Publications

Abstract

This paper discusses four experiments on Dutch which show that distinctive phonological features differ in their relevance for word recognition. The relevance of a feature for word recognition depends on its phonological stability, that is, the extent to which that feature is generally realized in accordance with its lexical specification in the relevant word position. If one feature value is uninformative, all values of that feature are less relevant for word recognition, with the least informative feature being the least relevant. Features differ in their relevance both in spoken and written word recognition, though the differences are more pronounced in auditory lexical decision than in self-paced reading.

Abstract

This study addresses the question to what extent the production of regular past tense forms in Dutch is a¤ected by analogical processes. We report an experiment in which native speakers of Dutch listened to existing regular verbs over headphones, and had to indicate which of the past tense allomorphs, te or de, was appropriate for these verbs. According to generative analyses, the choice between the two su‰xes is completely regular and governed by the underlying [voice]-specification of the stem-final segment. In this approach, no analogical e¤ects are expected. In connectionist and analogical approaches, by contrast, the phonological similarity structure in the lexicon is expected to a¤ect lexical processing. Our experimental results support the latter approach: all participants created more nonstandard past tense forms, produced more inconsistency errors, and responded more slowly for verbs with stronger analogical support for the nonstandard form.

Abstract

Acoustic duration and degree of vowel reduction are known to correlate with a word’s frequency of occurrence. The present study broadens the research on the role of frequency in speech production to voice assimilation. The test case was regressive voice assimilation in Dutch. Clusters from a corpus of read speech were more often perceived as unassimilated in lower-frequency words and as either completely voiced regressive assimilation or, unexpectedly, as completely voiceless progressive assimilation in higher-frequency words. Frequency did not predict the voice classifications over and above important acoustic cues to voicing, suggesting that the frequency effects on the classifications were carried exclusively by the acoustic signal. The duration of the cluster and the period of glottal vibration during the cluster decreased while the duration of the release noises increased with frequency. This indicates that speakers reduce articulatory effort for higher-frequency words, with some acoustic cues signaling more voicing and others less voicing. A higher frequency leads not only to acoustic reduction but also to more assimilation.

Abstract

Attention deficit/hyperactivity disorder (ADHD) is a common heritable disorder with a childhood onset. Molecular genetic studies of ADHD have previously focused on examining the roles of specific candidate genes, primarily those involved in dopaminergic pathways. We have performed the first systematic genomewide linkage scan for loci influencing ADHD in 126 affected sib pairs, using a ∼10-cM grid of microsatellite markers. Allele-sharing linkage methods enabled us to exclude any loci with a λs of ⩾3 from 96% of the genome and those with a λs of ⩾2.5 from 91%, indicating that there is unlikely to be a major gene involved in ADHD susceptibility in our sample. Under a strict diagnostic scheme we could exclude all screened regions of the X chromosome for a locus-specific λs of ⩾2 in brother-brother pairs, demonstrating that the excess of affected males with ADHD is probably not attributable to a major X-linked effect. Qualitative trait maximum LOD score analyses pointed to a number of chromosomal sites that may contain genetic risk factors of moderate effect. None exceeded genomewide significance thresholds, but LOD scores were >1.5 for regions on 5p12, 10q26, 12q23, and 16p13. Quantitative-trait analysis of ADHD symptom counts implicated a region on 12p13 (maximum LOD 2.6) that also yielded a LOD >1 when qualitative methods were used. A survey of regions containing 36 genes that have been proposed as candidates for ADHD indicated that 29 of these genes, including DRD4 and DAT1, could be excluded for a λs of 2. Only three of the candidates—DRD5, 5HTT, and CALCYON—coincided with sites of positive linkage identified by our screen. Two of the regions highlighted in the present study, 2q24 and 16p13, coincided with the top linkage peaks reported by a recent genome-scan study of autistic sib pairs.

Abstract

Developmental dyslexia, a specific impairment of reading ability despite adequate intelligence and educational opportunity, is one of the most frequent childhood disorders. Since the first documented cases at the beginning of the last century, it has become increasingly apparent that the reading problems of people with dyslexia form part of a heritable neurobiological syndrome. As for most cognitive and behavioural traits, phenotypic definition is fraught with difficulties and the genetic basis is complex, making the isolation of genetic risk factors a formidable challenge. Against such a background, it is notable that several recent studies have reported the localization of genes that influence dyslexia and other language-related traits. These investigations exploit novel research approaches that are relevant to many areas of human neurogenetics.

Abstract

Studies of dyslexia provide vital insights into the cognitive architecture underpinning both disordered and normal reading. It is well established that inherited factors contribute to dyslexia susceptibility, but only very recently has evidence emerged to implicate specific candidate genes. In this article, we provide an accessible overview of four prominent examples--DYX1C1, KIAA0319, DCDC2 and ROBO1--and discuss their relevance for cognition. In each case correlations have been found between genetic variation and reading impairments, but precise risk variants remain elusive. Although none of these genes is specific to reading-related neuronal circuits, or even to the human brain, they have intriguing roles in neuronal migration or connectivity. Dissection of cognitive mechanisms that subserve reading will ultimately depend on an integrated approach, uniting data from genetic investigations, behavioural studies and neuroimaging.

