Publications

Abstract

This paper presents results from a new set of experiments using the sentence matching paradigm (Forster, Kenneth (1979), Freedman & Forster (1985), also Bley-Vroman & Masterson (1989), investigating native-speakers’ and L2 learners’ knowledge of constraints on clitic placement in French.1 Our purpose is three-fold: (i) to shed more light on the contrasts between native-speakers and L2 learners observed in previous experiments, especially Duffield & White (1999), and Duffield, White, Bruhn de Garavito, Montrul & Prévost (2002); (ii), to address specific criticisms of the sentence-matching paradigm leveled by Gass (2001); (iii), to provide a firm empirical basis for follow-up experiments with L2 learners

Abstract

Previous studies, including Duffield and Matsuo (2001; 2002; 2009), have demonstrated second language learners’ overall sensitivity to a parallelism constraint governing English VP-ellipsis constructions: like native speakers (NS), advanced Dutch, Spanish and Japanese learners of English reliably prefer ellipsis clauses with structurally parallel antecedents over those with non-parallel antecedents. However, these studies also suggest that, in contrast to English native speakers, L2 learners’ sensitivity to parallelism is strongly influenced by other non-syntactic formal factors, such that the constraint applies in a comparatively restricted range of construction-specific contexts. This article reports a set of follow-up experiments — from both computer-based as well as more traditional acceptability judgement tasks — that systematically manipulates these other factors. Convergent results from these tasks confirm a qualitative difference in the judgement patterns of the two groups, as well as important differences between theoreticians’ judgements and those of typical native speakers. We consider the implications of these findings for theories of ultimate attainment in second language acquisition (SLA), as well as for current theoretical accounts of ellipsis.

Abstract

This paper builds on a previous work in which we attempted to retrieve a phylogenetic signal using abstract structural features alone, as opposed to cognate sets, drawn from a sample of Island Melanesian languages, both Oceanic (Austronesian) and (non-Austronesian) Papuan (Science 2005[309]: 2072-75 ). Here we clarify a number of misunderstandings of this approach, referring particularly to the critique by Mark Donohue and Simon Musgrave (in this same issue of Oceanic Linguistics), in which they fail to appreciate the statistical principles underlying computational phylogenetic methods. We also present new analyses that provide stronger evidence supporting the hypotheses put forward in our original paper: a reanalysis using Bayesian phylogenetic inference demonstrates the robustness of the data and methods, and provides a substantial improvement over the parsimony method used in our earlier paper. We further demonstrate, using the technique of spatial autocorrelation, that neither proximity nor Oceanic contact can be a major determinant of the pattern of structural variation of the Papuan languages, and thus that the phylogenetic relatedness of the Papuan languages remains a serious hypothesis.

Abstract

The Touo language is a non-Austronesian language spoken on Rendova Island (Western Province, Solomon Islands). First language speakers of Touo are typically multilingual, and are likely to speak other (Austronesian) vernaculars, as well as Solomon Island Pijin and English. There is no institutional support of literacy in Touo: schools function in English, and church-based support for vernacular literacy focuses on the major Austronesian languages of the local area. Touo vernacular literacy exists in a restricted niche of the linguistic ecology, where it is utilised for symbolic rather than communicative goals. Competing vernacular orthographic traditions complicate the situation further.

Abstract

This paper shows that despite evidence of structural convergence between some of the Austronesian and non-Austronesian (Papuan) languages of Island Melanesia, statistical methods can detect two independent genealogical signals derived from linguistic structural features. Earlier work by the author and others has presented a maximum parsimony analysis which gave evidence for a genealogical connection between the non-Austronesian languages of island Melanesia. Using the same data set, this paper demonstrates for the non-statistician the application of more sophisticated statistical techniques—including Bayesian methods of phylogenetic inference, and shows that the evidence for common ancestry is if anything stronger than originally supposed.

Abstract

As proposed by Ameka and Levinson (this issue) locative verb systems can be classified into four types according to the number of verbs distinguished. This article addresses the lower extreme of this typology: languages which offer no choice of verb in the basic locative function (BLF). These languages have either a single locative verb, or do not use verbs at all in the basic locative construction (BLC, the construction used to encode the BLF). A close analysis is presented of the behavior of BLF predicate types in four genetically diverse languages: Chukchi (Chukotko-Kamchatkan, Russian Arctic), and Lavukaleve (Papuan isolate, Solomon Islands), which have BLC with the normal copula/existential verb for the language; Tiriyó (Cariban/Taranoan, Brazil), which has an optional copula in the BLC; and Saliba (Austronesian/Western Oceanic, Papua New Guinea), a language with a verbless clause as the BLC. The status of these languages in the typology of positional verb systems is reviewed, and other relevant typological generalizations are discussed

