. The minor allele, previously associated with reduced reading-language performance, showed negative effects on grey matter thickness. Next, we performed exploratory gene-wide analysis of CCDC136/FLNC and RBFOX2; no other associations surpassed significance thresholds. RBFOX2 encodes an important neuronal regulator of alternative splicing. Thus, the prior reported association of rs5995177 with reading/language performance could potentially be mediated by reduced thickness in associated cortical regions. In future, this hypothesis could be tested using sufficiently large samples containing both neuroimaging data and quantitative reading/language scores from the same individuals.

Abstract

BACKGROUND: It is unclear to what extent non-clinical psychotic experiences during childhood and adolescence share underlying aetiological mechanisms with schizophrenia. One candidate mechanism for schizophrenia involves the epigenetic status of the developing fetus, which depends on the internal folate-status of mother and child. Our study examines the relationships between multiple determinants of perinatal folate-status and development of psychotic experiences in adolescence. METHODS: Study participants were up to 5344 mother-child pairs from the Avon Longitudinal Study of Parents and their Children, UK, with information on maternal and/or child MTHFR C677T genotype, maternal folate intake (supplementation at 18/32- weeks gestation; dietary intake at 32- weeks gestation) and psychosis-like symptoms (PLIKS) for children assessed at age 12. RESULTS: Nominal evidence was observed that maternal folate supplementation at 18 weeks increased the odds of PLIKS in children (odds ratio(OR)=1.34; 95%-CI:[1.00;1.76]) and, consistent with this, that children of MTHFR C667T TT homozygous mothers had decreased odds of PLIKS (OR=0.72; 95%CI:[0.50;1.02]; recessive model) with strongest effects in boys (OR=0.44, 95%-CI:[0.22;0.79]; sex-specific p=0.029). None of the reported effects remained significant when corrected for multiple testing. CONCLUSIONS: Overall, this study found no support that maternal/child MTHFR C677T genotype and maternal folate intake during pregnancy contribute to common aetiological pathways that are shared between schizophrenia and non-clinical psychotic symptoms in adolescents, assuming that decreased folate-status increases schizophrenia risk.

Abstract

PURPOSE: Conduct problems and peer effects are among the strongest risk factors for adolescent substance use and problem use. However, it is unclear to what extent the effects of conduct problems and peer behavior interact, and whether adolescents' capacity to refuse the offer of substances may moderate such links. This study was conducted to examine relationships between conduct problems, close friends' substance use, and refusal assertiveness with adolescents' alcohol use problems, tobacco, and marijuana use. METHODS: We studied a population-based sample of 1,237 individuals from the Cardiff Study of All Wales and North West of England Twins aged 11-18 years. Adolescent and mother-reported information was obtained. Statistical analyses included cross-sectional and prospective logistic regression models and family-based permutations. RESULTS: Conduct problems and close friends' substance use were associated with increased adolescents' substance use, whereas refusal assertiveness was associated with lower use of cigarettes, alcohol, and marijuana. Peer substance use moderated the relationship between conduct problems and alcohol use problems, such that conduct problems were only related to increased risk for alcohol use problems in the presence of substance-using friends. This effect was found in both cross-sectional and prospective analyses and confirmed using the permutation approach. CONCLUSIONS: Reduced opportunities for interaction with alcohol-using peers may lower the risk of alcohol use problems in adolescents with conduct problems.

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

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

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

Synaesthesia is the neuropsychological phenomenon in which individuals experience unusual sensory associations, such as experiencing particular colours in response to particular words. While it was once thought the particular pairings between stimuli were arbitrary and idiosyncratic to particular synaesthetes, there is now growing evidence for a systematic psycholinguistic basis to the associations. Here we sought to assess the explanatory value of quantifiable lexical association measures (via latent semantic analysis; LSA) in the pairings observed between words and colours in synaesthesia. To test this, we had synaesthetes report the particular colours they experienced in response to given concept words, and found that language association between the concept and colour words provided highly reliable predictors of the reported pairings. These results provide convergent evidence for a psycholinguistic basis to synaesthesia, but in a novel way, showing that exposure to particular patterns of associations in language can predict the formation of particular synaesthetic lexical-colour associations. Consistent with previous research, the prototypical synaesthetic colour for the first letter of the word also played a role in shaping the colour for the whole word, and this effect also interacted with language association, such that the effect of the colour for the first letter was stronger as the association between the concept word and the colour word in language increased. Moreover, when a group of non-synaesthetes were asked what colours they associated with the concept words, they produced very similar reports to the synaesthetes that were predicted by both language association and prototypical synaesthetic colour for the first letter of the word. This points to a shared linguistic experience generating the associations for both groups.

