Publications

Abstract

Eye movements have been shown to reflect word recognition and language comprehension processes occurring during reading and auditory language comprehension. The present study examines whether the eye movements speakers make during object naming similarly reflect speech planning processes. In Experiment 1, speakers named object pairs saying, for instance, 'scooter and hat'. The objects were presented as ordinary line drawings or with partly dele:ed contours and had high or low frequency names. Contour type and frequency both significantly affected the mean naming latencies and the mean time spent looking at the objects. The frequency effects disappeared in Experiment 2, in which the participants categorized the objects instead of naming them. This suggests that the frequency effects of Experiment 1 arose during lexical retrieval. We conclude that eye movements during object naming indeed reflect linguistic planning processes and that the speakers' decision to move their eyes from one object to the next is contingent upon the retrieval of the phonological form of the object names.

Abstract

This study examined whether compensation for coarticulation in fricative–vowel syllables is phonologically mediated or a consequence of auditory processes. Smits (2001a) had shown that compensation occurs for anticipatory lip rounding in a fricative caused by a following rounded vowel in Dutch. In a first experiment, the possibility that compensation is due to general auditory processing was investigated using nonspeech sounds. These did not cause context effects akin to compensation for coarticulation, although nonspeech sounds influenced speech sound identification in an integrative fashion. In a second experiment, a possible phonological basis for compensation for coarticulation was assessed by using audiovisual speech. Visual displays, which induced the perception of a rounded vowel, also influenced compensation for anticipatory lip rounding in the fricative. These results indicate that compensation for anticipatory lip rounding in fricative–vowel syllables is phonologically mediated. This result is discussed in the light of other compensation-for-coarticulation findings and general theories of speech perception.

Abstract

We investigated how spoken words are recognized when they have been altered by phonological assimilation. Previous research has shown that there is a process of perceptual compensation for phonological assimilations. Three recently formulated proposals regarding the mechanisms for compensation for assimilation make different predictions with regard to the level at which compensation is supposed to occur as well as regarding the role of specific language experience. In the present study, Hungarian words and nonwords, in which a viable and an unviable liquid assimilation was applied, were presented to Hungarian and Dutch listeners in an identification task and a discrimination task. Results indicate that viably changed forms are difficult to distinguish from canonical forms independent of experience with the assimilation rule applied in the utterances. This reveals that auditory processing contributes to perceptual compensation for assimilation, while language experience has only a minor role to play when identification is required.

Abstract

In a series of 5 experiments, we investigated whether the processing of phonologically assimilated utterances is influenced by language learning. Previous experiments had shown that phonological assimilations, such as /lean#bacon/→[leam bacon], are compensated for in perception. In this article, we investigated whether compensation for assimilation can occur without experience with an assimilation rule using automatic event-related potentials. Our first experiment indicated that Dutch listeners compensate for a Hungarian assimilation rule. Two subsequent experiments, however, failed to show compensation for assimilation by both Dutch and Hungarian listeners. Two additional experiments showed that this was due to the acoustic properties of the assimilated utterance, confirming earlier reports that phonetic detail is important in compensation for assimilation. Our data indicate that compensation for assimilation can occur without experience with an assimilation rule, in line with phonetic–phonological theories that assume that speech production is influenced by speech-perception abilities.

Abstract

Vowel normalization in speech perception was investigated in three experiments. The range of the second formant in a carrier phrase was manipulated and this affected the perception of a target vowel in a compensatory fashion: A low F2 range in the carrier phrase made it more likely that the target vowel was perceived as a front vowel, that is, with a high F2. Recent experiments indicated that this effect might be moderated by the lexical status of the constituents of the carrier phrase. Manipulation of the lexical status in the present experiments, however, did not affect vowel normalization. In contrast, the range of vowels in the carrier phrase did influence vowel normalization. If the carrier phrase consisted of mid-to-high front vowels only, vowel categories shifted only for mid-to-high front vowels. It is argued that these results are a challenge for episodic models of word recognition.

Abstract

In everyday speech, words may be reduced. Little is known about the consequences of such reductions for spoken word comprehension. This study investigated /t/-lenition in Dutch in two corpus studies and three perceptual experiments. The production studies revealed that /t/-lenition is most likely to occur after [s] and before bilabial consonants. The perception experiments showed that listeners take into account both phonological context, phonetic detail, and the lexical status of the form in the interpretation of codas that may or may not contain a lenited word-final /t/. These results speak against models of word recognition that make hard decisions on a prelexical level.

Abstract

Understanding foreign speech is difficult, in part because of unusual mappings between sounds and words. It is known that listeners in their native language can use lexical knowledge (about how words ought to sound) to learn how to interpret unusual speech-sounds. We therefore investigated whether subtitles, which provide lexical information, support perceptual learning about foreign speech. Dutch participants, unfamiliar with Scottish and Australian regional accents of English, watched Scottish or Australian English videos with Dutch, English or no subtitles, and then repeated audio fragments of both accents. Repetition of novel fragments was worse after Dutch-subtitle exposure but better after English-subtitle exposure. Native-language subtitles appear to create lexical interference, but foreign-language subtitles assist speech learning by indicating which words (and hence sounds) are being spoken.

Abstract

Two experiments examined how Dutch listeners deal with the effects of connected-speech processes, specifically those arising from word-final /t/ reduction (e.g., whether Dutch [tas] is tas, bag, or a reduced-/t/ version of tast, touch). Eye movements of Dutch participants were tracked as they looked at arrays containing 4 printed words, each associated with a geometrical shape. Minimal pairs (e.g., tas/tast) were either both above (boven) or both next to (naast) different shapes. Spoken instructions (e.g., “Klik op het woordje tas boven de ster,” [Click on the word bag above the star]) thus became unambiguous only on their final words. Prior to disambiguation, listeners' fixations were drawn to /t/-final words more when boven than when naast followed the ambiguous sequences. This behavior reflects Dutch speech-production data: /t/ is reduced more before /b/ than before /n/. We thus argue that probabilistic knowledge about the effect of following context in speech production is used prelexically in perception to help resolve lexical ambiguities caused by continuous-speech processes.

Abstract

World knowledge influences how we perceive the world. This study shows that this influence is at least partly mediated by declarative memory. Dutch and German participants categorized hues from a yellow-to-orange continuum on stimuli that were prototypically orange or yellow and that were also associated with these color labels. Both groups gave more “yellow” responses if an ambiguous hue occurred on a prototypically yellow stimulus. The language groups were also tested on a stimulus (traffic light) that is associated with the label orange in Dutch and with the label yellow in German, even though the objective color is the same for both populations. Dutch observers categorized this stimulus as orange more often than German observers, in line with the assumption that declarative knowledge mediates the influence of world knowledge on color categorization.

Abstract

In discourse, older adults tend to be more verbose and more disfluent than young adults, especially when the task is difficult and when it places few constraints on the content of the utterance. This may be due to (a) language-specific deficits in planning the content and syntactic structure of utterances or in selecting and retrieving words from the mental lexicon, (b) a general deficit in inhibiting irrelevant information, or (c) the selection of a specific speech style. The possibility that older adults have a deficit in lexical retrieval is supported by the results of picture naming studies, in which older adults have been found to name objects less accurately and more slowly than young adults, and by the results of definition naming studies, in which older adults have been found to experience more tip-of-the-tongue (TOT) states than young adults. The available evidence suggests that these age differences are largely due to weakening of the connections linking word lemmas to phonological word forms, though adults above 70 years of age may have an additional deficit in lemma selection.