Abstract

Kazukuru is an extinct language, originally spoken in the inland of the western part of the island of New Georgia, Solomon Islands, and attested by very limited historical sources. Kazukuru has generally been considered to be a Papuan, that is, non-Austronesian, language, mostly on the basis of its lexicon. Reevaluation of the available data suggests a high likelihood that Kazukuru was in fact an Oceanic Austronesian language. Pronominal paradigms are clearly of Austronesian origin, and many other aspects of language structured retrievable from the limited data are also congruent with regional Oceanic Austronesian typology. The extent and possible causes of Kazukuru lexical deviations from the Austronesian norm are evaluated and discussed.

Abstract

Genome wide complex trait analysis (GCTA) is extended to include environmental effects of the maternal genotype on offspring phenotype (“maternal effects”, M-GCTA). The model includes parameters for the direct effects of the offspring genotype, maternal effects and the covariance between direct and maternal effects. Analysis of simulated data, conducted in OpenMx, confirmed that model parameters could be recovered by full information maximum likelihood (FIML) and evaluated the biases that arise in conventional GCTA when indirect genetic effects are ignored. Estimates derived from FIML in OpenMx showed very close agreement to those obtained by restricted maximum likelihood using the published algorithm for GCTA. The method was also applied to illustrative perinatal phenotypes from ~4,000 mother-offspring pairs from the Avon Longitudinal Study of Parents and Children. The relative merits of extended GCTA in contrast to quantitative genetic approaches based on analyzing the phenotypic covariance structure of kinships are considered.

Abstract

We investigated the roles of top-down task set and bottom-up stimulus salience for feature-specific attentional capture. ERPs and behavioural performance were measured in two experiments where spatially nonpredictive cues preceded visual search arrays that included a colour-defined target. When cue arrays contained a target-colour singleton, behavioural spatial cueing effects were accompanied by a cue-induced N2pc component, indicative of attentional capture. Behavioural cueing effects and N2pc components were only minimally attenuated for non-singleton relative to singleton target-colour cues, demonstrating that top-down task set has a much greater impact on attentional capture than bottom-up salience. For nontarget-colour singleton cues, no N2pc was triggered, but an anterior N2 component indicative of top-down inhibition was observed. In Experiment 2, these cues produced an inverted behavioural cueing effect, which was accompanied by a delayed N2pc to targets presented at cued locations. These results suggest that perceptually salient visual stimuli without task-relevant features trigger a transient location-specific inhibition process that prevents attentional capture, but delays the selection of subsequent target events.

Abstract

It has been proposed that two amino acid substitutions in the transcription factor FOXP2 have been positively selected during human evolution due to effects on aspects of speech and language. Here, we introduce these substitutions into the endogenous Foxp2 gene of mice. Although these mice are generally healthy, they have qualitatively different ultrasonic vocalizations, decreased exploratory behavior and decreased dopamine concentrations in the brain suggesting that the humanized Foxp2 allele affects basal ganglia. In the striatum, a part of the basal ganglia affected in humans with a speech deficit due to a nonfunctional FOXP2 allele, we find that medium spiny neurons have increased dendrite lengths and increased synaptic plasticity. Since mice carrying one nonfunctional Foxp2 allele show opposite effects, this suggests that alterations in cortico-basal ganglia circuits might have been important for the evolution of speech and language in humans.

Abstract

This article presents a study of a set of pointing gestures produced together with speech in a corpus of video-recorded “locality description” interviews in rural Laos. In a restricted set of the observed gestures (we did not consider gestures with special hand shapes, gestures with arc/tracing motion, or gestures directed at referents within physical reach), two basic formal types of pointing gesture are observed: B-points (large movement, full arm, eye gaze often aligned) and S-points (small movement, hand only, casual articulation). Taking the approach that speech and gesture are structurally integrated in composite utterances, we observe that these types of pointing gesture have distinct pragmatic functions at the utterance level. One type of gesture (usually “big” in form) carries primary, informationally foregrounded information (for saying “where” or “which one”). Infants perform this type of gesture long before they can talk. The second type of gesture (usually “small” in form) carries secondary, informationally backgrounded information which responds to a possible but uncertain lack of referential common ground. We propose that the packaging of the extra locational information into a casual gesture is a way of adding extra information to an utterance without it being on-record that the added information was necessary. This is motivated by the conflict between two general imperatives of communication in social interaction: a social-affiliational imperative not to provide more information than necessary (“Don’t over-tell”), and an informational imperative not to provide less information than necessary (“Don’t under-tell”).