Abstract

This paper presents the Demo / Kemo corpus of Dutch and Korean emotional speech. The corpus has been specifically developed for the purpose of cross-linguistic comparison, and is more balanced than any similar corpus available so far: a) it contains expressions by both Dutch and Korean actors as well as judgments by both Dutch and Korean listeners; b) the same elicitation technique and recording procedure was used for recordings of both languages; c) the same nonsense sentence, which was constructed to be permissible in both languages, was used for recordings of both languages; and d) the emotions present in the corpus are balanced in terms of valence, arousal, and dominance. The corpus contains a comparatively large number of emotions (eight) uttered by a large number of speakers (eight Dutch and eight Korean). The counterbalanced nature of the corpus will enable a stricter investigation of language-specific versus universal aspects of emotional expression than was possible so far. Furthermore, given the carefully controlled phonetic content of the expressions, it allows for analysis of the role of specific phonetic features in emotional expression in Dutch and Korean.

Abstract

Background: Voluntarily opening or closing our eyes results in fundamentally different input patterns and expectancies. Yet it remains unclear how our brains and visual systems adapt to these ocular states.
Objective/Hypothesis: We here used transcranial magnetic stimulation (TMS) to probe the excitability of the human visual system with eyes open or closed, in the complete absence of visual inputs.
Methods: Combining Bayesian staircase procedures with computer control of TMS pulse intensity allowed interleaved determination of phosphene thresholds (PT) in both conditions. We measured parieto-occipital EEG baseline activity in several stages to track oscillatory power in the alpha (8-12 Hz) frequency-band, which has previously been shown to be inversely related to phosphene perception.
Results: Since closing the eyes generally increases alpha power, one might have expected a decrease in excitability (higher PT). While we confirmed a rise in alpha power with eyes closed, visual excitability was actually increased (PT was lower) with eyes closed.
Conclusions: This suggests that, aside from oscillatory alpha power, additional neuronal mechanisms influence the excitability of early visual cortex. One of these may involve a more internally oriented mode of brain operation, engaged by closing the eyes. In this state, visual cortex may be more susceptible to top-down inputs, to facilitate for example multisensory integration or imagery/working memory, although alternative explanations remain possible. (C) 2017 Elsevier Inc. All rights reserved.

Abstract

Perceiving the temporal order of sensory events typically depends on participants' attentional state, thus likely on the endogenous fluctuations of brain activity. Using magnetoencephalography, we sought to determine whether spontaneous brain oscillations could disambiguate the perceived order of auditory and visual events presented in close temporal proximity, that is, at the individual's perceptual order threshold (Point of Subjective Simultaneity [PSS]). Two neural responses were found to index an individual's temporal order perception when contrasting brain activity as a function of perceived order (i.e., perceiving the sound first vs. perceiving the visual event first) given the same physical audiovisual sequence. First, average differences in prestimulus auditory alpha power indicated perceiving the correct ordering of audiovisual events irrespective of which sensory modality came first: a relatively low alpha power indicated perceiving auditory or visual first as a function of the actual sequence order. Additionally, the relative changes in the amplitude of the auditory (but not visual) evoked responses were correlated with participant's correct performance. Crucially, the sign of the magnitude difference in prestimulus alpha power and evoked responses between perceived audiovisual orders correlated with an individual's PSS. Taken together, our results suggest that spontaneous oscillatory activity cannot disambiguate subjective temporal order without prior knowledge of the individual's bias toward perceiving one or the other sensory modality first. Altogether, our results suggest that, under high perceptual uncertainty, the magnitude of prestimulus alpha (de)synchronization indicates the amount of compensation needed to overcome an individual's prior in the serial ordering and temporal sequencing of information

Abstract

Jerome Seymour “Jerry” Bruner was born on October 1, 1915, in New York City. He began his academic career as psychology professor at Harvard University; he ended it as University Professor Emeritus at New York University (NYU) Law School. What happened at both ends and in between is the subject of the richly variegated remembrances that follow. On June 5, 2016, Bruner died in his Greenwich Village loft at age 100. He leaves behind his beloved partner Eleanor Fox, who was also his distinguished colleague at NYU Law School; his son Whitley; his daughter Jenny; and three grandchildren.

Bruner’s interdisciplinarity and internationalism are seen in the remarkable variety of disciplines and geographical locations represented in the following tributes. The reader will find developmental psychology, anthropology, computer science, psycholinguistics, cognitive psychology, cultural psychology, education, and law represented; geographically speaking, the writers are located in the United States, Canada, the United Kingdom, and the Netherlands. The memories that follow are arranged in roughly chronological order according to when the writers had their first contact with Jerry Bruner.

