Publications

Abstract

The molecular, developmental, and evolutionary bases of human brain asymmetry are almost completely unknown. Genetic linkage and association mapping have pin-pointed a gene called LRRTM1 (leucine-rich repeat transmembrane neuronal 1) that may contribute to variability in human handedness. Here I describe how LRRTM1's involvement in handedness was discovered, and also the latest knowledge of its functions in brain development and disease. The association of LRRTM1 with handedness was derived entirely from the paternally inherited gene, and follow-up analysis of gene expression confirmed that LRRTM1 is one of a small number of genes that are imprinted in the human genome, for which the maternally inherited copy is suppressed. The same variation at LRRTM1 that was associated paternally with mixed-/left-handedness was also over-transmitted paternally to schizophrenic patients in a large family study.
LRRTM1 is expressed in specific regions of the developing and adult forebrain by post-mitotic neurons, and the protein may be involved in axonal trafficking. Thus LRRTM1 has a probable role in neurodevelopment, and its association with handedness suggests that one of its functions may be in establishing or consolidating human brain asymmetry.
LRRTM1 is the first gene for which allelic variation has been associated with human handedness. The genetic data also suggest indirectly that the epigenetic regulation of this gene may yet prove more important than DNA sequence variation for influencing brain development and disease.
Intriguingly, the parent-of-origin activity of LRRTM1 suggests that men and women have had conflicting interests in relation to the outcome of lateralized brain development in their offspring.

Abstract

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

Abstract

Francks et al. (2007) performed a recent study in which the first putative genetic effect on human handedness was identified (the imprinted locus LRRTM1 on human chromosome 2). In this issue of Laterality, Tim Crow and colleagues present a critique of that study. The present paper presents a personal response to that critique which argues that Francks et al. (2007) published a substantial body of evidence implicating LRRTM1 in handedness and schizophrenia. Progress will now be achieved by others trying to validate, refute, or extend those findings, rather than by further armchair discussion.

Abstract

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

Abstract

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

Abstract

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

Abstract

This research exploits the English and Dutch CELEX lexical database to investigate the form similarity relations between words. Lexical statistics analyses replicate and extend the findings of Landauer and Streeter (1973) concerning the relation between a word′s frequency and the density and frequency of its similarity neighborhood. The results for both Dutch and English reveal only a weak tendency for high-frequency written and spoken words to have more neighbors than rare words and for these neighbors to be more frequent than those of rare words. However, the number of neighbors was found to correlate more highly with bigram frequency than with word frequency. To clarify the relations between these properties, a stochastic model is presented which captures the relevant effects of phonotactic structure on neighborhood similarities. The implications of these findings for models of language production and comprehension are considered.

Abstract

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

Abstract

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

Abstract

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

Abstract

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

Abstract

This study addresses how verbal self-monitoring and the Error-Related Negativity (ERN) are affected by time pressure
when a task is performed in a second language as opposed to performance in the native language. German–Dutch
bilinguals were required to perform a phoneme-monitoring task in Dutch with and without a time pressure manipulation.
We obtained an ERN following verbal errors that showed an atypical increase in amplitude under time
pressure. This finding is taken to suggest that under time pressure participants had more interference from their native
language, which in turn led to a greater response conflict and thus enhancement of the amplitude of the ERN. This
result demonstrates once more that the ERN is sensitive to psycholinguistic manipulations and suggests that the
functioning of the verbal self-monitoring systemduring speaking is comparable to other performance monitoring, such
as action monitoring.

Abstract

Phonagnosia, the inability to recognize familiar voices, has been studied in brain-damaged patients but no cases due to developmental problems have been reported. Here we describe the case of KH, a 60-year-old active professional woman who reports that she has always experienced severe voice recognition difficulties. Her hearing abilities are normal, and an MRI scan showed no evidence of brain damage in regions associated with voice or auditory perception. To better understand her condition and to assess models of voice and high-level auditory processing, we tested KH on behavioural tasks measuring voice recognition, recognition of vocal emotions, face recognition, speech perception, and processing of environmental sounds and music. KH was impaired on tasks requiring the recognition of famous voices and the learning and recognition of new voices. In contrast, she performed well on nearly all other tasks. Her case is the first report of developmental phonagnosia, and the results suggest that the recognition of a speaker’s vocal identity depends on separable mechanisms from those used to recognize other information from the voice or non-vocal auditory stimuli.