Abstract

Research on video- and audio-recordings of spontaneous naturally-occurring conversation in English has shown that conversation is a rule-guided, practice-oriented domain that can be investigated for its underlying mechanics or structure. Systematic study could yield something like a grammar for conversation. The goal of this task is to acquire a corpus of video-data, for investigating the underlying structure(s) of interaction cross-linguistically and cross-culturally.

Abstract

Any language will have a range of predicates that specify three core participants (e.g. 'put', 'show', 'give'), and will conventionally provide a range of constructional types for the expression of these three participants in a structured single-clause or single-sentence event description. This article examines the clausal encoding of three-participant events in Lao, a Tai language of Southeast Asia. There is no possibility in Lao for expression of three full arguments in the core of a single-verb clause (although it is possible to have a third argument in a noncore slot, marked as oblique with a prepositionlike element). Available alternatives include extraposing an argument using a topic-comment construction, incorporating an argument into the verb phrase, and ellipsing one or more contextually retrievable arguments. A more common strategy is verb serialization, for example, where a threeplace verb (e.g. 'put') is assisted by an additional verb (typically a verb of handling such as 'carry') that provides a slot for the theme argument (e.g. the transferred object in a putting scene). The event construal encoded by this type of structure decomposes the event into a first stage in which the agent comes into control over a theme, and a second in which the agent performs a controlled action (e.g. of transfer) with respect to that theme and a goal (and/or source). The particular set of strategies that Lao offers for encoding three-participant events — notably, topic-comment strategy, ellipsis strategy, serial verb strategy — conform with (and are presumably motivated by) the general typological profile of the language. The typological features of Lao are typical for the mainland Southeast Asia area (isolating, topic-prominent, verb-serializing, widespread nominal ellipsis).

Abstract

While there are infinite conceivable events of material separation, those actually encoded in the conventions of a given language's verb semantics number only a few. Furthermore, there appear to be crosslinguistic parallels in the native verbal analysis of this conceptual domain. What are the operative distinctions, and why these? This article analyses a key subset of the bivalent (transitive) verbs of cutting and breaking in Lao. I present a decompositional analysis of the verbs glossed 'cut (off)', 'cut.into.with.placed.blade', 'cut.into.with.moving.blade', and 'snap', pursuing the idea that the attested combinations of sub-events have a natural logic to them. Consideration of the nature of linguistic categories, as distinct from categories in general, suggests that the attested distinctions must have ethnographic and social interactional significance, raising new lines of research for cognitive semantics.

Abstract

This chapter discusses some of the elements of human sociality that serve as the social and cognitive infrastructure or preconditions for the use of requests and other kinds of recruitments in interaction. The notion of an agent with goals is a canonical starting point, though importantly agency tends not to be wholly located in individuals, but rather is socially distributed. This is well illustrated in the case of requests, in which the person or group that has a certain goal is not necessarily the one who carries out the behavior towards that goal. The chapter focuses on the role of semiotic (mostly linguistic) resources in negotiating the distribution of agency with request-like actions, with examples from video-recorded interaction in Lao, a language spoken in Laos and nearby countries. The examples illustrate five hallmarks of requesting in human interaction, which show some ways in which our ‘manipulation’ of other people is quite unlike our manipulation of tools: (1) that even though B is being manipulated, B wants to help, (2) that while A is manipulating B now, A may be manipulated in return later; (3) that the goal of the behavior may be shared between A and B, (4) that B may not comply, or may comply differently than requested, due to actual or potential contingencies, and (5) that A and B are accountable to one another; reasons may be asked for, and/or given, for the request. These hallmarks of requesting are grounded in a prosocial framework of human agency.

Abstract

People of all cultures have some degree of concern with categorizing types of communicative social action. All languages have words with meanings like speak, say, talk, complain, curse, promise, accuse, nod, wink, point and chant. But the exact distinctions they make will differ in both quantity and quality. How is communicative social action categorised across languages and cultures? The goal of this task is to establish a basis for cross-linguistic comparison of native metalanguages for social action.

Abstract

The approach to pragmatics explored in this article focuses on elements of social interaction which are of universal relevance, and which may provide bases for a comparative approach. The discussion is anchored by reference to a fragment of conversation from a video-recording of Lao speakers during a home visit in rural Laos. The following points are discussed. First, an understanding of the full richness of context is indispensable for a proper understanding of any interaction. Second, human relationships are a primary locus of social organization, and as such constitute a key focus for pragmatics. Third, human social intelligence forms a universal cognitive under-carriage for interaction, and requires careful cross-cultural study. Fourth, a neo-Peircean framework for a general understanding of semiotic processes gives us a way of stepping away from language as our basic analytical frame. It is argued that in order to get a grip on pragmatics across human groups, we need to take a comparative approach in the biological sense—i.e. with reference to other species as well. From this perspective, human pragmatics is about using semiotic resources to try to meet goals in the realm of social relationships.