Abstract

Understanding how and why language subsystems differ in their evolutionary dynamics is a fundamental question for historical and comparative linguistics. One key dynamic is the rate of language change. While it is commonly thought that the rapid rate of change hampers the reconstruction of deep language relationships beyond 6,000–10,000 y, there are suggestions that grammatical structures might retain more signal over time than other subsystems, such as basic vocabulary. In this study, we use a Dirichlet process mixture model to infer the rates of change in lexical and grammatical data from 81 Austronesian languages. We show that, on average, most grammatical features actually change faster than items of basic vocabulary. The grammatical data show less schismogenesis, higher rates of homoplasy, and more bursts of contact-induced change than the basic vocabulary data. However, there is a core of grammatical and lexical features that are highly stable. These findings suggest that different subsystems of language have differing dynamics and that careful, nuanced models of language change will be needed to extract deeper signal from the noise of parallel evolution, areal readaptation, and contact.

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

Multitasking requires individuals to allocate their cognitive resources across different tasks. The purpose of the current study was to assess school-age children’s multitasking abilities during degraded speech recognition. Children (8 to 12 years old) completed a dual-task paradigm including a sentence recognition (primary) task containing speech that was either unpro- cessed or noise-band vocoded with 8, 6, or 4 spectral channels and a visual monitoring (secondary) task. Children’s accuracy and reaction time on the visual monitoring task was quantified during the dual-task paradigm in each condition of the primary task and compared with single-task performance. Children experienced dual-task costs in the 6- and 4-channel conditions of the primary speech recognition task with decreased accuracy on the visual monitoring task relative to baseline performance. In all conditions, children’s dual-task performance on the visual monitoring task was strongly predicted by their single-task (baseline) performance on the task. Results suggest that children’s proficiency with the secondary task contributes to the magnitude of dual-task costs while multitasking during degraded speech recognition.

Abstract

Language in high-functioning autism is characterized by pragmatic and semantic deficits, and people with autism have a reduced tendency to integrate information. Because the left and right inferior frontal (LIF and RIF) regions are implicated with integration of speaker information, world knowledge, and semantic knowledge, we hypothesized that abnormal functioning of the LIF and RIF regions might contribute to pragmatic and semantic language deficits in autism. Brain activation of sixteen 12- to 18-year-old, high-functioning autistic participants was measured with functional magnetic resonance imaging during sentence comprehension and compared with that of twenty-six matched controls. The content of the pragmatic sentence was congruent or incongruent with respect to the speaker characteristics (male/female, child/adult, and upper class/lower class). The semantic- and world-knowledge sentences were congruent or incongruent with respect to semantic expectancies and factual expectancies about the world, respectively. In the semanticknowledge and world-knowledge condition, activation of the LIF region did not differ between groups. In sentences that required integration of speaker information, the autism group showed abnormally reduced activation of the LIF region. The results suggest that people with autism may recruit the LIF region in a different manner in tasks that demand integration of social information.

Abstract

Visual attention is biased by both visual and semantic representations activated by words. We investigated to what extent language-induced visual and semantic biases are subject to task demands. Participants memorized a spoken word for a verbal recognition task, and performed a visual search task during the retention period. Crucially, while the word had to be remembered in all conditions, it was either relevant for the search (as it also indicated the target) or irrelevant (as it only served the memory test afterwards). On critical trials, displays contained objects that were visually or semantically related to the memorized word. When the word was relevant for the search, eye movement biases towards visually related objects arose earlier and more strongly than biases towards semantically related objects. When the word was irrelevant, there was still evidence for visual and semantic biases, but these biases were substantially weaker, and similar in strength and temporal dynamics, without a visual advantage. We conclude that language-induced attentional biases are subject to task requirements.

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 two hemispheres of the human brain differ functionally and structurally. Despite over a century of research, the extent to which brain asymmetry is influenced by sex, handedness, age, and genetic factors is still controversial. Here we present the largest ever analysis of subcortical brain asymmetries, in a harmonized multi-site study using meta-analysis methods. Volumetric asymmetry of seven subcortical structures was assessed in 15,847 MRI scans from 52 datasets worldwide. There were sex differences in the asymmetry of the globus pallidus and putamen. Heritability estimates, derived from 1170 subjects belonging to 71 extended pedigrees, revealed that additive genetic factors influenced the asymmetry of these two structures and that of the hippocampus and thalamus. Handedness had no detectable effect on subcortical asymmetries, even in this unprecedented sample size, but the asymmetry of the putamen varied with age. Genetic drivers of asymmetry in the hippocampus, thalamus and basal ganglia may affect variability in human cognition, including susceptibility to psychiatric disorders.