Abstract

In the context of large and ever growing archives, generating annotation suggestions automatically from textual resources related to the documents to be archived is an interesting option in theory. It could save a lot of work in the time consuming and expensive task of manual annotation and it could help cataloguers attain a higher inter-annotator agreement. However, some questions arise in practice: what is the quality of the automatically produced annotations? How do they compare with manual annotations and with the requirements for annotation that were defined in the archive? If different from the manual annotations, are the automatic annotations wrong? In the CHOICE project, partially hosted at the Netherlands Institute for Sound and Vision, the Dutch public archive for audiovisual broadcasts, we automatically generate annotation suggestions for cataloguers. In this paper, we define three types of evaluation of these annotation suggestions: (1) a classic and strict evaluation measure expressing the overlap between automatically generated keywords and the manual annotations, (2) a loosened evaluation measure for which semantically very similar annotations are also considered as relevant matches, and (3) an in-use evaluation of the usefulness of manual versus automatic annotations in the context of serendipitous browsing. During serendipitous browsing, the annotations (manual or automatic) are used to retrieve and visualize semantically related documents.

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

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

Abstract

OBJECTIVES: Combining the analysis of family-based samples with unrelated individuals can enhance the power of genetic association studies. Various combined analysis techniques have been recently developed; as yet, there have been no comparisons of their power, or robustness to confounding factors. We investigated empirically the power of up to six combined methods using simulated samples of trios and unrelated cases/controls (TDTCC), trios and unrelated controls (TDTC), and affected sibpairs with parents and unrelated cases/controls (ASPFCC). METHODS: We simulated multiplicative, dominant and recessive models with varying risk parameters in single samples. Additionally, we studied false-positive rates and investigated, if possible, the coverage of the true genetic effect (TDTCC). RESULTS/CONCLUSIONS: Under the TDTCC design, we identified four approaches with equivalent power and false-positive rates. Combined statistics were more powerful than single-sample statistics or a pooled chi(2)-statistic when risk parameters were similar in single samples. Adding parental information to the CC part of the joint likelihood increased the power of generalised logistic regression under the TDTC but not the TDTCC scenario. Formal testing of differences between risk parameters in subsamples was the most sensitive approach to avoid confounding in combined analysis. Non-parametric analysis based on Monte-Carlo testing showed the highest power for ASPFCC samples.

Abstract

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

Abstract

The verb has traditionally been characterized as the central element in a sentence. Nevertheless, the exact role of the verb during the actual ongoing comprehension of a sentence as it unfolds in time remains largely unknown. This paper reports the results of two Cross-Modal Lexical Priming (CMLP) experiments detailing the pattern of verb priming during on-line processing of Dutch sentences. Results are contrasted with data from a third CMLP experiment on priming of nouns in similar sentences. It is demonstrated that the meaning of a matrix verb remains active throughout the entire matrix clause, while this is not the case for the meaning of a subject head noun. Activation of the meaning of the verb only dissipates upon encountering a clear signal as to the start of a new clause.

Abstract

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

Abstract

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

Abstract

Learning to recognize the contrasts of a language-specific phonemic repertoire can be viewed as forming categories in a multidimensional psychophysical space. Research on the learning of distributionally defined visual categories has shown that categories defined over I dimension are easy to learn and that learning multidimensional categories is more difficult but tractable under specific task conditions. In 2 experiments, adult participants learned either a unidimensional ora multidimensional category distinction with or without supervision (feedback) during learning. The unidimensional distinctions were readily learned and supervision proved beneficial, especially in maintaining category learning beyond the learning phase. Learning the multidimensional category distinction proved to be much more difficult and supervision was not nearly as beneficial as with unidimensionally defined categories. Maintaining a learned multidimensional category distinction was only possible when the distributional information (hat identified the categories remained present throughout the testing phase. We conclude that listeners are sensitive to both trial-by-trial feedback and the distributional information in the stimuli. Even given limited exposure, listeners learned to use 2 relevant dimensions. albeit with considerable difficulty.

Abstract

Prolectin, a previously undescribed glycan-binding receptor, has been identified by re-screening of the human genome for genes encoding proteins containing potential C-type carbohydrate-recognition domains. Glycan array analysis revealed that the carbohydrate-recognition domain in the extracellular domain of the receptor binds glycans with terminal α-linked mannose or fucose residues. Prolectin expressed in fibroblasts is found at the cell surface, but unlike many glycan-binding receptors it does not mediate endocytosis of a neoglycoprotein ligand. However, compared with other known glycan-binding receptors, the receptor contains an unusually large intracellular domain that consists of multiple sequence motifs, including phosphorylated tyrosine residues, that allow it to interact with signaling molecules such as Grb2. Immunohistochemistry has been used to demonstrate that prolectin is expressed on a specialized population of proliferating B cells in germinal centers. Thus, this novel receptor has the potential to function in carbohydrate-mediated communication between cells in the germinal center.