Abstract

This sub-project is concerned with analysis and cross-linguistic comparison of the mechanisms of signaling and redressing ‘trouble’ during conversation. Speakers and listeners constantly face difficulties with many different aspects of speech production and comprehension during conversation. A speaker may mispronounce a word, or may be unable to find a word, or be unable to formulate in words an idea he or she has in mind. A listener may have troubling hearing (part of) what was said, may not know who a speaker is referring to, may not be sure of the current relevance of what is being said. There may be problems in the organisation of turns at talk, for instance, two speakers’ speech may be in overlap. The goal of this task is to investigate the range of practices that a language uses to address problems of speaking, hearing and understanding in conversation.

Abstract

Human actions in the social world – like greeting, requesting, complaining, accusing, asking, confirming, etc. – are recognised through the interpretation of signs. Language is where much of the action is, but gesture, facial expression and other bodily actions matter as well. The goal of this task is to establish a maximally rich description of a representative, good quality piece of conversational interaction, which will serve as a reference point for comparative exploration of the status of social actions and their formulation across language

Abstract

This article shows that Old-French literary texts differ systematically in their relative frequencies of syntactic constructions. These frequencies reflect differences in register (poetry versus prose), region (Picardy, Champagne, and Esatern France), time period (until 1250, 1251 – 1300, 1301 – 1350), and genre (hagiography, romance of chivalry, or other).

Abstract

Two lexical decision experiments addressed the role of paradigmatic effects in auditory word recognition. Experiment 1 showed that listeners classified a form with an incorrectly voiced final obstruent more readily as a word if the obstruent is realised as voiced in other forms of that word's morphological paradigm. Moreover, if such was the case, the exact probability of paradigmatic voicing emerged as a significant predictor of the response latencies. A greater probability of voicing correlated with longer response latencies for words correctly realised with voiceless final obstruents. A similar effect of this probability was observed in Experiment 2 for words with completely voiceless or weakly voiced (incompletely neutralised) final obstruents. These data demonstrate the relevance of paradigmatically related complex words for the processing of morphologically simple words in auditory word recognition.

Abstract

Acoustic reduction refers to the frequent phenomenon in conversational speech that words are produced with fewer or lenited segments compared to their citation forms. The few published studies on the production and comprehension of acoustic reduction have important implications for the debate on the relevance of abstractions and exemplars in speech processing. This article discusses these implications. It first briefly introduces the key assumptions of simple abstractionist and simple exemplar-based models. It then discusses the literature on acoustic reduction and draws the conclusion that both types of models need to be extended to explain all findings. The ultimate model should allow for the storage of different pronunciation variants, but also reserve an important role for phonetic implementation. Furthermore, the recognition of a highly reduced pronunciation variant requires top down information and leads to activation of the corresponding unreduced variant, the variant that reaches listeners’ consciousness. These findings are best accounted for in hybrids models, assuming both abstract representations and exemplars. None of the hybrid models formulated so far can account for all data on reduced speech and we need further research for obtaining detailed insight into how speakers produce and listeners comprehend reduced speech.

Abstract

In Dutch, all morpheme-final obstruents are voiceless in word-final position. As a consequence, the distinction between obstruents that are voiced before vowel-initial suffixes and those that are always voiceless is neutralized. This study adds to the existing evidence that the neutralization is incomplete: neutralized, alternating plosives tend to have shorter bursts than non-alternating plosives. Furthermore, in a rating study, listeners scored the alternating plosives as more voiced than the nonalternating plosives, showing sensitivity to the subtle subphonemic cues in the acoustic signal. Importantly, the participants who were presented with the complete words, instead of just the final rhymes, scored the alternating plosives as even more voiced. This shows that listeners’ perception of voice is affected by their knowledge of the obstruent’s realization in the word’s morphological paradigm. Apparently, subphonemic paradigmatic levelling is a characteristic of both production and perception. We explain the effects within an analogy-based approach.