Abstract

Developmental dyslexia is defined as a specific and significant impairment in reading ability that cannot be explained by deficits in intelligence, learning opportunity, motivation or sensory acuity. It is one of the most frequently diagnosed disorders in childhood, representing a major educational and social problem. It is well established that dyslexia is a significantly heritable trait with a neurobiological basis. The etiological mechanisms remain elusive, however, despite being the focus of intensive multidisciplinary research. All attempts to map quantitative-trait loci (QTLs) influencing dyslexia susceptibility have targeted specific chromosomal regions, so that inferences regarding genetic etiology have been made on the basis of very limited information. Here we present the first two complete QTL-based genome-wide scans for this trait, in large samples of families from the United Kingdom and United States. Using single-point analysis, linkage to marker D18S53 was independently identified as being one of the most significant results of the genome in each scan (P< or =0.0004 for single word-reading ability in each family sample). Multipoint analysis gave increased evidence of 18p11.2 linkage for single-word reading, yielding top empirical P values of 0.00001 (UK) and 0.0004 (US). Measures related to phonological and orthographic processing also showed linkage at this locus. We replicated linkage to 18p11.2 in a third independent sample of families (from the UK), in which the strongest evidence came from a phoneme-awareness measure (most significant P value=0.00004). A combined analysis of all UK families confirmed that this newly discovered 18p QTL is probably a general risk factor for dyslexia, influencing several reading-related processes. This is the first report of QTL-based genome-wide scanning for a human cognitive trait.

Abstract

The mysterious human propensity for acquiring speech and language has fascinated scientists for decades. A substantial body of evidence suggests that this capacity is rooted in aspects of neurodevelopment that are specified at the genomic level. Researchers have begun to identify genetic factors that increase susceptibility to developmental disorders of speech and language, thereby offering the first molecular entry points into neuronal mechanisms underlying human vocal communication. The identification of genetic variants influencing language acquisition facilitates the analysis of animal models in which the corresponding orthologs are disrupted. At face value, the situation raises aperplexing question: if speech and language are uniquely human, can any relevant insights be gained from investigations of gene function in other species? This chapter addresses the question using the example of FOXP2, a gene implicated in a severe monogenic speech and language disorder. FOXP2 encodes a transcription factor that is highly conserved in vertebrate species, both in terms of protein sequence and expression patterns. Current data suggest that an earlier version of this gene, present in the common ancestor of humans, rodents, and birds, was already involved in establishing neuronal circuits underlying sensory-motor integration and learning of complex motor sequences. This may have represented one of the factors providing a permissive neural environment for subsequent evolution of vocal learning. Thus, dissection of neuromolecular pathways regulated by Foxp2 in nonlinguistic species is a necessary prerequisite for understanding the role of the human version of the gene in speech and language.

Abstract

Between 2 and 5% of children who are otherwise unimpaired have significant difficulties in acquiring expressive and/or receptive language, despite adequate intelligence and opportunity. While twin studies indicate a significant role for genetic factors in developmental disorders of speech and language, the majority of families segregating such disorders show complex patterns of inheritance, and are thus not amenable for conventional linkage analysis. A rare exception is the KE family, a large three-generation pedigree in which approximately half of the members are affected with a severe speech and language disorder which appears to be transmitted as an autosomal dominant monogenic trait. This family has been widely publicised as suffering primarily from a defect in the use of grammatical suffixation rules, thus supposedly supporting the existence of genes specific to grammar. The phenotype, however, is broader in nature, with virtually every aspect of grammar and of language affected. In addition, affected members have a severe orofacial dyspraxia, and their speech is largely incomprehensible to the naive listener. We initiated a genome-wide search for linkage in the KE family and have identified a region on chromosome 7 which co-segregates with the speech and language disorder (maximum lod score = 6.62 at theta = 0.0), confirming autosomal dominant inheritance with full penetrance. Further analysis of microsatellites from within the region enabled us to fine map the locus responsible (designated SPCH1) to a 5.6-cM interval in 7q31, thus providing an important step towards its identification. Isolation of SPCH1 may offer the first insight into the molecular genetics of the developmental process that culminates in speech and language.

Abstract

This chapter highlights the research in isolating genetic factors underlying specific language impairment (SLI), or developmental dysphasia, which exploits newly developed genotyping technology, novel statistical methodology, and DNA sequence data generated by the Human Genome Project. The author begins with an overview of results from family, twin, and adoption studies supporting genetic involvement and then goes on to outline progress in a number of genetic mapping efforts that have been recently completed or are currently under way. It has been possible for genetic researchers to pinpoint the specific mutation responsible for some speech and language disorders, providing an example of how the availability of human genomic sequence data can greatly accelerate the pace of disease gene discovery. Finally, the author discusses future prospects on how molecular genetics may offer new insight into the etiology underlying speech and language disorders, leading to improvements in diagnosis and treatment.