Abstract

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

Abstract

To understand the underlying principles of categorisation and classification of sensory input semantic analyses must be based on both language and culture. The senses are not only physiological phenomena, but they are also linguistic, cultural, and social. The goal of this task is to explore and describe sociocultural patterns relating language of perception, ideologies of perception, and perceptual practice in our speech communities.

Abstract

The goal of this task is to investigate cross-cultural emotion categories in language and thought. This entry is designed to provide researchers with some guidelines to describe the emotional repertoire of a community from an emic perspective. The first objective is to offer ethnographic tools and a questionnaire in order to understand the semantics of emotional terms and the local conception of emotions. The second objective is to identify the local display rules of emotions in communicative interactions.

Abstract

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

Abstract

There is growing evidence that addressees in interaction integrate the semantic information conveyed by speakers’ gestures. Little is known, however, about whether and how addressees’ attention to gestures and the integration of gestural information can be modulated. This study examines the influence of a social factor (speakers’ gaze to their own gestures), and two physical factors (the gesture’s location in gesture space and gestural holds) on addressees’ overt visual attention to gestures (direct fixations of gestures) and their uptake of gestural information. It also examines the relationship between gaze and uptake. The results indicate that addressees’ overt visual attention to gestures is affected both by speakers’ gaze and holds but for different reasons, whereas location in space plays no role. Addressees’ uptake of gesture information is only influenced by speakers’ gaze. There is little evidence of a direct relationship between addressees’ direct fixations of gestures and their uptake.

Abstract

This chapter explores what L2 learners' gestures reveal about L2 grammar. The focus is on learners’ difficulties with maintaining reference in discourse caused by their incomplete mastery of pronouns. The study highlights the systematic parallels between properties of L2 speech and gesture, and the parallel effects of grammatical development in both modalities. The validity of a communicative account of interlanguage grammar in this domain is tested by taking the cohesive properties of the gesture-speech ensemble into account. Specifically, I investigate whether learners use gestures to compensate for and to license over-explicit reference in speech. The results rule out a communicative account for the spoken variety of maintained reference. In contrast, cohesive gestures are found to be multi-functional. While the presence of cohesive gestures is not communicatively motivated, their spatial realisation is. It is suggested that gestures are exploited as a grammatical communication strategy to disambiguate speech wherever possible, but that they may also be doing speaker-internal work. The methodological importance of considering L2 gestures when studying grammar is also discussed.

Abstract

Gestures, the symbolic movements speakers perform while they speak, are systematically related to speech and language at multiple levels, and reflect cognitive and linguistic activities in non-trivial ways. This chapter presents an overview of what gestures can tell us about the processes of second language acquisition. It focuses on two key aspects, (a) gestures and the developing language system and (b) gestures and learning, and discusses some implications of an expanded view of language acquisition that takes gestures into account.

Abstract

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

Abstract

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

Abstract

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

Abstract

This paper argues that speech-associated gestures can usefully inform studies exploring development of meaning in first and second language acquisition. The example domain is caused motion or placement meaning (putting a cup on a table) where acquisition problems have been observed and where adult native gesture use reflects crosslinguistically different placement verb semantics. Against this background, the paper summarises three studies examining the development of semantic representations in Dutch children acquiring Dutch, and adult learners’ acquiring Dutch and French placement verbs. Overall, gestures change systematically with semantic development both in children and adults and (1) reveal what semantic elements are included in current semantic representations, whether target-like or not, and (2) highlight developmental shifts in those representations. There is little evidence that gestures chiefly act as a support channel. Instead, the data support the theoretical notion that speech and gesture form an integrated system, opening new possibilities for studying the processes of acquisition.

Abstract

Since listeners usually look at the speaker's face, gestural information has to be absorbed through peripheral visual perception. In the literature, it has been suggested that listeners look at gestures under certain circumstances: 1) when the articulation of the gesture is peripheral; 2) when the speech channel is insufficient for comprehension; and 3) when the speaker him- or herself indicates that the gesture is worthy of attention. The research here reported employs eye tracking techniques to study the perception of gestures in face-to-face interaction. The improved control over the listener's visual channel allows us to test the validity of the above claims. We present preliminary findings substantiating claims 1 and 3, and relate them to theoretical proposals in the literature and to the issue of how visual and cognitive attention are related.