Abstract

The recognition of a word makes available its semantic and
syntactic properties. Using electrophysiological recordings, we
investigated whether one set of these properties is available
earlier than the other set. Dutch participants saw nouns on a
computer screen and performed push-button responses: In
one task, grammatical gender determined response hand
(left/right) and semantic category determined response execution
(go/no-go). In the other task, response hand depended
on semantic category, whereas response execution depended
on gender. During the latter task, response preparation occurred
on no-go trials, as measured by the lateralized
readiness potential: Semantic information was used for
response preparation before gender information inhibited
this process. Furthermore, an inhibition-related N2 effect
occurred earlier for inhibition by semantics than for inhibition
by gender. In summary, electrophysiological measures
of both response preparation and inhibition indicated that
the semantic word property was available earlier than the
syntactic word property when participants read single
words.

Abstract

Muscular hypertrophy in callipyge sheep results from a single nucleotide substitution located in the genomic interval between the imprinted Delta, Drosophila, Homolog-like 1 (DLK1) and Maternally Expressed Gene 3 (MEG3). The mechanism linking the mutation to muscle hypertrophy is unclear but involves DLK1 overexpression. The mutation is contained within CLPG1 transcripts produced from this region. Herein we show that CLPG1 is expressed prenatally in the hypertrophy-responsive longissimus dorsi muscle by all four possible genotypes, but postnatal expression is restricted to sheep carrying the mutation. Surprisingly, the mutation results in nonimprinted monoallelic transcription of CLPG1 from only the mutated allele in adult sheep, whereas it is expressed biallelically during prenatal development. We further demonstrate that local CpG methylation is altered by the presence of the mutation in longissimus dorsi of postnatal sheep. For 10 CpG sites flanking the mutation, methylation is similar prenatally across genotypes, but doubles postnatally in normal sheep. This normal postnatal increase in methylation is significantly repressed in sheep carrying one copy of the mutation, and repressed even further in sheep with two mutant alleles. The attenuation in methylation status in the callipyge sheep correlates with the onset of the phenotype, continued CLPG1 transcription, and high-level expression of DLK1. In contrast, normal sheep exhibit hypermethylation of this locus after birth and CLPG1 silencing, which coincides with DLK1 transcriptional repression. These data are consistent with the notion that the callipyge mutation inhibits perinatal nucleation of regional chromatin condensation resulting in continued elevated transcription of prenatal DLK1 levels in adult callipyge sheep. We propose a model incorporating these results that can also account for the enigmatic normal phenotype of homozygous mutant sheep.

Abstract

Children are able to take multiple perspectives in talking about entities and events. But the nature of children's sensitivities to the complex patterns of perspective-taking in adult language is unknown. We examine perspective-taking in four- and six-year-old Tamil-speaking children describing placement events, as reflected in the use of a general placement verb (veyyii ‘put’) versus two fine-grained caused posture expressions specifying orientation, either vertical (nikka veyyii ‘make stand’) or horizontal (paDka veyyii ‘make lie’). We also explore whether animacy systematically promotes shifts to a fine-grained perspective. The results show that four- and six-year-olds switch perspectives as flexibly and systematically as adults do. Animacy influences shifts to a fine-grained perspective similarly across age groups. However, unexpectedly, six-year-olds also display greater overall sensitivity to orientation, preferring the vertical over the horizontal caused posture expression. Despite early flexibility, the factors governing the patterns of perspective-taking on events are undergoing change even in later childhood, reminiscent of U-shaped semantic reorganizations observed in children's lexical knowledge. The present study points to the intriguing possibility that mechanisms that operate at the level of semantics could also influence subtle patterns of lexical choice and perspective-shifts.

Abstract

We report a genome-wide assessment of single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) in schizophrenia. We investigated SNPs using 871 patients and 863 controls, following up the top hits in four independent cohorts comprising 1,460 patients and 12,995 controls, all of European origin. We found no genome-wide significant associations, nor could we provide support for any previously reported candidate gene or genome-wide associations. We went on to examine CNVs using a subset of 1,013 cases and 1,084 controls of European ancestry, and a further set of 60 cases and 64 controls of African ancestry. We found that eight cases and zero controls carried deletions greater than 2 Mb, of which two, at 8p22 and 16p13.11-p12.4, are newly reported here. A further evaluation of 1,378 controls identified no deletions greater than 2 Mb, suggesting a high prior probability of disease involvement when such deletions are observed in cases. We also provide further evidence for some smaller, previously reported, schizophrenia-associated CNVs, such as those in NRXN1 and APBA2. We could not provide strong support for the hypothesis that schizophrenia patients have a significantly greater “load” of large (>100 kb), rare CNVs, nor could we find common CNVs that associate with schizophrenia. Finally, we did not provide support for the suggestion that schizophrenia-associated CNVs may preferentially disrupt genes in neurodevelopmental pathways. Collectively, these analyses provide the first integrated study of SNPs and CNVs in schizophrenia and support the emerging view that rare deleterious variants may be more important in schizophrenia predisposition than common polymorphisms. While our analyses do not suggest that implicated CNVs impinge on particular key pathways, we do support the contribution of specific genomic regions in schizophrenia, presumably due to recurrent mutation. On balance, these data suggest that very few schizophrenia patients share identical genomic causation, potentially complicating efforts to personalize treatment regimens.

Abstract

Specific language impairment (SLI) is a common developmental disorder haracterized by difficulties in language acquisition despite otherwise normal development and in the absence of any obvious explanatory factors. We performed a high-density screen of SLI1, a region of chromosome 16q that shows highly significant and consistent linkage to nonword repetition, a measure of phonological short-term memory that is commonly impaired in SLI. Using two independent language-impaired samples, one family-based (211 families) and another selected from a population cohort on the basis of extreme language measures (490 cases), we detected association to two genes in the SLI1 region: that encoding c-maf-inducing protein (CMIP, minP = 5.5 × 10−7 at rs6564903) and that encoding calcium-transporting ATPase, type2C, member2 (ATP2C2, minP = 2.0 × 10−5 at rs11860694). Regression modeling indicated that each of these loci exerts an independent effect upon nonword repetition ability. Despite the consistent findings in language-impaired samples, investigation in a large unselected cohort (n = 3612) did not detect association. We therefore propose that variants in CMIP and ATP2C2 act to modulate phonological short-term memory primarily in the context of language impairment. As such, this investigation supports the hypothesis that some causes of language impairment are distinct from factors that influence normal language variation. This work therefore implicates CMIP and ATP2C2 in the etiology of SLI and provides molecular evidence for the importance of phonological short-term memory in language acquisition.

Abstract

The ability to design tailored messages for specific listeners is an important aspect of
human communication. The present study investigates whether a mere belief about an
addressee’s identity influences the generation and production of a communicative message in
a novel, non-verbal communication task. Participants were made to believe they were playing a game with a child or an adult partner, while a confederate acted as both child
and adult partners with matched performance and response times. The participants’ belief
influenced their behavior, spending longer when interacting with the presumed child
addressee, but only during communicative portions of the game, i.e. using time as a tool
to place emphasis on target information. This communicative adaptation attenuated with
experience, and it was related to personality traits, namely Empathy and Need for Cognition
measures. Overall, these findings indicate that novel nonverbal communicative interactions
are selected according to a socio-centric perspective, and they are strongly
influenced by participants’ traits.