Abstract

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

Abstract

Talk of linguistic universals has given cognitive scientists the impression that languages are all built to a common pattern. In fact, there are vanishingly few universals of language in the direct sense that all languages exhibit them. Instead, diversity can be found at almost every level of linguistic organization. This fundamentally changes the object of enquiry from a cognitive science perspective. This target article summarizes decades of cross-linguistic work by typologists and descriptive linguists, showing just how few and unprofound the universal characteristics of language are, once we honestly confront the diversity offered to us by the world's 6,000 to 8,000 languages. After surveying the various uses of “universal,” we illustrate the ways languages vary radically in sound, meaning, and syntactic organization, and then we examine in more detail the core grammatical machinery of recursion, constituency, and grammatical relations. Although there are significant recurrent patterns in organization, these are better explained as stable engineering solutions satisfying multiple design constraints, reflecting both cultural-historical factors and the constraints of human cognition.

Abstract

When we have spoken conversations, it is usually in the context of competing sounds within our environment. Speech can be masked by many different kinds of sounds, for example, machinery noise and the speech of others, and these different sounds place differing demands on cognitive resources. In this talk, I will present data from a series of functional magnetic resonance imaging (fMRI) studies in which the informational properties of background sounds have been manipulated to make them more or less similar to speech. I will demonstrate the neural effects associated with speaking over and listening to these sounds, and demonstrate how in perception these effects are modulated by the age of the listener. The results will be interpreted within a framework of auditory processing developed from primate neurophysiology and human functional imaging work (Rauschecker and Scott 2009).

Abstract

Our response takes advantage of the wide-ranging commentary to clarify some aspects of our original proposal and augment others. We argue against the generative critics of our coevolutionary program for the language sciences, defend the use of close-to-surface models as minimizing crosslinguistic data distortion, and stress the growing role of stochastic simulations in making generalized historical accounts testable. These methods lead the search for general principles away from idealized representations and towards selective processes. Putting cultural evolution central in understanding language diversity makes learning fundamental in the cognition of language: increasingly powerful models of general learning, paired with channelled caregiver input, seem set to manage language acquisition without recourse to any innate “universal grammar.” Understanding why human language has no clear parallels in the animal world requires a cross-species perspective: crucial ingredients are vocal learning (for which there are clear non-primate parallels) and an intentionattributing cognitive infrastructure that provides a universal base for language evolution. We conclude by situating linguistic diversity within a broader trend towards understanding human cognition through the study of variation in, for example, human genetics, neurocognition, and psycholinguistic processing.

Abstract

Daniel Everett has spent his career in the Amazon, challenging some fundamental ideas about language and thought. Asifa Majid and Jon Sutton pose the questions

Abstract

This chapter summarizes the extensive discussions that took place during the Forum as well as the subsequent months thereafter. It assesses current understanding of the neuronal mechanisms that underlie syntactic structure and processing.... It is posited that to understand the neurobiology of syntax, it might be worthwhile to shift the balance from comprehension to syntactic encoding in language production

Abstract

In this study, we investigate whether language and music share cognitive resources for structural processing. We report an experiment that used sung materials and manipulated linguistic complexity (subject-extracted relative clauses, object-extracted relative clauses) and musical complexity (in-key critical note, out-of-key critical note, auditory anomaly on the critical note involving a loudness increase). The auditory-anomaly manipulation was included in order to test whether the difference between in-key and out-of-key conditions might be due to any salient, unexpected acoustic event. The critical dependent measure involved comprehension accuracies to questions about the propositional content of the sentences asked at the end of each trial. The results revealed an interaction between linguistic and musical complexity such that the difference between the subject- and object-extracted relative clause conditions was larger in the out-of-key condition than in the in-key and auditory-anomaly conditions. These results provide evidence for an overlap in structural processing between language and music.

Abstract

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

Abstract

This study investigates word-learning using a new experimental paradigm that integrates three processes: (a) extracting a word out of a continuous sound sequence, (b) inferring its referential meanings in context, (c) mapping the segmented word onto its broader intended referent, such as other objects of the same semantic category, and to novel utterances. Previous work has examined the role of statistical learning and/or of prosody in each of these processes separately. Here, we combine these strands of investigation into a single experimental approach, in which participants viewed a photograph belonging to one of three semantic categories while hearing a complex, five-word utterance containing a target word. Six between-subjects conditions were tested with 20 adult participants each. In condition 1, the only cue to word-meaning mapping was the co-occurrence of word and referents. This statistical cue was present in all conditions. In condition 2, the target word was sounded at a higher pitch. In condition 3, random words were sounded at a higher pitch, creating an inconsistent cue. In condition 4, the duration of the target word was lengthened. In conditions 5 and 6, an extraneous acoustic cue and a visual cue were associated with the target word, respectively. Performance in this word-learning task was significantly higher than that observed with simple co-occurrence only when pitch prominence consistently marked the target word. We discuss implications for the pragmatic value of pitch marking as well as the relevance of our findings to language acquisition and language evolution.