Abstract

This study examines to what extent English speakers of L2 Dutch reconstruct the meanings of placement verbs when moving from a general L1 verb of caused motion (put) to two specific caused posture verbs (zetten/leggen ‘set/lay’) in the L2 and whether the existence of low-frequency cognate forms in the L1 (set/lay) alleviates the reconstruction problem. Evidence from speech and gesture indicates that English speakers have difficulties with the specific verbs in L2 Dutch, initially looking for means to express general caused motion in L1-like fashion through over-generalisation. The gesture data further show that targetlike forms are often used to convey L1-like meaning. However, the differentiated use of zetten for vertical placement and dummy verbs (gaan ‘go’ and doen ‘do’) and intransitive posture verbs (zitten/staan/liggen ‘sit, stand, lie’) for horizontal placement, and a positive correlation between appropriate verb use and target-like gesturing suggest a beginning sensitivity to the semantic parameters of the L2 verbs and possible reconstruction.

Abstract

The aim of this chapter is to provide researchers with a tool kit of semi-experimental and experimental techniques for studying code-switching. It presents an overview of the current off-line and on-line research techniques, ranging from analyses of published bilingual texts of spontaneous conversations, to tightly controlled experiments. A multi-task approach used for studying code-switched sentence production in Papiamento-Dutch bilinguals is also exemplified.

Abstract

Gestures, the symbolic movements speakers perform while they speak, are systematically related to speech and language in non-trivial ways. This chapter presents an overview of what gestures can and cannot tell us about the monolingual and the bilingual mental lexicon. Gesture analysis opens for a broader view of the mental lexicon, targeting the interface between conceptual, semantic and syntactic aspects of event construal, and offers new possibilities for examining how languages co-exist and interact in bilinguals beyond the level of surface forms. The first section of this chapter gives a brief introduction to gesture studies and outlines the current views on the relationship between gesture, speech, and language. The second section targets the key questions for the study of the monolingual and bilingual lexicon, and illustrates the methods employed for addressing these questions. It further exemplifies systematic cross-linguistic patterns in gestural behaviour in monolingual and bilingual contexts. The final section discusses some implications of an expanded view of the multilingual lexicon that includes gesture, and outlines directions for future inquiry.

Abstract

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

Abstract

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

Abstract

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

Abstract

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

Abstract

The central issue of this study concerns the claim that the processing of gender agreement in online sentence comprehension is a syntactic rather than a conceptual/semantic process. This claim was tested for the grammatical gender agreement in Dutch between the definite article and the noun. Subjects read sentences in which the definite article and the noun had the same gender and sentences in which the gender agreement was violated, While subjects read these sentences, their electrophysiological activity was recorded via electrodes placed on the scalp. Earlier research has shown that semantic and syntactic processing events manifest themselves in different event-related brain potential (ERP) effects. Semantic integration modulates the amplitude of the so-called N400.The P600/SPS is an ERP effect that is more sensitive to syntactic processes. The violation of grammatical gender agreement was found to result in a P600/SPS. For violations in sentence-final position, an additional increase of the N400 amplitude was observed. This N400 effect is interpreted as resulting from the consequence of a syntactic violation for the sentence-final wrap-up. The overall pattern of results supports the claim that the on-line processing of gender agreement information is not a content driven but a syntactic-form driven process.

Abstract

Broca′s and Wernicke′s aphasics performed speeded lexical decisions on the third member of auditorily presented triplets consisting of two word primes followed by either a word or a nonword. In three of the four priming conditions, the second prime was a homonym with two unrelated meanings. The relation of the first prime and the target with the two meanings of the homonym was manipulated in the different priming conditions. The two readings of the ambiguous words either shared their grammatical form class (noun-noun ambiguities) or not (noun-verb ambiguities). The silent intervals between the members of the triplets were varied between 100, 500, and 1250 msec. Priming at the shortest interval is mainly attributed to automatic lexical processing, and priming at the longest interval is mainly due to forms of controlled lexical processing. For both Broca′s and Wernicke′s aphasics overall priming effects were obtained at ISIs of 100 and 500 msec, but not at an ISI of 1250 msec. This pattern of results is consistent with the view that both types of aphasics can automatically access the semantic lexicon, but might be impaired in integrating lexical-semantic information into the context. Broca′s aphasics showed a specific impairment in selecting the contextually appropriate reading of noun-verb ambiguities, which is suggested to result from a failure either in the on-line morphological parsing of complex word forms into a stem and an inflection or in the on-line exploitation of the syntactic implications of the inflectional suffix. In a final experiment patients were asked to explicitly judge the semantic relations between a subset of the primes that were used in the lexical decision study. Wernicke′s aphasics performed worse than both Broca′s aphasics and normal controls, indicating a specific impairment for these patients in consciously operating on automatically accessed lexical-semantic information.