Abstract

The present study discusses psycholinguistic evidence for a difference between paradigmatic and extraparadigmatic morphology by investigating the processing of Finnish inflected and cliticized words. The data are derived from three sources of Finnish: from single-word reading performance in an agrammatic deep dyslectic speaker, as well as from visual lexical decision and wordness/learnability ratings of cliticized vs. inflected items by normal Finnish speakers. The agrammatic speaker showed awareness of the suffixes in multimorphemic words, including clitics, since he attempted to fill in this slot with morphological material. However, he never produced a clitic — either as the correct response or as an error — in any morphological configuration (simplex, derived, inflected, compound). Moreover, he produced more nominative singular errors for case-inflected nouns than he did for the cliticized words, a pattern that is expected if case-inflected forms were closely associated with their lexical heads, i.e., if they were paradigmatic and cliticized words were not. Furthermore, a visual lexical decision task with normal speakers of Finnish, showed an additional processing cost (longer latencies and more errors on cliticized than on case-inflected noun forms). Finally, a rating task indicated no difference in relative wordness between these two types of words. However, the same cliticized words were judged harder to learn as L2 items than the inflected words, most probably due to their conceptual/semantic properties, in other words due to their lack of word-level translation equivalents in SAVE languages. Taken together, the present results suggest that the distinction between paradigmatic and extraparadigmatic morphology is psychologically real.

Abstract

In linguistic theories of how sentences encode meaning, a distinction is often made between the context-free rule-based combination of lexical–semantic features of the words within a sentence (‘‘semantics’’), and the contributions made by wider context (‘‘pragmatics’’). In psycholinguistics, this distinction has led to the view that listeners initially compute a local, context-independent meaning of a phrase or sentence before relating it to the wider context. An important aspect of such a two-step perspective on interpretation is that local semantics cannot initially be overruled by global contextual factors. In two spoken-language event-related potential experiments, we tested the viability of this claim by examining whether discourse context can overrule the impact of the core lexical–semantic feature animacy, considered to be an innate organizing principle of cognition. Two-step models of interpretation predict that verb–object animacy violations, as in ‘‘The girl comforted the clock,’’ will always perturb the unfolding interpretation process, regardless of wider context. When presented in isolation, such anomalies indeed elicit a clear N400 effect, a sign of interpretive problems. However, when the anomalies were embedded in a supportive context (e.g., a girl talking to a clock about his depression), this N400 effect disappeared completely. Moreover, given a suitable discourse context (e.g., a story about an amorous peanut), animacyviolating predicates (‘‘the peanut was in love’’) were actually processed more easily than canonical predicates (‘‘the peanut was salted’’). Our findings reveal that discourse context can immediately overrule local lexical–semantic violations, and therefore suggest that language comprehension does not involve an initially context-free semantic analysis.

Abstract

Although we usually have no trouble finding the right antecedent for a pronoun, the co-reference relations between pronouns and antecedents in everyday language are often ‘formally’ ambiguous. But a pronoun is only really ambiguous if a reader or listener indeed perceives it to be ambiguous. Whether this is the case may depend on at least two factors: the language processing skills of an individual reader, and the contextual bias towards one particular referential interpretation. In the current study, we used event related brain potentials (ERPs) to explore how both these factors affect the resolution of referentially ambiguous pronouns. We compared ERPs elicited by formally ambiguous and non-ambiguous pronouns that were embedded in simple sentences (e.g., “Jennifer Lopez told Madonna that she had too much money.”). Individual differences in language processing skills were assessed with the Reading Span task, while the contextual bias of each sentence (up to the critical pronoun) had been assessed in a referential cloze pretest. In line with earlier research, ambiguous pronouns elicited a sustained, frontal negative shift relative to non-ambiguous pronouns at the group-level. The size of this effect was correlated with Reading Span score, as well as with contextual bias. These results suggest that whether a reader perceives a formally ambiguous pronoun to be ambiguous is subtly co-determined by both individual language processing skills and contextual bias.

Abstract

The reading process depends both on the text and on the reader. When we read a text, propositions in the current input are matched to propositions in the memory representation of the previous discourse but also to knowledge structures in long‐term memory. Therefore, memory‐based text processing refers both to the bottom‐up processing of the text and to the top‐down activation of the reader's knowledge. In this article, we focus on the role of cognitive structures in the reader's knowledge. We argue that causality is an important category in structuring human knowledge and that this property has consequences for text processing. Some research is discussed that illustrates that the more the information in the text reflects causal categories, the more easily the information is processed.

Abstract

Human communication has been described as involving the coding-decoding of a conventional symbol system, which could be supported by parts of the human motor system (i.e. the “mirror neurons system”). However, this view does not explain how these conventions could develop in the first place. Here we target the neglected but crucial issue of how people organize their non-verbal behavior to communicate a given intention without pre-established conventions. We have measured behavioral and brain responses in pairs of subjects during communicative exchanges occurring in a real, interactive, on-line social context. In two fMRI studies, we found robust evidence that planning new communicative actions (by a sender) and recognizing the communicative intention of the same actions (by a receiver) relied on spatially overlapping portions of their brains (the right posterior superior temporal sulcus). The response of this region was lateralized to the right hemisphere, modulated by the ambiguity in meaning of the communicative acts, but not by their sensorimotor complexity. These results indicate that the sender of a communicative signal uses his own intention recognition system to make a prediction of the intention recognition performed by the receiver. This finding supports the notion that our communicative abilities are distinct from both sensorimotor processes and language abilities.

Abstract

We propose that speech comprehension involves the activation of token representations of the phonological forms of current lexical hypotheses, separately from the ongoing construction of a conceptual interpretation of the current utterance. In a series of cross-modal priming experiments, facilitation of lexical decision responses to visual target words (e.g., time) was found for targets that were semantic associates of auditory prime words (e.g., date) when the primes were isolated words, but not when the same primes appeared in sentence contexts. Identity priming (e.g., faster lexical decisions to visual date after spoken date than after an unrelated prime) appeared, however, both with isolated primes and with primes in prosodically neutral sentences. Associative priming in sentence contexts only emerged when sentence prosody involved contrastive accents, or when sentences were terminated immediately after the prime. Associative priming is therefore not an automatic consequence of speech processing. In no experiment was there associative priming from embedded words (e.g., sedate-time), but there was inhibitory identity priming (e.g., sedate-date) from embedded primes in sentence contexts. Speech comprehension therefore appears to involve separate distinct activation both of token phonological word representations and of conceptual word representations. Furthermore, both of these types of representation are distinct from the long-term memory representations of word form and meaning.

Abstract

Participants made visual lexical decisions to upper-case words and nonwords, and then categorized an ambiguous N–H letter continuum. The lexical decision phase included different exposure conditions: Some participants saw an ambiguous letter “?”, midway between N and H, in N-biased lexical contexts (e.g., REIG?), plus words with unambiguousH(e.g., WEIGH); others saw the reverse (e.g., WEIG?, REIGN). The first group categorized more of the test continuum as N than did the second group. Control groups, who saw “?” in nonword contexts (e.g., SMIG?), plus either of the unambiguous word sets (e.g., WEIGH or REIGN), showed no such subsequent effects. Perceptual learning about ambiguous letters therefore appears to be based on lexical knowledge, just as in an analogous speech experiment (Norris, McQueen, & Cutler, 2003) which showed similar lexical influence in learning about ambiguous phonemes. We argue that lexically guided learning is an efficient general strategy available for exploitation by different specific perceptual tasks.