Abstract

The rise of molecular genetics is having a pervasive influence in a wide variety of fields, including research into neurodevelopmental disorders like dyslexia, speech and language impairments, and autism. There are many studies underway which are attempting to determine the roles of genetic factors in the aetiology of these disorders. Beyond the obvious implications for diagnosis, treatment and understanding, success in these efforts promises to shed light on the links between genes and aspects of cognition and behaviour. However, the deceptive simplicity of finding correlations between genetic and phenotypic variation has led to a common misconception that there exist straightforward linear relationships between specific genes and particular behavioural and/or cognitive outputs. The problem is exacerbated by the adoption of an abstract view of the nature of the gene, without consideration of molecular, developmental or ontogenetic frameworks. To illustrate the limitations of this perspective, I select two cases from recent research into the genetic underpinnings of neurodevelopmental disorders. First, I discuss the proposal that dyslexia can be dissected into distinct components specified by different genes. Second, I review the story of the FOXP2 gene and its role in human speech and language. In both cases, adoption of an abstract concept of the gene can lead to erroneous conclusions, which are incompatible with current knowledge of molecular and developmental systems. Genes do not specify behaviours or cognitive processes; they make regulatory factors, signalling molecules, receptors, enzymes, and so on, that interact in highly complex networks, modulated by environmental influences, in order to build and maintain the brain. I propose that it is necessary for us to fully embrace the complexity of biological systems, if we are ever to untangle the webs that link genes to cognition.

Abstract

The human capacity to acquire complex language seems to be without parallel in the natural world. The origins of this remarkable trait have long resisted adequate explanation, but advances in fields that range from molecular genetics to cognitive neuroscience offer new promise. Here we synthesize recent developments in linguistics, psychology and neuroimaging with progress in comparative genomics, gene-expression profiling and studies of developmental disorders. We argue that language should be viewed not as a wholesale innovation, but as a complex reconfiguration of ancestral systems that have been adapted in evolutionarily novel ways.

Abstract

This paper examines code and style shifting during sales transactions based on two market case studies from highland Ecuador. Bringing together ideas of linguistic economy with work on stylistic variation and ethnohistorical research on Andean markets, I study bartering, market calls and sales pitches to show how sellers create stylistic performances distinguished by contrasts of code, register and poetic features. The interaction of the symbolic value of language with the economic values of the market presents a place to examine the relationship between discourse and the material world.

Abstract

The human brain supports acquisition mechanisms that extract structural regularities implicitly from experience without the induction of an explicit model. It has been argued that the capacity to generalize to new input is based on the acquisition of abstract representations, which reflect underlying structural regularities in the input ensemble. In this study, we explored the outcome of this acquisition mechanism, and to this end, we investigated the neural correlates of artificial syntactic classification using event-related functional magnetic resonance imaging. The participants engaged once a day during an 8-day period in a short-term memory acquisition task in which consonant-strings generated from an artificial grammar were presented in a sequential fashion without performance feedback. They performed reliably above chance on the grammaticality classification tasks on days 1 and 8 which correlated with a corticostriatal processing network, including frontal, cingulate, inferior parietal, and middle occipital/occipitotemporal regions as well as the caudate nucleus. Part of the left inferior frontal region (BA 45) was specifically related to syntactic violations and showed no sensitivity to local substring familiarity. In addition, the head of the caudate nucleus correlated positively with syntactic correctness on day 8 but not day 1, suggesting that this region contributes to an increase in cognitive processing fluency.

Abstract

Turn on your affective system by tweaking your face muscles - or getting an eyeful of someone else doing the same.

Abstract

Find the fire that's cooking your memory systems.

Abstract

Emotions are powerful on the inside but often displayed in subtle ways on the outside. Are these displays culturally dependent or universal?

Abstract

Genomewide quantitative-trait locus (QTL) linkage analysis was performed using a continuous measure of relative hand skill (PegQ) in a sample of 195 reading-disabled sibling pairs from the United Kingdom. This was the first genomewide screen for any measure related to handedness. The mean PegQ in the sample was equivalent to that of normative data, and PegQ was not correlated with tests of reading ability (correlations between −0.13 and 0.05). Relative hand skill could therefore be considered normal within the sample. A QTL on chromosome 2p11.2-12 yielded strong evidence for linkage to PegQ (empirical P=.00007), and another suggestive QTL on 17p11-q23 was also identified (empirical P=.002). The 2p11.2-12 locus was further analyzed in an independent sample of 143 reading-disabled sibling pairs, and this analysis yielded an empirical P=.13. Relative hand skill therefore is probably a complex multifactorial phenotype with a heterogeneous background, but nevertheless is amenable to QTL-based gene-mapping approaches.

Abstract

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

Abstract

Several quantitative trait loci (QTLs) that influence developmental dyslexia (reading disability [RD]) have been mapped to chromosome regions by linkage analysis. The most consistently replicated area of linkage is on chromosome 6p23-21.3. We used association analysis in 223 siblings from the United Kingdom to identify an underlying QTL on 6p22.2. Our association study implicates a 77-kb region spanning the gene TTRAP and the first four exons of the neighboring uncharacterized gene KIAA0319. The region of association is also directly upstream of a third gene, THEM2. We found evidence of these associations in a second sample of siblings from the United Kingdom, as well as in an independent sample of twin-based sibships from Colorado. One main RD risk haplotype that has a frequency of ∼12% was found in both the U.K. and U.S. samples. The haplotype is not distinguished by any protein-coding polymorphisms, and, therefore, the functional variation may relate to gene expression. The QTL influences a broad range of reading-related cognitive abilities but has no significant impact on general cognitive performance in these samples. In addition, the QTL effect may be largely limited to the severe range of reading disability.