Abstract

This contribution focuses on the neural infrastructure for parsing and syntactic encoding. From an anatomical point of view, it is argued that Broca's area is an ill-conceived notion. Functionally, Broca's area and adjacent cortex (together Broca's complex) are relevant for language, but not exclusively for this domain of cognition. Its role can be characterized as providing the necessary infrastructure for unification (syntactic and semantic). A general proposal, but with required level of computational detail, is discussed to account for the distribution of labor between different components of the language network in the brain.Arguments are provided for the immediacy principle, which denies a privileged status for syntax in sentence processing. The temporal profile of event-related brain potential (ERP) is suggested to require predictive processing. Finally, since, next to speed, diversity is a hallmark of human languages, the language readiness of the brain might not depend on a universal, dedicated neural machinery for syntax, but rather on a shaping of the neural infrastructure of more general cognitive systems (e.g., memory, unification) in a direction that made it optimally suited for the purpose of communication through language.

Abstract

Language and communication are about the exchange of meaning. A key feature of understanding and producing language is the construction of complex meaning from more elementary semantic building blocks. The functional characteristics of this semantic unification process are revealed by studies using event related brain potentials. These studies have found that word meaning is assembled into compound meaning in not more than 500 ms. World knowledge, information about the speaker, co-occurring visual input and discourse all have an immediate impact on semantic unification, and trigger similar electrophysiological responses as sentence-internal semantic information. Neuroimaging studies show that a network of brain areas, including the left inferior frontal gyrus, the left superior/middle temporal cortex, the left inferior parietal cortex and, to a lesser extent their right hemisphere homologues are recruited to perform semantic unification.

Abstract

How does intention to speak become the action of speaking? It involves the generation of a preverbal message that is tailored to the requirements of a particular language, and through a series of steps, the message is transformed into a linear sequence of speech sounds (1, 2). These steps include retrieving different kinds of information from memory (semantic, syntactic, and phonological), and combining them into larger structures, a process called unification. Despite general agreement about the steps that connect intention to articulation, there is no consensus about their temporal profile or the role of feedback from later steps (3, 4). In addition, since the discovery by the French physician Pierre Paul Broca (in 1865) of the role of the left inferior frontal cortex in speaking, relatively little progress has been made in understanding the neural infrastructure that supports speech production (5). One reason is that the characteristics of natural language are uniquely human, and thus the neurobiology of language lacks an adequate animal model. But on page 445 of this issue, Sahin et al. (6) demonstrate, by recording neuronal activity in the human brain, that different kinds of linguistic information are indeed sequentially processed within Broca's area.

Abstract

This paper presents event-related brain potential (ERP) data from an experiment on syntactic processing. Subjects read individual sentences containing one of three different kinds of violations of the syntactic constraints of Dutch. The ERP results provide evidence for M electrophysiological response to syntactic processing that is qualitatively different from established ERP responses to semantic processing. We refer to this electro-physiological manifestation of parsing as the Syntactic Positive Shift (SPS). The SPS was observed in an experiment in which no task demands, other than to read the input, were imposed on the subjects. The pattern of responses to the different kinds of syntactic violations suggests that the SPS indicates the impossibility for the parser to assign the preferred structure to an incoming string of words, irrespective of the specific syntactic nature of this preferred structure. The implications of these findings for further research on parsing are discussed.

Abstract

Silent reading and reading aloud of German words and pseudowords were used in a PET study using (15O)butanol to examine the neural correlates of reading and of the phonological conversion of legal letter strings, with or without meaning.
The results of 11 healthy, right-handed volunteers in the age range of 25 to 30 years showed activation of the lingual gyri during silent reading in comparison with viewing a fixation cross. Comparisons between the reading of words and pseudowords suggest the involvement of the middle temporal gyri in retrieving both the phonological and semantic code for words. The reading of pseudowords activates the left inferior frontal gyrus, including the ventral part of Broca’s area, to a larger extent than the reading of words. This suggests that this area might be involved in the sublexical conversion of orthographic input strings into phonological output codes. (Pre)motor areas were found to be activated during both silent reading and reading aloud. On the basis of the obtained activation patterns, it is hypothesized that the articulation of high-frequency syllables requires the retrieval of their concomitant articulatory gestures from the SMA and that the articulation of lowfrequency syllables recruits the left medial premotor cortex.