Abstract

We propose that word recognition in continuous speech is subject to constraints on what may constitute a viable word of the language. This Possible-Word Constraint (PWC) reduces activation of candidate words if their recognition would imply word status for adjacent input which could not be a word - for instance, a single consonant. In two word-spotting experiments, listeners found it much harder to detectapple,for example, infapple(where [f] alone would be an impossible word), than invuffapple(wherevuffcould be a word of English). We demonstrate that the PWC can readily be implemented in a competition-based model of continuous speech recognition, as a constraint on the process of competition between candidate words; where a stretch of speech between a candidate word and a (known or likely) word boundary is not a possible word, activation of the candidate word is reduced. This implementation accurately simulates both the present results and data from a range of earlier studies of speech segmentation.

Abstract

Previous research comparing detection times for syllables and for phonemes has consistently found that syllables are responded to faster than phonemes. This finding poses theoretical problems for strictly hierarchical models of speech recognition, in which smaller units should be able to be identified faster than larger units. However, inspection of the characteristics of previous experiments’stimuli reveals that subjects have been able to respond to syllables on the basis of only a partial analysis of the stimulus. In the present experiment, five groups of subjects listened to identical stimulus material. Phoneme and syllable monitoring under standard conditions was compared with monitoring under conditions in which near matches of target and stimulus occurred on no-response trials. In the latter case, when subjects were forced to analyze each stimulus fully, phonemes were detected faster than syllables.

Abstract

Speech perception requires the decoding of complex acoustic patterns. According to most cognitive models of spoken word recognition, this complexity is dealt with before lexical access via a process of abstraction from the acoustic signal to pre-lexical categories. It is currently unclear how these categories are implemented in the auditory cortex. Recent advances in animal neurophysiology and human functional imaging have made it possible to investigate the processing of speech in terms of probabilistic cortical maps rather than simple cognitive subtraction, which will enable us to relate neurometric data more directly to behavioural studies. We suggest that integration of insights from cognitive science, neurophysiology and functional imaging is necessary for furthering our understanding of pre-lexical abstraction in the cortex.

Abstract

Memorializes Martin D. S. Braine, whose research on child language acquisition and on both child and adult thinking and reasoning had a major influence on modern cognitive psychology. Addressing meaning as well as position, Braine argued that children start acquiring language by learning narrow-scope positional formulas that map components of meaning to positions in the utterance. These proposals were critical in starting discussions of the possible universality of the pivot-grammar stage and of the role of syntax, semantics,and pragmatics in children's early grammar and were pivotal to the rise of approaches in which cognitive development in language acquisition is stressed.

Abstract

The acoustic realisation of a speech sound varies, often showing allophonic variation triggered by surrounding sounds. Listeners recognise words and sounds well despite such variation, and even make use of allophonic variability in processing. This study reports five experiments on processing of the reduced/unreduced allophonic alternation of Japanese high vowels. The results show that listeners use phonological knowledge of their native language during phoneme processing and word recognition. However, interactions of the phonological and acoustic effects differ in these two processes. A facilitatory phonological effect and an inhibitory acoustic effect cancel one another out in phoneme processing; while in word recognition, the facilitatory phonological effect overrides the inhibitory acoustic effect. Four potential models of the processing of allophonic variation are discussed. The results can be accommodated in two of them, but require additional assumptions or modifications to the models, and primarily support lexical specification of allophonic variability.

Abstract

Do all components of a sign contribute equally to its recognition? In the present study, misperceptions in the sign-spotting task (based on the word-spotting task; Cutler & Norris, 1988) were analyzed to address this question. Three groups of deaf signers of British Sign Language (BSL) with different ages of acquisition (AoA) saw BSL signs combined with nonsense signs, along with combinations of two nonsense signs. They were asked to spot real signs and report what they had spotted. We will present an analysis of false alarms to the nonsense-sign combinations—that is, misperceptions of nonsense signs as real signs (cf. van Ooijen, 1996). Participants modified the movement and handshape parameters more than the location parameter. Within this pattern, however, there were differences as a function of AoA. These results show that the theoretical distinctions between form-based parameters in sign-language models have consequences for online processing. Vowels and consonants have different roles in speech recognition; similarly, it appears that movement, handshape, and location parameters contribute differentially to sign recognition.

Abstract

Prior research has indicated that readers and listeners can use information in the prior discourse to rapidly predict specific upcoming words, as the text is unfolding. Here we used event-related potentials to explore whether the ability to make rapid online predictions depends on a reader's working memory capacity (WMC). Readers with low WMC were hypothesized to differ from high WMC readers either in their overall capability to make predictions (because of their lack of cognitive resources). High and low WMC participants read highly constraining stories that supported the prediction of a specific noun, mixed with coherent but essentially unpredictive ‘prime control’ control stories that contained the same content words as the predictive stories. To test whether readers were anticipating upcoming words, critical nouns were preceded by a determiner whose gender agreed or disagreed with the gender of the expected noun. In predictive stories, both high and low WMC readers displayed an early negative deflection (300–600 ms) to unexpected determiners, which was not present in prime control stories. Only the low WMC participants displayed an additional later negativity (900–1500 ms) to unexpected determiners. This pattern of results suggests that WMC does not influence the ability to anticipate upcoming words per se, but does change the way in which readers deal with information that disconfirms the generated prediction.

Abstract

Evaluation plays a role in the telling and understanding of narratives, in communicative interaction, emotional understanding, and in psychological well-being. This article reports a study of evaluation by describing how readers monitor the concerns of characters over the course of a narrative. The main hypothesis is that readers tract the well-being via the expression of a character's internal states. Reader evaluations were revealed in think aloud protocols obtained during reading of narrative texts, one sentence at a time. Five kinds of evaluative inferences were found: appraisals (good versus bad), preferences (like versus don't like), emotions (happy versus frustrated), goals (want versus don't want), or purposes (to attain or maintain X versus to prevent or avoid X). Readers evaluated all sentences. The mean rate of evaluation per sentence was 0.55. Positive and negative evaluations over the course of the story indicated that things initially went badly for characters, improved with the formulation and execution of goal plans, declined with goal failure, and improved as characters formulated new goals and succeeded. The kind of evaluation made depended upon the episodic category of the event and the event's temporal location in the story. Evaluations also served to explain or predict events. In making evaluations, readers stayed within the frame of the story and perspectives of the character or narrator. They also moved out of the narrative frame and addressed evaluations towards the experimenter in a communicative context.

Abstract

Dyslexia is one of the most prevalent childhood cognitive disorders, affecting approximately 5% of school-age children. We have recently identified a risk haplotype associated with dyslexia on chromosome 6p22.2 which spans the TTRAP gene and portions of THEM2 and KIAA0319. Here we show that in the presence of the risk haplotype, the expression of the KIAA0319 gene is reduced but the expression of the other two genes remains unaffected. Using in situ hybridization, we detect a very distinct expression pattern of the KIAA0319 gene in the developing cerebral neocortex of mouse and human fetuses. Moreover, interference with rat Kiaa0319 expression in utero leads to impaired neuronal migration in the developing cerebral neocortex. These data suggest a direct link between a specific genetic background and a biological mechanism leading to the development of dyslexia: the risk haplotype on chromosome 6p22.2 down-regulates the KIAA0319 gene which is required for neuronal migration during the formation of the cerebral neocortex.