Abstract

A locus on chromosome 2p12-16 has been implicated in dyslexia susceptibility by two independent linkage studies, including our own study of 119 nuclear twin-based families, each with at least one reading-disabled child. Nonetheless, no variant of any gene has been reported to show association with dyslexia, and no consistent clinical evidence exists to identify candidate genes with any strong a priori logic. We used 21 microsatellite markers spanning 2p12-16 to refine our 1-LOD unit linkage support interval to 12cM between D2S337 and D2S286. Then, in quantitative association analysis, two microsatellites yielded P values<0.05 across a range of reading-related measures (D2S2378 and D2S2114). The exon/intron borders of two positional candidate genes within the region were characterized, and the exons were screened for polymorphisms. The genes were Semaphorin4F (SEMA4F), which encodes a protein involved in axonal growth cone guidance, and OTX1, encoding a homeodomain transcription factor involved in forebrain development. Two non-synonymous single nucleotide polymorphisms were found in SEMA4F, each with a heterozygosity of 0.03. One intronic single nucleotide polymorphism between exons 12 and 13 of SEMA4F was tested for quantitative association, but no significant association was found. Only one single nucleotide polymorphism was found in OTX1, which was exonic but silent. Our data therefore suggest that linkage with reading disability at 2p12-16 is not caused by coding variants of SEMA4F or OTX1. Our study outlines the approach necessary for the identification of genetic variants causing dyslexia susceptibility in an epidemiological population of dyslexics.

Abstract

Dyslexia, a disorder of reading and spelling, is a heterogeneous neurological syndrome with a complex genetic and environmental aetiology. People with dyslexia differ in their individual profiles across a range of cognitive, physiological, and behavioural measures related to reading disability. Some or all of the subtypes of dyslexia might have partly or wholly distinct genetic causes. An understanding of the role of genetics in dyslexia could help to diagnose and treat susceptible children more effectively and rapidly than is currently possible and in ways that account for their individual disabilities. This knowledge will also give new insights into the neurobiology of reading and language cognition. Genetic linkage analysis has identified regions of the genome that might harbour inherited variants that cause reading disability. In particular, loci on chromosomes 6 and 18 have shown strong and replicable effects on reading abilities. These genomic regions contain tens or hundreds of candidate genes, and studies aimed at the identification of the specific causal genetic variants are underway.

Abstract

Theeffects of spatial filtering in functional magnetic resonance imaging were investigated by reevaluating the data of a previous study of episodic memory encoding at 2 × 2 × 4-mm3 resolution with use of a SPM99 analysis involving a Gaussian kernel of 8-mm full width at half maximum. In addition, a multisubject analysis of activated regions was performed by normalizing the functional images to an approximate Talairach brain atlas. In individual subjects, spatial filtering merged activations in anatomically separated brain regions. Moreover, small foci of activated pixels which originated from veins became blurred and hence indistinguishable from parenchymal responses. The multisubject analysis resulted in activation of the hippocampus proper, a finding which could not be confirmed by the activation maps obtained at high resolution. It is concluded that the validity of multisubject fMRI analyses can be considerably improved by first analyzing individual data sets at optimum resolution to assess the effects of spatial filtering and minimize the risk of signal contamination by macroscopically visible vessels.

Abstract

Segmentation (and, indeed, definition) of the human body in Kuuk Thaayorre (a Paman language of Cape York Peninsula, Australia) is in some respects typologically unusual, while at other times it conforms to cross-linguistic patterns. The process of deriving complex body part terms from monolexemic items is revealing of metaphorical associations between parts of the body. Associations between parts of the body and entities and phenomena in the broader environment are evidenced by the ubiquity of body part terms (in their extended uses) throughout Thaayorre speech. Understanding the categorisation of the body is therefore prerequisite to understanding the Thaayorre language and worldview.

Abstract

The Error-Related Negativity (ERN) is a component of the event-related brain potential (ERP) that is associated with action monitoring and error detection. The present study addressed the question whether or not an ERN occurs after verbal error detection, e.g., during phoneme monitoring.We obtained an ERN following verbal errors which showed a typical decrease in amplitude under severe time pressure. This result demonstrates that the functioning of the verbal self-monitoring system is comparable to other performance monitoring, such as action monitoring. Furthermore, we found that participants made more errors in phoneme monitoring under time pressure than in a control condition. This may suggest that time pressure decreases the amount of resources available to a capacity-limited self-monitor thereby leading to more errors.

Abstract

The aim of this paper is to explore whether indexing terms for an audiovisual program can be derived from contextual texts automatically. For this we apply natural-language processing techniques to contextual texts of two Dutch TV-programs. We use a Dutch domain thesaurus to derive possible metadata. This possible metadata is ranked by an algorithm which uses the relations of the thesaurus. We evaluate the results by comparing them to human made descriptions.