Abstract

Beim Sprechen und beim Sprachverstehen findet man die Wortbedeutung im Gedächtnis auf und kombiniert sie zu größeren Einheiten (Unifikation). Solche Unifikations-Operationen laufen auf unterschiedlichen Ebenen der Sprachverarbeitung ab. In diesem Beitrag wird ein Rahmen vorgeschlagen, in dem psycholinguistische Modelle mit neurobiologischer Sprachbetrachtung in Verbindung gebracht werden. Diesem Vorschlag zufolge spielt der linke inferiore frontale Gyrus (LIFG) eine bedeutende Rolle bei der Unifi kation

Abstract

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

Abstract

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

Abstract

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

Abstract

Two experiments were carried out to examine the syllable affiliation of intervocalic consonant clusters and their effects on speech segmentation in two different languages. In a syllable reversal task, Slovak and German speakers divided bisyllabic non-words that were presented aurally into two parts, starting with the second syllable. Following the maximal onset principle, intervocalic consonants should be maximally assigned to the onset of the following syllable in conformity with language-specific restrictions, e.g., /du.gru/, /zu.kro:/ (dot indicates a syllable boundary). According to German phonology, syllables require branching rhymes (hence, /zuk.ro:/). In Slovak, both /du.gru/ and /dug.ru/ are possible syllabifications. Experiment 1 showed that German speakers more often closed the first syllable (/zuk.ro:/), following the requirement for a branching rhyme. In Experiment 2, Slovak speakers showed no clear preference; the first syllable was either closed (/dug.ru/) or open (/du.gru/). Correlation analyses on previously conducted word-spotting studies (Hanulíková, in press, 2008) suggest that speech segmentation is unaffected by these syllabification preferences.

Abstract

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

Abstract

Recognizing relational similarity relies on the ability to understand that defining object properties might not lie in the objects individually, but in the relations of the properties of various object to each other. This aptitude is highly relevant for many important human skills such as language, reasoning, categorization and understanding analogy and metaphor. In the current study, we investigated the ability to recognize relational similarities by testing five species of great apes, including human children in a spatial task. We found that all species performed better if related elements are connected by logico-causal as opposed to non-causal relations. Further, we find that only children above 4 years of age, bonobos and chimpanzees, unlike younger children, gorillas and orangutans display some mastery of reasoning by non-causal relational similarity. We conclude that recognizing relational similarity is not in its entirety unique to the human species. The lack of a capability for language does not prohibit recognition of simple relational similarities. The data are discussed in the light of the phylogenetic tree of relatedness of the great apes.

Abstract

There has been considerable controversy over the existence of cognitive differences across human cultures: some claim that human cognition is essentially universal [1,2], others that it reflects cultural specificities [3,4]. One domain of interest has been spatial cognition [5,6]. Despite the global universality of physical space, cultures vary as to how space is coded in their language. Some, for example, do not use egocentric ‘left, right, front, back’ constructions to code spatial relations, instead using allocentric notions like ‘north, south, east, west’ [4,6]: “The spoon is north of the bowl!” Whether or not spatial cognition also varies across cultures remains a contested question [7,8]. Here we investigate whether memory for movements of one's own body differs between cultures with contrastive strategies for coding spatial relations. Our results show that the ways in which we memorize movements of our own body differ in line with culture-specific preferences for how to conceive of spatial relations.

Abstract

The results of two self-paced reading experiments are reported, which investigated the on-line processing of subject-object ambiguities in Dutch relative clause constructions like Dat is de vrouw die de meisjes heeft/hebben gezien by German advanced second language (L2) learners of Dutch. Native speakers of both Dutch and German have been shown to have a preference for a subject versus an object reading of such temporarily ambiguous sentences, and so we provided an ideal opportunity for the transfer of first language (L1) processing preferences to take place. We also investigated whether the participants' working memory span would affect their processing of the experimental items. The results suggest that processing decisions may be affected by working memory when task demands are high and in this case, the high working memory span learners patterned like the native speakers of lower working memory. However, when reading for comprehension alone, and when only structural information was available to guide parsing decisions, working memory span had no effect on the L2 learners' on-line processing, and this differed from the native speakers' even though the L1 and the L2 are highly comparable.