Abstract

The relationship between synchronous neuronal activity as measured with EEG and the blood oxygenation level dependent (BOLD) signal as measured during fMRI is not clear. This work investigates the relationship by combining EEG and fMRI measures of the strong increase in beta frequency power following movement, the so-called post-movement beta rebound (PMBR). The time course of the PMBR, as measured by EEG, was included as a regressor in the fMRI analysis, allowing identification of a region of associated BOLD signal increase in the sensorimotor cortex, with the most significant region in the post-central sulcus. The increase in the BOLD signal suggests that the number of active neurons and/or their synaptic rate is increased during the PMBR. The duration of the BOLD response curve in the PMBR region is significantly longer than in the activated motor region, and is well fitted by a model including both motor and PMBR regressors. An intersubject correlation between the BOLD signal amplitude associated with the PMBR regressor and the PMBR strength as measured with EEG provides further evidence that this region is a source of the PMBR. There is a strong intra-subject correlation between the BOLD signal amplitude in the sensorimotor cortex during movement and the PMBR strength as measured by EEG, suggesting either that the motor activity itself, or somatosensory inputs associated with the motor activity, influence the PMBR. This work provides further evidence for a BOLD signal change associated with changes in neuronal synchrony, so opening up the possibility of studying other event-related oscillatory changes using fMRI.

Abstract

Understanding the role of the medial temporal lobe (MTL) in learning and memory is an important problem in cognitive neuroscience. Memory and learning processes that depend on the function of the MTL and related diencephalic structures (e.g., the anterior and mediodorsal thalamic nuclei) are defined as declarative. We have studied the MTL activity as indicated by regional cerebral blood flow with positron emission tomography and statistical parametric mapping during recall of abstract designs in a less practiced memory state as well as in a well-practiced (well-encoded) memory state. The results showed an increased activity of the MTL bilaterally (including parahippocampal gyrus extending into hippocampus proper, as well as anterior lingual and anterior fusiform gyri) during retrieval in the less practiced memory state compared to the well-practiced memory state, indicating a dynamic role of the MTL in retrieval during the learning processes. The results also showed that the activation of the MTL decreases as the subjects learn to draw abstract designs from memory, indicating a changing role of the MTL during recall in the earlier stages of acquisition compared to the well-encoded declarative memory state.

Abstract

The irrelevant speech effect illustrates that sounds that are irrelevant to a visually presented short-term memory task still interfere with neuronal function. In the present study we explore the functional and effective connectivity of such interference. The functional connectivity analysis suggested an interaction between the level of irrelevant speech and the correlation between in particular the left superior temporal region, associated with verbal working memory, and the left medial temporal lobe. Based on this psycho-physiological interaction, and to broaden the understanding of this result, we performed a network analysis, using a simple network model for verbal working memory, to analyze its interaction with the medial temporal lobe memory system. The results showed dissociations in terms of network interactions between frontal as well as parietal and temporal areas in relation to the medial temporal lobe. The results of the present study suggest that a transition from phonological loop processing towards an engagement of episodic processing might take place during the processing of interfering irrelevant sounds. We speculate that, in response to the irrelevant sounds, this reflects a dynamic shift in processing as suggested by a closer interaction between a verbal working memory system and the medial temporal lobe memory system.

Abstract

Doubts have been cast on the strict dissociation between short- and long-term memory systems. Specifically, several neuroimaging studies have shown that the medial temporal lobe, a region almost invariably associated with long-term memory, is involved in active short-term memory maintenance. Furthermore, a recent study in hippocampally lesioned patients has shown that the hippocampus is critically involved in associating objects and their locations, even when the delay period lasts only 8 s. However, the critical feature that causes the medial temporal lobe, and in particular the hippocampus, to participate in active maintenance is still unknown. This study was designed in order to explore hippocampal involvement in active maintenance of spatial and non-spatial associations. Eighteen participants performed a delayed-match-to-sample task in which they had to maintain either object–location associations, color–number association, single colors, or single locations. Whole-brain activity was measured using event-related functional magnetic resonance imaging and analyzed using a random effects model. Right lateralized hippocampal activity was evident when participants had to maintain object–location associations, but not when they had to maintain object–color associations or single items. The present results suggest a hippocampal involvement in active maintenance when feature combinations that include spatial information have to be maintained online.

Abstract

While autism is one of the most intensively researched psychiatric disorders, little is known about reasoning skills of people with autism. The focus of this study was on defeasible inferences, that is inferences that can be revised in the light of new information. We used a behavioral task to investigate (a) conditional reasoning and (b) the suppression of conditional inferences in high-functioning adults with autism. In the suppression task a possible exception was made salient which could prevent a conclusion from being drawn. We predicted that the autism group would have difficulties dealing with such exceptions because they require mental flexibility to adjust to the context, which is often impaired in autism. The findings confirm our hypothesis that high-functioning adults with autism have a specific difficulty with exception-handling during reasoning. It is suggested that defeasible reasoning is also involved in other cognitive domains. Implications for neural underpinnings of reasoning and autism are discussed.

Abstract

Although people with autism spectrum disorders (ASD) often have severe problems with pragmatic aspects of language, little is known about their pragmatic reasoning. We carried out a behavioral study on highfunctioning adults with autistic disorder (n = 11) and Asperger syndrome (n = 17) and matched controls (n = 28) to investigate whether they are capable of deriving scalar implicatures, which are generally considered to be pragmatic inferences. Participants were presented with underinformative sentences like ‘‘Some sparrows are birds’’. This sentence is logically true, but pragmatically inappropriate if the scalar implicature ‘‘Not all sparrows are birds’’ is derived. The present findings indicate that the combined ASD group was just as likely as controls to derive scalar implicatures, yet there was a difference between participants with autistic disorder and Asperger syndrome, suggesting a potential differentiation between these disorders in pragmatic reasoning. Moreover, our results suggest that verbal intelligence is a constraint for task performance in autistic disorder but not in Asperger syndrome.

Abstract

In this study data from the first six months of 12 children s multiword speech were used to test the validity of Valian's (1991) syntactic perfor-mance-limitation account and Tomasello s (1992) verb-island account of early multiword speech with particular reference to the development of the English verb category. The results provide evidence for appropriate use of verb morphology, auxiliary verb structures, pronoun case marking, and SVO word order from quite early in development. However, they also demonstrate a great deal of lexical specificity in the children's use of these systems, evidenced by a lack of overlap in the verbs to which different morphological markers were applied, a lack of overlap in the verbs with which different auxiliary verbs were used, a disproportionate use of the first person singular nominative pronoun I, and a lack of overlap in the lexical items that served as the subjects and direct objects of transitive verbs. These findings raise problems for both a syntactic performance-limitation account and a strong verb-island account of the data and suggest the need to develop a more general lexiealist account of early multiword speech that explains why some words come to function as "islands" of organization in the child's grammar and others do not.

Abstract

In this study we test a number of different claims about the nature of stylistic variation at the “single-word” stage by examining the relation between variation in early vocabulary composition, variation in early language use, and variation in the structural and functional propreties of mothers' child-directed speech. Maternal-report and observational data were collected for 26 children at 10, 50, and 100 words, These were then correlated with a variety of different measures of maternal speech at 10 words, The results show substantial variation in the percentage of common nouns and unanalyzed phrases in children's vocabularies, and singficant relations between this variation and the way in which language is used by the child. They also reveal singficant relations between the way in whch mothers use language at 10 words and the way in chich their children use language at 50 words and between certain formal properties of mothers speech at 10 words and the percentage of common nouns and unanalyzed phrases in children's early vocabularies, However, most of these relations desappear when an attempt is made to control for ossible effects of the child on the mother at Time 1. The exception is a singficant negative correlation between mothers tendency to produce speech that illustrates word boundaries and the percentage of unanalyzed phrases at 50 and 100 words. This suggests that mothers whose sprech provides the child with information about where new words begin and end tend to have children with few unanalyzed. phrases in their early vocabularies.