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 impairs the immediate serial recall of visually presented material. Previously, we have shown that the irrelevant speech effect (ISE) was associated with a relative decrease of regional blood flow in cortical regions subserving the verbal working memory, in particular the superior temporal cortex. In this extension of the previous study, the working memory load was increased and an increased activity as a response to irrelevant speech was noted in the dorsolateral prefrontal cortex. We suggest that the two studies together provide some basic insights as to the nature of the irrelevant speech effect. Firstly, no area in the brain can be ascribed as the single locus of the irrelevant speech effect. Instead, the functional neuroanatomical substrate to the effect can be characterized in terms of changes in networks of functionally interrelated areas. Secondly, the areas that are sensitive to the irrelevant speech effect are also generically activated by the verbal working memory task itself. Finally, the impact of irrelevant speech and related brain activity depends on working memory load as indicated by the differences between the present and the previous study. From a brain perspective, the irrelevant speech effect may represent a complex phenomenon that is a composite of several underlying mechanisms, which depending on the working memory load, include top-down inhibition as well as recruitment of compensatory support and control processes. We suggest that, in the low-load condition, a selection process by an inhibitory top-down modulation is sufficient, whereas in the high-load condition, at or above working memory span, auxiliary adaptive cognitive resources are recruited as compensation

Abstract

Semantic verbal fluency tasks are commonly used in neuropsychological assessment. Investigations of the influence of level of literacy have not yielded consistent results in the literature. This prompted us to investigate the ecological relevance of task specifics, in particular, the choice of semantic criteria used. Two groups of literate and illiterate subjects were compared on two verbal fluency tasks using different semantic criteria. The performance on a food criterion (supermarket fluency task), considered more ecologically relevant for the two literacy groups, and an animal criterion (animal fluency task) were compared. The data were analysed using both quantitative and qualitative measures. The quantitative analysis indicated that the two literacy groups performed equally well on the supermarket fluency task. In contrast, results differed significantly during the animal fluency task. The qualitative analyses indicated differences between groups related to the strategies used, especially with respect to the animal fluency task. The overall results suggest that there is not a substantial difference between literate and illiterate subjects related to the fundamental workings of semantic memory. However, there is indication that the content of semantic memory reflects differences in shared cultural background - in other words, formal education –, as indicated by the significant interaction between level of literacy and semantic criterion.

Abstract

Acquiring the sounds of a language involves learning to recognize distributional patterns present in the input. We show that among adult learners, this distributional learning of auditory categories (which are conceived of here as probability density functions in a multidimensional space) is constrained by the salience of the dimensions that form the axes of this perceptual space. Only with a particular ratio of variation in the perceptual dimensions was category learning driven by the distributional properties of the input.

Abstract

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

Abstract

The discussion on root infinitives has mainly centered around their supposed modal usage. This article aims at modelling the form-function relation of the root infinitive phenomenon by taking into account the full range of interpretational facets encountered cross-linguistically and interindividually. Following the idea of a subsequent ‘‘cell partitioning’’ in the emergence of form-function correlations, I claim that it is the major fission between [+-finite] which is central to express temporal reference different from the default here&now in tense-oriented languages. In aspectual-oriented languages, a similar opposition is mastered with the marking of early aspectual forms. It is observed that in tense-oriented languages like Dutch and German, the progression of functions associated with the infinitival form proceeds from nonmodal to modal, whereas the reverse progression holds for the Russian infinitive. Based on this crucial observation, a model of acquisition is proposed which allows for a flexible and systematic relationship between morphological forms and their respective interpretational biases dependent on their developmental context. As for early child language, I argue that children entertain only two temporal parameters: one parameter is fixed to the here&now point in time, and a second parameter relates to the time talked about, the topic time; this latter time overlaps the situation time as long as no empirical evidence exists to support the emergence of a proper distinction between tense and aspect.

Abstract

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

Abstract

The central topic of this study is to investigate three- and four-place predicate in Yaqui, which are characterized by having multiple object arguments. As with other Southern Uto-Aztecan languages, it has been said that Yaqui follows the Primary/Secondary Object pattern (Dryer 1986). Actually, Yaqui presents three patterns: verbs like nenka ‘sell’ follow the direct–indirect object pattern, verbs like miika ‘give’ follow the primary object pattern, and verbs like chijakta ‘sprinkle’ follow the locative alternation pattern; the primary object pattern is the exclusive one found with derived verbs. This paper shows that the contrast between direct object and primary object languages is not absolute but rather one of degree, and hence two “object” selection principles are needed to explain this mixed system. The two principles are not limited to Yaqui but are found in other languages as well, including English.

Abstract

Trumai, a genetically isolated language spoken in Brazil (Xingu reserve), is an example of an endangered language. Although the Trumai population consists of more than 100 individuals, only 51 people speak the language. The oral traditions are progressively dying. Given the current scenario, the documentation of this language and its cultural aspects is of great importance. In the framework of the DoBeS program (Documentation of Endangered Languages), the project "Documentation of Trumai" has selected and organized a collection of Trumai texts, with a multi-media representation of the corpus. Several kinds of information and data types are being included in the archive of the language: texts with audio and video recordings; written texts from educational materials; drawings; photos; songs; annotations in different formats; lexicon; field notes; results from scientific studies of the language (sound system, sketch grammar, comparative studies with other Xinguan languages), etc. All materials are integrated into the IMDI-Browser, a specialized tool for presenting and searching for linguistic data. This paper explores the processing phases and the results of the Trumai project taking into consideration the issue of how to combine the needs and wishes of field linguistics (content and research aspects) and the needs of archiving (structure and workflow aspects) in a well-organized corpus.