Abstract

Speech comprehension is resistant to acoustic distortion in the input, reflecting listeners' ability to adjust perceptual processes to match the speech input. This adjustment is reflected in improved comprehension of distorted speech with experience. For noise vocoding, a manipulation that removes spectral detail from speech, listeners' word report showed a significantly greater improvement over trials for listeners that heard clear speech presentations before rather than after hearing distorted speech (clear-then-distorted compared with distorted-then-clear feedback, in Experiment 1). This perceptual learning generalized to untrained words suggesting a sublexical locus for learning and was equivalent for word and nonword training stimuli (Experiment 2). These findings point to the crucial involvement of phonological short-term memory and top-down processes in the perceptual learning of noise-vocoded speech. Similar processes may facilitate comprehension of speech in an unfamiliar accent or following cochlear implantation.

Abstract

Objective: To evaluate cognitive outcome in adult survivors of bacterial meningitis. Methods: Data from three prospective multicentre studies were pooled and reanalysed, involving 155 adults surviving bacterial meningitis (79 after pneumococcal and 76 after meningococcal meningitis) and 72 healthy controls. Results: Cognitive impairment was found in 32% of patients and this proportion was similar for survivors of pneumococcal and meningococcal meningitis. Survivors of pneumococcal meningitis performed worse on memory tasks (p<0.001) and tended to be cognitively slower than survivors of meningococcal meningitis (p = 0.08). We found a diffuse pattern of cognitive impairment in which cognitive speed played the most important role. Cognitive performance was not related to time since meningitis; however, there was a positive association between time since meningitis and self-reported physical impairment (p<0.01). The frequency of cognitive impairment and the numbers of abnormal test results for patients with and without adjunctive dexamethasone were similar. Conclusions: Adult survivors of bacterial meningitis are at risk of cognitive impairment, which consists mainly of cognitive slowness. The loss of cognitive speed is stable over time after bacterial meningitis; however, there is a significant improvement in subjective physical impairment in the years after bacterial meningitis. The use of dexamethasone was not associated with cognitive impairment.

Abstract

Experiments 1 and 2 examined the time-course of retrieval of phonological, visual-shape and semantic knowledge as Dutch participants listened to sentences and looked at displays of four pictures. Given a sentence with beker, `beaker', for example, the display contained phonological (a beaver, bever), shape (a bobbin, klos), and semantic (a fork, vork) competitors. When the display appeared at sentence onset, fixations to phonological competitors preceded fixations to shape and semantic competitors. When display onset was 200 ms before (e.g.) beker, fixations were directed to shape and then semantic competitors, but not phonological competitors. In Experiments 3 and 4, displays contained the printed names of the previously-pictured entities; only phonological competitors were fixated preferentially. These findings suggest that retrieval of phonological, shape and semantic knowledge in the spoken-word and picture-recognition systems is cascaded, and that visual attention shifts are co-determined by the time-course of retrieval of all three knowledge types and by the nature of the information in the visual environment.

Abstract

Visual attention can be directed immediately, as a spoken word unfolds, towards conceptually related but nonassociated objects, even if they mismatch on other dimensions that would normally determine which objects in the scene were appropriate referents for the unfolding word (Huettig & Altmann, 2005). Here we demonstrate that the mapping between language and concurrent visual objects can also be mediated by visual-shape relations. On hearing "snake", participants directed overt attention immediately, within a visual display depicting four objects, to a picture of an electric cable, although participants had viewed the visual display with four objects for approximately 5 s before hearing the target word - sufficient time to recognize the objects for what they were. The time spent fixating the cable correlated significantly with ratings of the visual similarity between snakes in general and this particular cable. Importantly, with sentences contextually biased towards the concept snake, participants looked at the snake well before the onset of "snake", but they did not look at the visually similar cable until hearing "snake". Finally, we demonstrate that such activation can, under certain circumstances (e.g., during the processing of dominant meanings of homonyms), constrain the direction of visual attention even when it is clearly contextually inappropriate. We conclude that language-mediated attention can be guided by a visual match between spoken words and visual objects, but that such a match is based on lexical input and may not be modulated by contextual appropriateness.

Abstract

Two eyetracking experiments tested for activation of category coordinate and perceptually related concepts when speakers prepare the name of an object. Speakers saw four visual objects in a 2 × 2 array and identified and named a target picture on the basis of either category (e.g., "What is the name of the musical instrument?") or visual-form (e.g., "What is the name of the circular object?") instructions. There were more fixations on visual-form competitors and category coordinate competitors than on unrelated objects during name preparation, but the increased overt attention did not affect naming latencies. The data demonstrate that eye movements are a sensitive measure of the overlap between the conceptual (including visual-form) information that is accessed in preparation for word production and the conceptual knowledge associated with visual objects. Furthermore, these results suggest that semantic activation of competitor concepts does not necessarily affect lexical selection, contrary to the predictions of lexical-selection-by-competition accounts (e.g., Levelt, Roelofs, & Meyer, 1999).