Abstract

Adults and children acquire knowledge of the structure of their environment on the basis of repeated exposure to samples of structured stimuli. In the study of inductive learning, a straightforward issue is how much sample information is needed to learn the structure. The present study distinguishes between two measures for the amount of information in the sample: set size and the extent to which the set of exemplars statistically covers the underlying structure. In an artificial grammar learning experiment, learning was affected by the sample’s statistical coverage of the grammar, but not by its mere size. Our result suggests an alternative explanation of the set size effects on learning found in previous studies (McAndrews & Moscovitch, 1985; Meulemans & Van der Linden, 1997), because, as we argue, set size was confounded with statistical coverage in these studies. nt]mis|This research was supported by a grant from the Netherlands Organization for Scientific Research. We thank Jarry Porsius for his help with the data analyses.

Abstract

Learning local regularities in sequentially structured materials is typically assumed to be based on encoding of the frequencies of these regularities. We explore the view that transitional probabilities between elements of chunks, rather than frequencies of chunks, may be the primary factor in artificial grammar learning (AGL). The transitional probability model (TPM) that we propose is argued to provide an adaptive and parsimonious strategy for encoding local regularities in order to induce sequential structure from an input set of exemplars of the grammar. In a variant of the AGL procedure, in which participants estimated the frequencies of bigrams occurring in a set of exemplars they had been exposed to previously, participants were shown to be more sensitive to local transitional probability information than to mere pattern frequencies.

Abstract

GalMBP is a fragment of serum mannose-binding protein that has been modified to create a probe for galactose-containing ligands. Glycan array screening demonstrated that the carbohydrate-recognition domain of GalMBP selectively binds common groups of tumor-associated glycans, including Lewis-type structures and T antigen, suggesting that engineered glycan-binding proteins such as GalMBP represent novel tools for the characterization of glycoproteins bearing tumor-associated glycans. Blotting of cell extracts and membranes from MCF7 breast cancer cells with radiolabeled GalMBP was used to demonstrate that it binds to a selected set of high molecular weight glycoproteins that could be purified from MCF7 cells on an affinity column constructed with GalMBP. Proteomic and glycomic analysis of these glycoproteins by mass spectrometry showed that they are forms of CD98hc that bear glycans displaying heavily fucosylated termini, including Lewis(x) and Lewis(y) structures. The pool of ligands was found to include the target ligands for anti-CD15 antibodies, which are commonly used to detect Lewis(x) antigen on tumors, and for the endothelial scavenger receptor C-type lectin, which may be involved in tumor metastasis through interactions with this antigen. A survey of additional breast cancer cell lines reveals that there is wide variation in the types of glycosylation that lead to binding of GalMBP. Higher levels of binding are associated either with the presence of outer-arm fucosylated structures carried on a variety of different cell surface glycoproteins or with the presence of high levels of the mucin MUC1 bearing T antigen.

Abstract

In Greek orthography, stress position is marked with a diacritic. We investigated the developmental course of processing the stress diacritic in Grades 2 to 4. Ninety children read 108 pseudowords presented without or with a diacritic either in the same or in a different position relative to the source word. Half of the pseudowords resembled the words they were derived from. Results showed that lexical sources of stress assignment were active in Grade 2 and remained stronger than the diacritic through Grade 4. The effect of the diacritic increased more rapidly and approached the lexical effect with increasing grade. In a second experiment, 90 children read 54 words and 54 pseudowords. The pattern of results for words was similar to that for nonwords suggesting that findings regarding stress assignment using nonwords may generalize to word reading. Decoding of the diacritic does not appear to be the preferred option for developing readers.

Abstract

Greek is a language with lexical stress that marks stress orthographically with a special diacritic. Thus, the orthography and the lexicon constitute potential sources of stress assignment information in addition to any possible general default metrical pattern. Here, we report two experiments with secondary education children reading aloud pseudo-word stimuli, in which we manipulated the availability of lexical (using stimuli resembling particular words) and visual (existence and placement of the diacritic) information. The reliance on the diacritic was found to be imperfect. Strong lexical effects as well as a default metrical pattern stressing the penultimate syllable were revealed. Reading models must be extended to account for multisyllabic word reading including, in particular, stress assignment based on the interplay among multiple possible sources of information.

Abstract

To study the neural bases of semantic composition in language processing without confounds from syntactic composition, recent magnetoencephalography (MEG) studies have investigated the processing of constructions that exhibit some type of syntax-semantics mismatch. The most studied case of such a mismatch is complement coercion; expressions such as the author began the book, where an entity-denoting noun phrase is coerced into an eventive meaning in order to match the semantic properties of the event-selecting verb (e.g., ‘the author began reading/writing the book’). These expressions have been found to elicit increased activity in the Anterior Midline Field (AMF), an MEG component elicited at frontomedial sensors at ∼400 ms after the onset of the coercing noun [Pylkkänen, L., & McElree, B. (2007). An MEG study of silent meaning. Journal of Cognitive Neuroscience, 19, 11]. Thus, the AMF constitutes a potential neural correlate of coercion. However, the AMF was generated in ventromedial prefrontal regions, which are heavily associated with decision-making. This raises the possibility that, instead of semantic processing, the AMF effect may have been related to the experimental task, which was a sensicality judgment. We tested this hypothesis by assessing the effect of coercion when subjects were simply reading for comprehension, without a decision-task. Additionally, we investigated coercion in an adjectival rather than a verbal environment to further generalize the findings. Our results show that an AMF effect of coercion is elicited without a decision-task and that the effect also extends to this novel syntactic environment. We conclude that in addition to its role in non-linguistic higher cognition, ventromedial prefrontal regions contribute to the resolution of syntax-semantics mismatches in language processing.

Abstract

A fundamental and intensively discussed question is whether medial temporal lobe (MTL) processes that lead to non-associative item memories differ in their anatomical substrate from processes underlying associative memory formation. Using event-related functional magnetic resonance imaging, we implemented a novel design to dissociate brain activity related to item and associative memory formation not only by subsequent memory performance and anatomy but also in time, because the two constituents of each pair to be memorized were presented sequentially with an intra-pair delay of several seconds. Furthermore, the design enabled us to reduce potential differences in memory strength between item and associative memory by increasing task difficulty in the item recognition memory test. Confidence ratings for correct item recognition for both constituents did not differ between trials in which only item memory was correct and trials in which item and associative memory were correct. Specific subsequent memory analyses for item and associative memory formation revealed brain activity that appears selectively related to item memory formation in the posterior inferior temporal, posterior parahippocampal, and perirhinal cortices. In contrast, hippocampal and inferior prefrontal activity predicted successful retrieval of newly formed inter-item associations. Our findings therefore suggest that different MTL subregions indeed play distinct roles in the formation of item memory and inter-item associative memory as expected by several dual process models of the MTL memory system.

Abstract

The region of the ancient Sahul continent (present day Australia and New Guinea, and surrounding islands) is home to extreme linguistic diversity. Even apart from the huge Austronesian language family, which spread into the area after the breakup of the Sahul continent in the Holocene, there are hundreds of languages from many apparently unrelated families. On each of the subcontinents, the generally accepted classification recognizes one large, widespread family and a number of unrelatable smaller families. If these language families are related to each other, it is at a depth which is inaccessible to standard linguistic methods. We have inferred the history of structural characteristics of these languages under an admixture model, using a Bayesian algorithm originally developed to discover populations on the basis of recombining genetic markers. This analysis identifies 10 ancestral language populations, some of which can be identified with clearly defined phylogenetic groups. The results also show traces of early dispersals, including hints at ancient connections between Australian languages and some Papuan groups (long hypothesized, never before demonstrated). Systematic language contact effects between members of big phylogenetic groups are also detected, which can in some cases be identified with a diffusional or substrate signal. Most interestingly, however, there remains striking evidence of a phylogenetic signal, with many languages showing negligible amounts of admixture.