Abstract

Rare mutations of the FOXP2 transcription factor gene cause a monogenic syndrome characterized by impaired speech development and linguistic deficits. Recent genomic investigations indicate that its downstream neural targets make broader impacts on common language impairments, bridging clinically distinct disorders. Moreover, the striking conservation of both FoxP2 sequence and neural expression in different vertebrates facilitates the use of animal models to study ancestral pathways that have been recruited towards human speech and language. Intriguingly, reduced FoxP2 dosage yields abnormal synaptic plasticity and impaired motor-skill learning in mice, and disrupts vocal learning in songbirds. Converging data indicate that Foxp2 is important for modulating the plasticity of relevant neural circuits. This body of research represents the first functional genetic forays into neural mechanisms contributing to human spoken language.

Abstract

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

Abstract

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

Relative clauses are a syntactic device to create complex sentences and they make language structurally productive. Despite a considerable number of experimental studies, it is still largely unclear how children learn relative clauses and how these are processed in the language system. Researchers at the MPI for Psycholinguistics used a computational learning model to gain novel insights into these issues. The model explains the differential development of relative clauses in English as well as cross-linguistic differences

Abstract

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

Abstract

In this study we investigated the availability of non-target language semantic features in bilingual speech processing. We recorded EEG from Dutch-English bilinguals who listened to spoken sentences in their L2 (English) or L1 (Dutch). In Experiments 1 and 3 the sentences contained an interlingual homophone. The sentence context was either biased towards the target language meaning of the homophone (target biased), the non-target language meaning (non-target biased), or neither meaning of the homophone (fully incongruent). These conditions were each compared to a semantically congruent control condition. In L2 sentences we observed an N400 in the non-target biased condition that had an earlier offset than the N400 to fully incongruent homophones. In the target biased condition, a negativity emerged that was later than the N400 to fully incongruent homophones. In L1 contexts, neither target biased nor non-target biased homophones yielded significant N400 effects (compared to the control condition). In Experiments 2 and 4 the sentences contained a language switch to a non-target language word that could be semantically congruent or incongruent. Semantically incongruent words (switched, and non-switched) elicited an N400 effect. The N400 to semantically congruent language-switched words had an earlier offset than the N400 to incongruent words. Both congruent and incongruent language switches elicited a Late Positive Component (LPC). These findings show that bilinguals activate both meanings of interlingual homophones irrespective of their contextual fit. In L2 contexts, the target-language meaning of the homophone has a head start over the non-target language meaning. The target-language head start is also evident for language switches from both L2-to-L1 and L1-to-L2

Abstract

Using eye-tracking as a window on cognitive processing, this study investigates language effects on attention to motion events in a non-verbal task. We compare gaze allocation patterns by native speakers of German and Modern Standard Arabic (MSA), two languages that differ with regard to the grammaticalization of temporal concepts. Findings of the non-verbal task, in which speakers watch dynamic event scenes while performing an auditory distracter task, are compared to gaze allocation patterns which were obtained in an event description task, using the same stimuli. We investigate whether differences in the grammatical aspectual systems of German and MSA affect the extent to which endpoints of motion events are linguistically encoded and visually processed in the two tasks. In the linguistic task, we find clear language differences in endpoint encoding and in the eye-tracking data (attention to event endpoints) as well: German speakers attend to and linguistically encode endpoints more frequently than speakers of MSA. The fixation data in the non-verbal task show similar language effects, providing relevant insights with regard to the language-and-thought debate. The present study is one of the few studies that focus explicitly on language effects related to grammatical concepts, as opposed to lexical concepts.

Abstract

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

Abstract

This chapter connects the grammar of the first person collective pronoun in the Cha’palaa language of Ecuador with its use in interaction for collective reference and social category membership attribution, addressing the problem posed by the fact that non-singular pronouns do not have distributional semantics (“speakers”) but are rather associational (“speaker and relevant associates”). It advocates a cross-disciplinary approach that jointly considers elements of linguistic form, situated usages of those forms in instances of interaction, and the broader ethnographic context of those instances. Focusing on large-scale and relatively stable categories such as racial and ethnic groups, it argues that looking at how speakers categorize themselves and others in the speech situation by using pronouns provides empirical data on the status of macro-social categories for members of a society