Abstract

This paper outlines some reasons for why gestures are relevant to the study of SLA. First, given cross-cultural and cross-linguistic gestural repertoires, gestures can be treated as part of what learners can acquire in a target language. Gestures can therefore be studied as a developing system in their own right both in L2 production and comprehension. Second, because of the close link between gestures, language, and speech, learners' gestures as deployed in L2 usage and interaction can offer valuable insights into the processes of acquisition, such as the handling of expressive difficulties, the influence of the first language, interlanguage phenomena, and possibly even into planning and processing difficulties. As a form of input to learners and to their interlocutors alike, finally, gestures also play a potential role for comprehension and learning.

Abstract

The papers in this volume explore the cognitive neuroscience of second language acquisition from the perspectives of critical/sensitive periods, maturational effects, individual differences, neural regions involved, and processing characteristics. The research methodologies used include functional magnetic resonance imaging (fMRI), positron emission tomography (PET), and event related potentials (ERP). Questions addressed include: Which brain areas are reliably activated in second language processing? Are they the same or different from those activated in first language acquisition and use? What are the behavioral consequences of individual differences among brains? What are the consequences of anatomical and physiological differences, learner proficiency effects, critical/sensitive periods? What role does degeneracy, in which two different neural systems can produce the same behavioral output, play? What does it mean that learners' brains respond to linguistic distinctions that cannot be recognized or produced yet? The studies in this volume provide initial answers to all of these questions.

Abstract

This study investigates whether addressees visually attend to speakers’ gestures in interaction and whether attention is modulated by changes in social setting and display size. We compare a live face-to-face setting to two video conditions. In all conditions, the face dominates as a fixation target and only a minority of gestures draw fixations. The social and size parameters affect gaze mainly when combined and in the opposite direction from the predicted with fewer gestures fixated on video than live. Gestural holds and speakers’ gaze at their own gestures reliably attract addressees’ fixations in all conditions. The attraction force of holds is unaffected by changes in social and size parameters, suggesting a bottom-up response, whereas speaker-fixated gestures draw significantly less attention in both video conditions, suggesting a social effect for overt gaze-following and visual joint attention. The study provides and validates a video-based paradigm enabling further experimental but ecologically valid explorations of cross-modal information processing.

Abstract

The production of cohesive discourse, especially maintained reference, poses problems for early second language (L2) speakers. This paper considers a communicative account of overexplicit L2 discourse by focusing on the interdependence between spoken and gestural cohesion, the latter being expressed by anchoring of referents in gesture space. Specifically, this study investigates whether overexplicit maintained reference in speech (lexical noun phrases [NPs]) and gesture (anaphoric gestures) constitutes an interactional communication strategy. We examine L2 speech and gestures of 16 Dutch learners of French retelling stories to addressees under two visibility conditions. The results indicate that the overexplicit properties of L2 speech are not motivated by interactional strategic concerns. The results for anaphoric gestures are more complex. Although their presence is not interactionally

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

A prototypical lexicon tool was implemented which was intended to allow researchers to collaboratively create lexicons of endangered languages. Increasingly often researchers documenting or analyzing a language work at different locations. Lexicons that evolve through continuous interaction between the collaborators can only be efficiently produced when it can be accessed and manipulated via the Internet. The SHAWEL tool was developed to address these needs; it makes use of a thin Java client and a central database solution.

Abstract

Three groups of monolingual listeners, with Standard Chinese, Dutch and Hungarian as their native language, judged pairs of trisyllabic stimuli which differed only in their itch pattern. The segmental structure of the stimuli was made up by the experimenters and presented to subjects as being taken from a little-known language spoken on a South Pacific island. Pitch patterns consisted of a single rise-fall located on or near the second syllable. By and large, listeners selected the stimulus with the higher peak, the later eak, and the higher end rise as the one that signalled a question, regardless of language group. The result is argued to reflect innate, non-linguistic knowledge of the meaning of pitch variation, notably Ohala’s Frequency Code. A significant difference between groups is explained as due to the influence of the mother tongue.

Abstract

Rede uitgesproken op 12 mei 2000 bij de aanvaarding van het ambt van hoogleraar in de neuropsychologie aan de Faculteit Sociale Wetenschappen KUN.

Abstract

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

Abstract

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

Abstract

Although the sentences that we hear or read have meaning, this does not necessarily mean that they are also true. Relatively little is known about the critical brain structures for, and the relative time course of, establishing the meaning and truth of linguistic expressions. We present electroencephalogram data that show the rapid parallel integration of both semantic and world
knowledge during the interpretation of a sentence. Data from functional magnetic resonance imaging revealed that the left inferior prefrontal cortex is involved in the integration of both meaning and world knowledge. Finally, oscillatory brain responses indicate that the brain keeps a record of what makes a sentence hard to interpret.