Abstract

Previous work has shown that illiterate subjects are better at naming two-dimensional representations of real objects when presented as colored photos as compared to black and white drawings. This raises the question if color or textural details selectively improve object recognition and naming in illiterate compared to literate subjects. In this study, we investigated whether the surface texture and/or color of objects is used to access stored object knowledge in illiterate subjects. A group of illiterate subjects and a matched literate control group were compared on an immediate object naming task with four conditions: color and black and white (i.e., grey-scaled) photos, as well as color and black and white (i.e., grey-scaled) drawings of common everyday objects. The results show that illiterate subjects perform significantly better when the stimuli are colored and this effect is independent of the photographic detail. In addition, there were significant differences between the literacy groups in the black and white condition for both drawings and photos. These results suggest that color object information contributes to object recognition. This effect was particularly prominent in the illiterate group

Abstract

A case of a word/letter dissociation is described. The present patient has a quasi-normal word reading performance (both at the level of speed and accuracy) while he has major problems in nonword and letter reading. More specifically, he has strong difficulties in retrieving letter names but preserved abilities in letter identification. This study complements previous cases reporting a similar word/letter dissociation by focusing more specifically on word reading and letter naming latencies. The results provide new constraints for modeling the role of letter knowledge within reading processes and during reading acquisition or rehabilitation.

Abstract

The adipocyte-derived protein adiponectin is highly heritable and inversely associated with risk of type 2 diabetes mellitus (T2D) and coronary heart disease (CHD). We meta-analyzed 3 genome-wide association studies for circulating adiponectin levels (n = 8,531) and sought validation of the lead single nucleotide polymorphisms (SNPs) in 5 additional cohorts (n = 6,202). Five SNPs were genome-wide significant in their relationship with adiponectin (P<} or =5x10(-8)). We then tested whether these 5 SNPs were associated with risk of T2D and CHD using a Bonferroni-corrected threshold of P{< or =0.011 to declare statistical significance for these disease associations. SNPs at the adiponectin-encoding ADIPOQ locus demonstrated the strongest associations with adiponectin levels (P-combined = 9.2x10(-19) for lead SNP, rs266717, n = 14,733). A novel variant in the ARL15 (ADP-ribosylation factor-like 15) gene was associated with lower circulating levels of adiponectin (rs4311394-G, P-combined = 2.9x10(-8), n = 14,733). This same risk allele at ARL15 was also associated with a higher risk of CHD (odds ratio [OR] = 1.12, P = 8.5x10(-6), n = 22,421) more nominally, an increased risk of T2D (OR = 1.11, P = 3.2x10(-3), n = 10,128), and several metabolic traits. Expression studies in humans indicated that ARL15 is well-expressed in skeletal muscle. These findings identify a novel protein, ARL15, which influences circulating adiponectin levels and may impact upon CHD risk.

Abstract

Rotokas is famous for possessing one of the world’s smallest phoneme inventories. According to one source, the Central dialect of Rotokas possesses only 11 segmental phonemes (five vowels and six consonants) and lacks nasals while the Aita dialect possesses a similar-sized inventory in which nasals replace voiced stops. However, recent fieldwork reveals that the Aita dialect has, in fact, both voiced and nasal stops, making for an inventory of 14 segmental phonemes (five vowels and nine consonants). The correspondences between Central and Aita Rotokas suggest that the former is innovative with respect to its consonant inventory and the latter conservative, and that the small inventory of Central Rotokas arose by collapsing the distinction between voiced and nasal stops.

Abstract

Does the spelling of a word mandatorily constrain spoken word production, or does it do so only
when spelling is relevant for the production task at hand? Damian and Bowers (2003) reported spelling
effects in spoken word production in English using a prompt–response word generation task. Preparation
of the response words was disrupted when the responses shared initial phonemes that differed
in spelling, suggesting that spelling constrains speech production mandatorily. The present experiments,
conducted in Dutch, tested for spelling effects using word production tasks in which spelling
was clearly relevant (oral reading in Experiment 1) or irrelevant (object naming and word generation
in Experiments 2 and 3, respectively). Response preparation was disrupted by spelling inconsistency
only with the word reading, suggesting that the spelling of a word constrains spoken word production
in Dutch only when it is relevant for the word production task at hand.

Abstract

In a recent series of papers, Caramazza and Miozzo [Caramazza, A., 1997. How many levels of processing are there in lexical access? Cognitive Neuropsychology 14, 177-208; Caramazza, A., Miozzo, M., 1997. The relation between syntactic and phonological knowledge in lexical access: evidence from the 'tip-of-the-tongue' phenomenon. Cognition 64, 309-343; Miozzo, M., Caramazza, A., 1997. On knowing the auxiliary of a verb that cannot be named: evidence for the independence of grammatical and phonological aspects of lexical knowledge. Journal of Cognitive Neuropsychology 9, 160-166] argued against the lemma/lexeme distinction made in many models of lexical access in speaking, including our network model [Roelofs, A., 1992. A spreading-activation theory of lemma retrieval in speaking. Cognition 42, 107-142; Levelt, W.J.M., Roelofs, A., Meyer, A.S., 1998. A theory of lexical access in speech production. Behavioral and Brain Sciences, (in press)]. Their case was based on the observations that grammatical class deficits of brain-damaged patients and semantic errors may be restricted to either spoken or written forms and that the grammatical gender of a word and information about its form can be independently available in tip-of-the-tongue stales (TOTs). In this paper, we argue that though our model is about speaking, not taking position on writing, extensions to writing are possible that are compatible with the evidence from aphasia and speech errors. Furthermore, our model does not predict a dependency between gender and form retrieval in TOTs. Finally, we argue that Caramazza and Miozzo have not accounted for important parts of the evidence motivating the lemma/lexeme distinction, such as word frequency effects in homophone production, the strict ordering of gender and pho neme access in LRP data, and the chronometric and speech error evidence for the production of complex morphology.

Abstract

In five language production experiments it was examined which aspects of words are activated in memory by context pictures and words. Context pictures yielded Stroop-like and semantic effects on response times when participants generated gender-marked noun phrases in response to written words (Experiment 1A). However, pictures yielded no such effects when participants simply read aloud the noun phrases (Experiment 2). Moreover, pictures yielded a gender congruency effect in generating gender-marked noun phrases in response to the written words (Experiments 3A and 3B). These findings suggest that context pictures activate lemmas (i.e., representations of syntactic properties), which leads to effects only when lemmas are needed to generate a response (i.e., in Experiments 1A, 3A, and 3B, but not in Experiment 2). Context words yielded Stroop-like and semantic effects in picture naming (Experiment 1B). Moreover, words yielded Stroop-like but no semantic effects in reading nouns (Experiment 4) and in generating noun phrases (Experiment 5). These findings suggest that context words activate the lemmas and forms of their names, which leads to semantic effects when lemmas are required for responding (Experiment 1B) but not when only the forms are required (Experiment 4). WEAVER++ simulations of the results are presented.