Abstract

In this event-related FMRI study we investigated the effect of five days of implicit acquisition on preference classification by means of an artificial grammar learning (AGL) paradigm based on the structural mere-exposure effect and preference classification using a simple right-linear unification grammar. This allowed us to investigate implicit AGL in a proper learning design by including baseline measurements prior to grammar exposure. After 5 days of implicit acquisition, the FMRI results showed activations in a network of brain regions including the inferior frontal (centered on BA 44/45) and the medial prefrontal regions (centered on BA 8/32). Importantly, and central to this study, the inclusion of a naive preference FMRI baseline measurement allowed us to conclude that these FMRI findings were the intrinsic outcomes of the learning process itself and not a reflection of a preexisting functionality recruited during classification, independent of acquisition. Support for the implicit nature of the knowledge utilized during preference classification on day 5 come from the fact that the basal ganglia, associated with implicit procedural learning, were activated during classification, while the medial temporal lobe system, associated with explicit declarative memory, was consistently deactivated. Thus, preference classification in combination with structural mere-exposure can be used to investigate structural sequence processing (syntax) in unsupervised AGL paradigms with proper learning designs.

Abstract

Stroke-induced aphasia is associated with adverse effects on quality of life and the ability to return to work. For patients and clinicians the possibility of relying on valid predictors of recovery is an important asset in the clinical management of stroke-related impairment. Age, level of education, type and severity of initial symptoms are established predictors of recovery. However, anatomical predictors are still poorly understood. In this prospective longitudinal study, we intended to assess anatomical predictors of recovery derived from diffusion tractography of the perisylvian language networks. Our study focused on the arcuate fasciculus, a language pathway composed of three segments connecting Wernicke’s to Broca’s region (i.e. long segment), Wernicke’s to Geschwind’s region (i.e. posterior segment) and Broca’s to Geschwind’s region (i.e. anterior segment). In our study we were particularly interested in understanding how lateralization of the arcuate fasciculus impacts on severity of symptoms and their recovery. Sixteen patients (10 males; mean age 60 ± 17 years, range 28–87 years) underwent post stroke language assessment with the Revised Western Aphasia Battery and neuroimaging scanning within a fortnight from symptoms onset. Language assessment was repeated at 6 months. Backward elimination analysis identified a subset of predictor variables (age, sex, lesion size) to be introduced to further regression analyses. A hierarchical regression was conducted with the longitudinal aphasia severity as the dependent variable. The first model included the subset of variables as previously defined. The second model additionally introduced the left and right arcuate fasciculus (separate analysis for each segment). Lesion size was identified as the only independent predictor of longitudinal aphasia severity in the left hemisphere [beta = −0.630, t(−3.129), P = 0.011]. For the right hemisphere, age [beta = −0.678, t(–3.087), P = 0.010] and volume of the long segment of the arcuate fasciculus [beta = 0.730, t(2.732), P = 0.020] were predictors of longitudinal aphasia severity. Adding the volume of the right long segment to the first-level model increased the overall predictive power of the model from 28% to 57% [F(1,11) = 7.46, P = 0.02]. These findings suggest that different predictors of recovery are at play in the left and right hemisphere. The right hemisphere language network seems to be important in aphasia recovery after left hemispheric stroke.

Abstract

The occipital and frontal lobes are anatomically distant yet functionally highly integrated to generate some of the most complex behaviour. A series of long associative fibres, such as the fronto-occipital networks, mediate this integration via rapid feed-forward propagation of visual input to anterior frontal regions and direct top–down modulation of early visual processing.

Despite the vast number of anatomical investigations a general consensus on the anatomy of fronto-occipital connections is not forthcoming. For example, in the monkey the existence of a human equivalent of the ‘inferior fronto-occipital fasciculus’ (iFOF) has not been demonstrated. Conversely, a ‘superior fronto-occipital fasciculus’ (sFOF), also referred to as ‘subcallosal bundle’ by some authors, is reported in monkey axonal tracing studies but not in human dissections.

In this study our aim is twofold. First, we use diffusion tractography to delineate the in vivo anatomy of the sFOF and the iFOF in 30 healthy subjects and three acallosal brains. Second, we provide a comprehensive review of the post-mortem and neuroimaging studies of the fronto-occipital connections published over the last two centuries, together with the first integral translation of Onufrowicz's original description of a human fronto-occipital fasciculus (1887) and Muratoff's report of the ‘subcallosal bundle’ in animals (1893).

Our tractography dissections suggest that in the human brain (i) the iFOF is a bilateral association pathway connecting ventro-medial occipital cortex to orbital and polar frontal cortex, (ii) the sFOF overlaps with branches of the superior longitudinal fasciculus (SLF) and probably represents an ‘occipital extension’ of the SLF, (iii) the subcallosal bundle of Muratoff is probably a complex tract encompassing ascending thalamo-frontal and descending fronto-caudate connections and is therefore a projection rather than an associative tract.