Abstract

We explore the nature of the oscillatory dynamics in the EEG of subjects reading sentences that contain a semantic violation. More specifically, we examine whether increases in theta (≈3–7 Hz) and gamma (around 40 Hz) band power occur in response to sentences that were either semantically correct or contained a semantically incongruent word (semantic violation). ERP results indicated a classical N400 effect. A wavelet-based time-frequency analysis revealed a theta band power increase during an interval of 300–800 ms after critical word onset, at temporal electrodes bilaterally for both sentence conditions, and over midfrontal areas for the semantic violations only. In the gamma frequency band, a predominantly frontal power increase was observed during the processing of correct sentences. This effect was absent following semantic violations. These results provide a characterization of the oscillatory brain dynamics, and notably of both theta and gamma oscillations, that occur during language comprehension.

Abstract

This paper investigates the time and space complexity of word order computation in the psycholinguistically motivated grammar formalism of Performance Grammar (PG). In PG, the first stage of syntax assembly yields an unordered tree ('mobile') consisting of a hierarchy of lexical frames (lexically anchored elementary trees). Associated with each lexica l frame is a linearizer—a Finite-State Automaton that locally computes the left-to-right order of the branches of the frame. Linearization takes place after the promotion component may have raised certain constituents (e.g. Wh- or focused phrases) into the domain of lexical frames higher up in the syntactic mobile. We show that the worst-case time and space complexity of analyzing input strings of length n is O(n5) and O(n4), respectively. This result compares favorably with the time complexity of word-order computations in Tree Adjoining Grammar (TAG). A comparison with Head-Driven Phrase Structure Grammar (HPSG) reveals that PG yields a more declarative linearization method, provided that the FSA is rewritten as an equivalent regular expression.

Abstract

Many current sentence generators lack the ability to compute elliptical versions of coordinated clauses in accordance with the rules for Gapping, Forward and Backward Conjunction Reduction, and SGF (Subject Gap in clauses with Finite/ Fronted verb). We describe a module (implemented in JAVA, with German and Dutch as target languages) that takes non-elliptical coordinated clauses as input and returns all reduced versions licensed by coordinative ellipsis. It is loosely based on a new psycholinguistic theory of coordinative ellipsis proposed by Kempen. In this theory, coordinative ellipsis is not supposed to result from the application of declarative grammar rules for clause formation but from a procedural component that interacts with the sentence generator and may block the overt expression of certain constituents.

Abstract

We describe a generation-oriented workbench for the Performance Grammar (PG) formalism, highlighting the treatment of certain word order and movement constraints in Dutch and German. PG enables a simple and uniform treatment of a heterogeneous collection of linear order phenomena in the domain of verb constructions (variably known as Cross-serial Dependencies, Verb Raising, Clause Union, Extraposition, Third Construction, Particle Hopping, etc.). The central data structures enabling this feature are clausal “topologies”: one-dimensional arrays associated with clauses, whose cells (“slots”) provide landing sites for the constituents of the clause. Movement operations are enabled by unification of lateral slots of topologies at adjacent levels of the clause hierarchy. The PGW generator assists the grammar developer in testing whether the implemented syntactic knowledge allows all and only the well-formed permutations of constituents.

Abstract

We present a quantitative model of word order and movement constraints that enables a simple and uniform treatment of a seemingly heterogeneous collection of linear order phenomena in English, Dutch and German complement constructions (Wh-extraction, clause union, extraposition, verb clustering, particle movement, etc.). Underlying the scheme are central assumptions of the psycholinguistically motivated Performance Grammar (PG). Here we describe this formalism in declarative terms based on typed feature unification. PG allows a homogenous treatment of both the within- and between-language variations of the ordering phenomena under discussion, which reduce to different settings of a small number of quantitative parameters.

Abstract

Drawings of objects were presented in series of 54 each to 14 German speaking subjects with the tasks to indicate by button presses a) whether the grammatical gender of an object name was masculine ("der") or feminine ("die") and b) whether the depicted object was man-made or nature-made. The magnetoencephalogram (MEG) was recorded with a whole-head neuromagnetometer and task-specific patterns of brain activity were determined in the source space (Minimum Norm Estimates, MNE). A left-temporal focus of activity 150-275 ms after stimulus onset in the gender decision compared to the semantic classification task was discussed as indicating the retrieval of syntactic information, while a more expanded left hemispheric activity in the gender relative to the semantic task 300-625 ms after stimulus onset was discussed as indicating phonological encoding. A predominance of activity in the semantic task was observed over right fronto-central region 150-225 ms after stimulus-onset, suggesting that semantic and syntactic processes are prominent in this stage of lexical selection.