Abstract

Researchers in human language processing and acquisition are making an increasing use of computational models. Computer simulations provide a valuable platform to reproduce hypothesised learning mechanisms that are otherwise very difficult, if not impossible, to verify on human subjects. However, computational models come with problems and risks. It is difficult to (automatically) extract essential information about the developing internal representations from a set of simulation runs, and often researchers limit themselves to analysing learning curves based on empirical recognition accuracy through time. The associated risk is to erroneously deem a specific learning behaviour as generalisable to human learners, while it could also be a mere consequence (artifact) of the implementation of the artificial learner or of the input coding scheme. In this paper a set of simulation runs taken from the ACORNS project is investigated. First a look `inside the box' of the learner is provided by employing novel quantitative methods for analysing changing structures in large data sets. Then, the obtained findings are discussed in the perspective of their ecological validity in the field of child language acquisition.

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 success of fMRI places constraints on the nature of the neural code. The fact that researchers can infer similarities between neural representations, despite fMRI’s limitations, implies that certain neural coding schemes are more likely than others. For fMRI to succeed given its low temporal and spatial resolution, the neural code must be smooth at the voxel and functional level such that similar stimuli engender similar internal representations. Through proof and simulation, we determine which coding schemes are plausible given both fMRI’s successes and its limitations in measuring neural activity. Deep neural network approaches, which have been forwarded as computational accounts of the ventral stream, are consistent with the success of fMRI, though functional smoothness breaks down in the later network layers. These results have implications for the nature of the neural code and ventral stream, as well as what can be successfully investigated with fMRI.

Abstract

Despite the literature on the role of input in adult second-language (L2) acquisition and on artificial and statistical language learning, surprisingly little is known about how adults break into a new language in the wild. This article reports on a series of behavioral and neuroimaging studies that examine what linguistic information adults can extract from naturalistic but controlled audiovisual input in an unknown and typologically distant L2 after minimal exposure (7–14 min) without instruction or training. We tested the stepwise development of segmental, phonotactic, and lexical knowledge in Dutch adults after minimal exposure to Mandarin Chinese and the role of item frequency, speech-associated gestures, and word length at the earliest stages of learning. In an exploratory neural connectivity study we further examined the neural correlates of word recognition in a new language, identifying brain regions whose connectivity was related to performance both before and after learning. While emphasizing the complexity of the learning task, the results suggest that the adult learning mechanism is more powerful than is normally assumed when faced with small amounts of complex, continuous audiovisual language input.

Abstract

Gestures are often regarded as the most typical compensatory device used by language learners in communicative trouble. Yet gestural solutions to communicative problems have rarely been studied within any theory of second language use. The work pre­sented in this volume aims to account for second language learners’ strategic use of speech-associated gestures by combining a process-oriented framework for communi­cation strategies with a cognitive theory of gesture. Two empirical studies are presented. The production study investigates Swedish lear­ners of French and French learners of Swedish and their use of strategic gestures. The results, which are based on analyses of both individual and group behaviour, contradict popular opinion as well as theoretical assumptions from both fields. Gestures are not primarily used to replace speech, nor are they chiefly mimetic. Instead, learners use gestures with speech, and although they do exploit mimetic gestures to solve lexical problems, they also use more abstract gestures to handle discourse-related difficulties and metalinguistic commentary. The influence of factors such as proficiency, task, culture, and strategic competence on gesture use is discussed, and the oral and gestural strategic modes are compared. In the evaluation study, native speakers’ assessments of learners’ gestures, and the potential effect of gestures on evaluations of proficiency are analysed and discussed in terms of individual communicative style. Compensatory gestures function at multiple communicative levels. This has implica­tions for theories of communication strategies, and an expansion of the existing frameworks is discussed taking both cognitive and interactive aspects into account.

Abstract

Gestures are prevalent in communication and tightly linked to language and speech. As such they can shed important light on issues of language development across the lifespan. This volume, originally published as a Special Issue of Gesture Volume 8:2 (2008), brings together studies from different disciplines that examine language development in children and adults from varying perspectives. It provides a review of common theoretical and empirical themes, and the contributions address topics such as gesture use in prelinguistic infants, the relationship between gestures and lexical development in typically and atypically developing children and in second language learners, what gestures reveal about discourse, and how all languages that adult second language speakers know can influence each other. The papers exemplify a vibrant new field of study with relevance for multiple disciplines.