Abstract

Ten healthy adults encountered pictures of unfamiliar archaic tools and successfully learned either their name, verbal definition of their usage, or both. Neural representation of the newly acquired information was probed with magnetoencephalography in an overt picture-naming task before and after learning, and in two categorization tasks after learning. Within 400 ms, activation proceeded from occipital through parietal to left temporal cortex, inferior frontal cortex (naming) and right temporal cortex (categorization). Comparison of naming of newly learned versus familiar pictures indicated that acquisition and maintenance of word forms are supported by the same neural network. Explicit access to newly learned phonology when such information was known strongly enhanced left temporal activation. By contrast, access to newly learned semantics had no comparable, direct neural effects. Both the behavioral learning pattern and neurophysiological results point to fundamentally different implementation of and access to phonological versus semantic features in processing pictured objects.

Abstract

Recent studies have detailed a remarkable degree of genetic and linguistic diversity in Northern Island Melanesia. Here we utilize that diversity to examine two models of genetic and linguistic coevolution. The first model predicts that genetic and linguistic correspondences formed following population splits and isolation at the time of early range expansions into the region. The second is analogous to the genetic model of isolation by distance, and it predicts that genetic and linguistic correspondences formed through continuing genetic and linguistic exchange between neighboring populations. We tested the predictions of the two models by comparing observed and simulated patterns of genetic variation, genetic and linguistic trees, and matrices of genetic, linguistic, and geographic distances. The data consist of 751 autosomal microsatellites and 108 structural linguistic features collected from 33 Northern Island Melanesian populations. The results of the tests indicate that linguistic and genetic exchange have erased any evidence of a splitting and isolation process that might have occurred early in the settlement history of the region. The correlation patterns are also inconsistent with the predictions of the isolation by distance coevolutionary process in the larger Northern Island Melanesian region, but there is strong evidence for the process in the rugged interior of the largest island in the region (New Britain). There we found some of the strongest recorded correlations between genetic, linguistic, and geographic distances. We also found that, throughout the region, linguistic features have generally been less likely to diffuse across population boundaries than genes. The results from our study, based on exceptionally fine-grained data, show that local genetic and linguistic exchange are likely to obscure evidence of the early history of a region, and that language barriers do not particularly hinder genetic exchange. In contrast, global patterns may emphasize more ancient demographic events, including population splits associated with the early colonization of major world regions.

Abstract

This chapter investigates the fit of genetic, phenotypic, and linguistic data to two well-known models of population history. The first of these models, termed the population fissions model, emphasizes population splitting, isolation, and independent evolution. It predicts that genetic and linguistic data will be perfectly tree-like. The second model, termed isolation by distance, emphasizes genetic exchange among geographically proximate populations. It predicts a monotonic decline in genetic similarity with increasing geographic distance. While these models are overly simplistic, deviations from them were expected to provide important insights into the population history of northern Island Melanesia. The chapter finds scant support for either model because the prehistory of the region has been so complex. Nonetheless, the genetic and linguistic data are consistent with an early radiation of proto-Papuan speakers into the region followed by a much later migration of Austronesian speaking peoples. While these groups subsequently experienced substantial genetic and cultural exchange, this exchange has been insufficient to erase this history of separate migrations.

Abstract

This paper reports on ongoing research on the role of various kinds of potential substrate languages in the development of the semantic structures of Ndyuka (Eastern Suriname Creole). A set of 100 senses of noun, verb, and other lexemes in Ndyuka were compared with senses of corresponding lexemes in three kinds of languages of the former Slave Coast and Gold Coast areas, and immediately adjoining hinterland: (a) Gbe languages; (b) other Kwa languages, specifically Akan and Ga; (c) non-Kwa Niger-Congo languages. The results of this process provide some evidence for the importance of the Gbe languages in the formation of the Suriname creoles, but also for the importance of other languages, and for the areal nature of some of the collocations studied, rendering specific identification of a single substrate source impossible and inappropriate. These results not only provide information about the role of Gbe and other languages in the formation of Ndyuka, but also give evidence for effects of substrate languages spoken by late arrivals some time after the "founders" of a given creole-speaking society. The conclusions are extrapolated beyond Suriname to creole genesis generally.