Abstract

Comparatively little is known about the inherited primate background underlying human cognition, the human cognitive “wild-type.” Yet it is possible to trace the evolution of human cognitive abilities and tendencies by contrasting the skills of our nearest cousins, not just chimpanzees, but all the extant great apes, thus showing what we are likely to have inherited from the common ancestor [1]. By looking at human infants early in cognitive development, we can also obtain insights into native cognitive biases in our species [2]. Here, we focus on spatial memory, a central cognitive domain. We show, first, that all nonhuman great apes and 1-year-old human infants exhibit a preference for place over feature strategies for spatial memory. This suggests the common ancestor of all great apes had the same preference. We then examine 3-year-old human children and find that this preference reverses. Thus, the continuity between our species and the other great apes is masked early in human ontogeny. These findings, based on both phylogenetic and ontogenetic contrasts, open up the prospect of a systematic evolutionary psychology resting upon the cladistics of cognitive preferences.

Abstract

Current approaches to human cognition often take a strong nativist stance based on Western adult performance, backed up where possible by neonate and infant research and almost never by comparative research across the Hominidae. Recent research suggests considerable cross-cultural differences in cognitive strategies, including relational thinking, a domain where infant research is impossible because of lack of cognitive maturation. Here, we apply the same paradigm across children and adults of different cultures and across all nonhuman great ape genera. We find that both child and adult spatial cognition systematically varies with language and culture but that, nevertheless, there is a clear inherited bias for one spatial strategy in the great apes. It is reasonable to conclude, we argue, that language and culture mask the native tendencies in our species. This cladistic approach suggests that the correct perspective on human cognition is neither nativist uniformitarian nor ‘‘blank slate’’ but recognizes the powerful impact that language and culture can have on our shared primate cognitive biases.

Abstract

We advance the hypothesis here that the higher-than-average vocal pitch (FO) found for speech of Broca's aphasics in experimental settings is due, in part, to increased psychological stress. Two experiments were conducted which manipulated conversational constraints and the sentence forms to be produced by aphasic patients. Our study revealed significant differences between changes in vocal pitch of agrammatic Broca's aphasics versus those of Wernicke's aphasics and normal controls. It is suggested that the greater psychological stress experienced by the Broca's aphasics, but not by the Wernicke's aphasics, accounts for these observed differences.

Abstract

Interrogative structures such as ‘Could you pass the salt? and ‘Couldn’t you pass the salt?’ can be used for making requests. A study of such pairs within a conversation analytic framework suggests that these are not used interchangeably, and that they have different impacts on the interaction. Focusing on Danish interactions between elderly care recipients and their home help assistants, I demonstrate how the care recipient displays different degrees of stance towards whether she is entitled to make a request or not, depending on whether she formats her request as a positive or a negative interrogative. With a positive interrogative request, the care recipient orients to her request as one she is not entitled to make. This is underscored by other features, such as the use of mitigating devices and the choice of verb. When accounting for this type of request, the care recipient ties the request to the specific situation she is in, at the moment in which the request is produced. In turn, the home help assistant orients to the lack of entitlement by resisting the request. With a negative interrogative request, the care recipient, in contrast, orients to her request as one she is entitled to make. This is strengthened by the choice of verb and the lack of mitigating devices. When such requests are accounted for, the requested task is treated as something that should be routinely performed, and hence as something the home help assistant has neglected to do. In turn, the home help assistant orients to the display of entitlement by treating the request as unproblematic, and by complying with it immediately.

Abstract

Longitudinally collected VOT data from an early English-Italian bilingual who became increasingly English-dominant was analyzed. Stops in English were always produced with significantly longer VOT than in Italian. However, the speaker did not show any significant change in the VOT production in either language over time, despite the clear dominance of English in his every day language use later in his life. The results indicate that – unlike L2 learners – early bilinguals may remain unaffected by language use with respect to phonetic realization.

Abstract

When a sentence such as The model embraced the designer and the photographer laughed is read, the noun phrase the photographer is temporarily ambiguous: It can be either one of the objects of embraced (NP-coordination) or the subject of a new, conjoined sentence (S-coordination). It has been shown for a number of languages, including Dutch (the language used in this study), that readers prefer NP-coordination over S-coordination, at least in isolated sentences. In the present paper, it will be suggested that NP-coordination is preferred because it is the simpler of the two options in terms of topic-structure; in NP-coordinations there is only one topic, whereas S-coordinations contain two. Results from off-line (sentence completion) and online studies (a self-paced reading and an eye tracking experiment) support this topic-structure explanation. The processing difficulty associated with S-coordinated sentences disappeared when these sentences followed contexts favoring a two-topic continuation. This finding establishes topic-structure as an important factor in online sentence processing.

Abstract

When faced with the noun phrase (NP) versus sentence (S) coordination ambiguity as in, for example, The thief shot the jeweller and the cop hellip, readers prefer the reading with NP-coordination (e.g., "The thief shot the jeweller and the cop yesterday") over one with two conjoined sentences (e.g., "The thief shot the jeweller and the cop panicked"). A corpus study is presented showing that NP-coordinations are produced far more often than S-coordinations, which in frequency-based accounts of parsing might be taken to explain the NP-coordination preference. In addition, we describe an eye-tracking experiment investigating S-coordinated sentences such as Jasper sanded the board and the carpenter laughed, where the poor thematic fit between carpenter and sanded argues against NP-coordination. Our results indicate that information regarding poor thematic fit was used rapidly, but not without leaving some residual processing difficulty. This is compatible with claims that thematic information can reduce but not completely eliminate garden-path effects.