Abstract

Gestures, the symbolic movements speakers perform while they speak, form a closely inter-connected system with speech where gestures serve both addressee-directed (‘communicative’) and speaker-directed (’internal’) functions. This paper aims (1) to show that a combined analysis of gesture and speech offers new ways to address theoretical issues in SLA and bilingualism studies, probing SLA and bilingualism as product and process; and (2) to outline some methodological concerns and desiderata to facilitate the inclusion of gesture in SLA and bilingualism research.

Abstract

To understand the nature of language learning, the factors that influence it, and the mechanisms that govern it, it is crucial to study the very earliest stages of language learning. This volume provides a state-of-the art overview of what we know about the cognitive and neurobiological aspects of the adult capacity for language learning. It brings together studies from several fields that examine learning from multiple perspectives using various methods. The papers examine learning after anything from a few minutes to months of language exposure; they target the learning of both artificial and natural languages, involve both explicit and implicit learning, and cover linguistic domains ranging from phonology and semantics to morphosyntax. The findings will inform and extend further studies of language learning in multiple disciplines.

Abstract

Placement verbs describe every-day events like putting a toy in a box. Dutch uses two semi-obligatory caused posture verbs (leggen ‘lay’ and zetten ‘set/stand’) to distinguish between events based on whether the located object is placed horizontally or vertically. Although prevalent in the input, these verbs cause Dutch children difficulties even at age five (Narasimhan & Gullberg, submitted). Children overextend leggen to all placement events and underextend use of zetten. This study examines what gestures can reveal about Dutch three- and five-year-olds’ semantic representations of such verbs. The results show that children gesture differently from adults in this domain. Three-year-olds express only the path of the caused motion, whereas five-year-olds, like adults, also incorporate the located object. Crucially, gesture patterns are tied to verb use: those children who over-use leggen 'lay' for all placement events only gesture about path. Conversely, children who use the two verbs differentially for horizontal and vertical placement also incorporate objects in gestures like adults. We argue that children's gestures reflect their current knowledge of verb semantics, and indicate a developmental transition from a system with a single semantic component – (caused) movement – to an (adult-like) focus on two semantic components – (caused) movement-and-object

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

Acceptability judgments are no longer acceptable as the holy grail for testing the nature of linguistic representations. Experimental and quantitative methods should be used to test theoretical claims in psycholinguistics. These methods should include not only behavior, but also the more recent possibilities to probe the neural codes for language-relevant representation

Abstract

In this paper a general cognitive architecture of spoken language processing is specified. This is followed by an account of how this cognitive architecture is instantiated in the human brain. Both the spatial aspects of the networks for language are discussed, as well as the temporal dynamics and the underlying neurophysiology. A distinction is proposed between networks for coding/decoding linguistic information and additional networks for getting from coded meaning to speaker meaning, i.e. for making the inferences that enable the listener to understand the intentions of the speaker

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

Reading is a cultural invention that needs to recruit cortical infrastructure that was not designed for it (cultural recycling of cortical maps). In the case of reading both visual cortex and networks for speech processing are recruited. Here I discuss current views on the neurobiological underpinnings of spoken language that deviate in a number of ways from the classical Wernicke-Lichtheim-Geschwind model. More areas than Broca’s and Wernicke’s region are involved in language. Moreover, a division along the axis of language production and language comprehension does not seem to be warranted. Instead, for central aspects of language processing neural infrastructure is shared between production and comprehension. Arguments are presented in favor of a dynamic network view, in which the functionality of a region is co-determined by the network of regions in which it is embedded at particular moments in time. Finally, core regions of language processing need to interact with other networks (e.g. the attentional networks and the ToM network) to establish full functionality of language and communication. The consequences of this architecture for reading are discussed.

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

Child songs are a great source for linguistic learning. Here we explore whether children can acquire novel words in a second language by playing a game featuring child songs in a playhouse. We present data from three studies that serve as scientific proof for the functionality of one game of the playhouse: the Energy Center. For this game, three hand-bikes were mounted on a panel. When children start moving the hand-bikes, child songs start playing simultaneously. Once the children produce enough energy with the hand-bikes, the songs are additionally accompanied with the sounds of musical instruments. In our studies, children executed a picture-selection task to evaluate whether they acquired new vocabulary from the songs presented during the game. Two of our studies were run in the field, one at a Dutch and one at an Indian pre-school. The third study features data from a more controlled laboratory setting. Our results partly confirm that the Energy Center is a successful means to support vocabulary acquisition in a second language. More research with larger sample sizes and longer access to the Energy Center is needed to evaluate the overall functionality of the game. Based on informal observations at our test sites, however, we are certain that children do pick up linguistic content from the songs during play, as many of the children repeat words and phrases from songs they heard. We will pick up upon these promising observations during future studies