In conclusion, our experimental findings and review of the literature suggest that a ventral pathway in humans, namely the iFOF, mediates a direct communication between occipital and frontal lobes. Whether the iFOF represents a unique human pathway awaits further ad hoc investigations in animals.

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

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

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

Disruptions of the FOXP2 gene cause a rare speech and language disorder, a discovery that has opened up novel avenues for investigating the relevant neural pathways. FOXP2 shows remarkably high conservation of sequence and neural expression in diverse vertebrates, suggesting that studies in other species are useful in elucidating its functions. Here we describe how investigations of mice that carry disruptions of Foxp2 provide insights at multiple levels: molecules, cells, circuits and behaviour. Work thus far has implicated the gene in key processes including neurite outgrowth, synaptic plasticity, sensorimotor integration and motor-skill learning.

Abstract

Cumulative tool-based culture underwrote our species' evolutionary success and tool-based nut-cracking is one of the strongest candidates for cultural transmission in our closest relatives, chimpanzees. However the social learning processes that may explain both the similarities and differences between the species remain unclear. A previous study of nut-cracking by initially naïve chimpanzees suggested that a learning chimpanzee holding no hammer nevertheless replicated hammering actions it witnessed. This observation has potentially important implications for the nature of the social learning processes and underlying motor coding involved. In the present study, model and observer actions were quantified frame-by-frame and analysed with stringent statistical methods, demonstrating synchrony between the observer's and model's movements, cross-correlation of these movements above chance level and a unidirectional transmission process from model to observer. These results provide the first quantitative evidence for motor mimicking underlain by motor coding in apes, with implications for mirror neuron function.

Abstract

Previous research on language development shows that children are tuned early on to the language-specific semantic and syntactic encoding of events in their native language. Here we ask whether language-specificity is also evident in children's early representations in gesture accompanying speech. In a longitudinal study, we examined the spontaneous speech and cospeech gestures of eight Turkish-speaking children aged one to three and focused on their caused motion event expressions. In Turkish, unlike in English, the main semantic elements of caused motion such as Action and Path can be encoded in the verb (e.g. sok- ‘put in’) and the arguments of a verb can be easily omitted. We found that Turkish-speaking children's speech indeed displayed these language-specific features and focused on verbs to encode caused motion. More interestingly, we found that their early gestures also manifested specificity. Children used iconic cospeech gestures (from 19 months onwards) as often as pointing gestures and represented semantic elements such as Action with Figure and/or Path that reinforced or supplemented speech in language-specific ways until the age of three. In the light of previous reports on the scarcity of iconic gestures in English-speaking children's early productions, we argue that the language children learn shapes gestures and how they get integrated with speech in the first three years of life.

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

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

This study investigated how sentence formulation is influenced by a preceding discourse context. In two eye-tracking experiments, participants described pictures of two-character transitive events in Dutch (Experiment 1) and Chinese (Experiment 2). Focus was manipulated by presenting questions before each picture. In the Neutral condition, participants first heard ‘What is happening here?’ In the Object or Subject Focus conditions, the questions asked about the Object or Subject character (What is the policeman stopping? Who is stopping the truck?). The target response was the same in all conditions (The policeman is stopping the truck). In both experiments, sentence formulation in the Neutral condition showed the expected pattern of speakers fixating the subject character (policeman) before the object character (truck). In contrast, in the focus conditions speakers rapidly directed their gaze preferentially only to the character they needed to encode to answer the question (the new, or focused, character). The timing of gaze shifts to the new character varied by language group (Dutch vs. Chinese): shifts to the new character occurred earlier when information in the question can be repeated in the response with the same syntactic structure (in Chinese but not in Dutch). The results show that discourse affects the timecourse of linguistic formulation in simple sentences and that these effects can be modulated by language-specific linguistic structures such as parallels in the syntax of questions and declarative sentences.

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

The constraints that govern acceptable phoneme combinations in speech perception and production have considerable plasticity. We addressed whether sleep influences the acquisition of new constraints and their integration into the speech-production system. Participants repeated sequences of syllables in which two phonemes were artificially restricted to syllable onset or syllable coda, depending on the vowel in that sequence. After 48 sequences, participants either had a 90-min nap or remained awake. Participants then repeated 96 sequences so implicit constraint learning could be examined, and then were tested for constraint generalization in a forced-choice task. The sleep group, but not the wake group, produced speech errors at test that were consistent with restrictions on the placement of phonemes in training. Furthermore, only the sleep group generalized their learning to new materials. Polysomnography data showed that implicit constraint learning was associated with slow-wave sleep. These results show that sleep facilitates the integration of new linguistic knowledge with existing production constraints. These data have relevance for systems-consolidation models of sleep.

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

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

Abstract

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.