Abstract

Cognitive control includes the ability to formulate goals and plans of action and to follow these while facing distraction. Previous neuroimaging studies have shown that the presence of conflicting response alternatives in Stroop-like tasks increases activity in dorsal anterior cingulate cortex (ACC), suggesting that the ACC is involved in cognitive control. However, the exact nature of ACC function is still under debate. The prevailing conflict detection hypothesis maintains that the ACC is involved in performance monitoring. According to this view, ACC activity reflects the detection of response conflict and acts as a signal that engages regulative processes subserved by lateral prefrontal brain regions. Here, we provide evidence from functional MRI that challenges this view and favors an alternative view, according to which the ACC has a role in regulation itself. Using an arrow–word Stroop task, subjects responded to incongruent, congruent, and neutral stimuli. A critical prediction made by the conflict detection hypothesis is that ACC activity should be increased only when conflicting response alternatives are present. Our data show that ACC responses are larger for neutral than for congruent stimuli, in the absence of response conflict. This result demonstrates the engagement of the ACC in regulation itself. A computational model of Stroop-like performance instantiating a version of the regulative hypothesis is shown to account for our findings.

Abstract

Five chronometric experiments examined the functional architecture of naming dice, digits, and number words. Speakers named pictured dice, Arabic digits, or written number words, while simultaneously trying to ignore congruent or incongruent dice, digit, or number word distractors presented at various stimulus onset asynchronies (SOAs). Stroop-like interference and facilitation effects were obtained from digits and words on dice naming latencies, but not from dice on digit and word naming latencies. In contrast, words affected digit naming latencies and digits affected word naming latencies to the same extent. The peak of the interference was always around SOA = 0 ms, whereas facilitation was constant across distractor-first SOAs. These results suggest that digit naming is achieved like word naming rather than dice naming. WEAVER++simulations of the results are reported.

Abstract

Phonological encoding is the process by which speakers retrieve phonemic segments for morphemes from memory and use
the segments to assemble phonological representations of words to be spoken. When conversing in one language, bilingual
speakers have to resist the temptation of encoding word forms using the phonological rules and representations of the other
language. We argue that the activation of phonological representations is not restricted to the target language and that the
phonological representations of languages are not separate. We advance a view of bilingual control in which condition-action
rules determine what is done with the activated phonological information depending on the target language. This view is
computationally implemented in the WEAVER++ model. We present WEAVER++ simulations of the cognate facilitation effect
(Costa, Caramazza and Sebasti´an-Gall´es, 2000) and the between-language phonological facilitation effect of spoken
distractor words in object naming (Hermans, Bongaerts, de Bot and Schreuder, 1998).

Abstract

According to most models of speech production, the planning of spoken words involves the independent retrieval of segments and metrical frames followed by segment-to-frame association. In some models, the metrical frame includes a specification of the number and ordering of consonants and vowels, but in the word-form encoding by activation and verification (WEAVER) model (A. Roelofs, 1997), the frame specifies only the stress pattern across syllables. In 6 implicit priming experiments, on each trial, participants produced 1 word out of a small set as quickly as possible. In homogeneous sets, the response words shared word-initial segments, whereas in heterogeneous sets, they did not. Priming effects from shared segments depended on all response words having the same number of syllables and stress pattern, but not on their having the same number of consonants and vowels. No priming occurred when the response words had only the same metrical frame but shared no segments. Computer simulations demonstrated that WEAVER accounts for the findings.

Abstract

This article reports 7 experiments investigating whether utterances are planned in a parallel or rightward incremental fashion during language production. The experiments examined the role of linear order, length, frequency, and repetition in producing Dutch verb–particle combinations. On each trial, participants produced 1 utterance out of a set of 3 as quickly as possible. The responses shared part of their form or not. For particle-initial infinitives, facilitation was obtained when the responses shared the particle but not when they shared the verb. For verb-initial imperatives, however, facilitation was obtained for the verbs but not for the particles. The facilitation increased with length, decreased with frequency, and was independent of repetition. A simple rightward incremental model accounts quantitatively for the results.

Abstract

Lexical access in speaking consists of two major steps: lemma retrieval and word-form encoding. In Roelofs (Roelofs, A. 1992a. Cognition 42. 107-142; Roelofs. A. 1993. Cognition 47, 59-87.), I described a model of lemma retrieval. The present paper extends this work by presenting a comprehensive model of the second access step, word-form encoding. The model is called WEAVER (Word-form Encoding by Activation and VERification). Unlike other models of word-form generation, WEAVER is able to provide accounts of response time data, particularly from the picture-word interference paradigm and the implicit priming paradigm. Its key features are (1) retrieval by spreading activation, (2) verification of activated information by a production rule, (3) a rightward incremental construction of phonological representations using a principle of active syllabification, syllables are constructed on the fly rather than stored with lexical items, (4) active competitive selection of syllabic motor programs using a mathematical formalism that generates response times and (5) the association of phonological speech errors with the selection of syllabic motor programs due to the failure of verification.

Abstract

Purpose: The study of auxiliary acquisition is central to work on language development and has attracted theoretical work from both nativist and constructivist approaches. This study is part of a 2-part companion set that represents a unique attempt to trace the development of auxiliary syntax by using a longitudinal elicitation methodology. The aim of the research described in this part is to track the development of modal auxiliaries and auxiliary DO in questions and declaratives to provide a more complete picture of the development of the auxiliary system in English-speaking children. Method: Twelve English-speaking children participated in 2 tasks designed to elicit auxiliaries CAN, WILL, and DOES in declaratives and yes/no questions. They completed each task 6 times in total between the ages of 2;10 (years;months) and 3;6. Results: The children’s levels of correct use of the target auxiliaries differed in complex ways according to auxiliary, polarity, and sentence structure, and these relations changed over development. An analysis of the children’s errors also revealed complex interactions between these factors. Conclusions: These data cannot be explained in full by existing theories of auxiliary acquisition. Researchers working within both generativist and constructivist frameworks need to develop more detailed theories of acquisition that predict the pattern of acquisition observed.

Abstract

Studies based on naturalistic data are a core tool in the field of language acquisition research and have provided thorough descriptions of children's speech. However, these descriptions are inevitably confounded by differences in the relative frequency with which children use words and language structures. The purpose of the present work was to investigate the impact of sampling constraints on estimates of the productivity of children's utterances, and on the validity of error rates. Comparisons were made between five different sized samples of wh-question data produced by one child aged 2;8. First, we assessed whether sampling constraints undermined the claim (e.g. Tomasello, 2000) that the restricted nature of early child speech reflects a lack of adultlike grammatical knowledge. We demonstrated that small samples were equally likely to under- as overestimate lexical specificity in children's speech, and that the reliability of estimates varies according to sample size. We argued that reliable analyses require a comparison with a control sample, such as that from an adult speaker. Second, we investigated the validity of estimates of error rates based on small samples. The results showed that overall error rates underestimate the incidence of error in some rarely produced parts of the system and that analyses on small samples were likely to substantially over- or underestimate error rates in infrequently produced constructions. We concluded that caution must be used when basing arguments about the scope and nature of errors in children's early multi-word productions on analyses of samples of spontaneous speech.

Abstract

A key mechanism in the organization of turns at talk in conversation is the ability to anticipate or PROJECT the moment of completion of a current speaker’s turn. Some authors suggest that this is achieved via lexicosyntactic cues, while others argue that projection is based on intonational contours. We tested these hypotheses in an on-line experiment, manipulating the presence of symbolic (lexicosyntactic) content and intonational contour of utterances recorded in natural conversations. When hearing the original recordings, subjects can anticipate turn endings with the same degree of accuracy attested in real conversation. With intonational contour entirely removed (leaving intact words and syntax, with a completely flat pitch), there is no change in subjects’ accuracy of end-of-turn projection. But in the opposite case (with original intonational contour intact, but with no recognizable words), subjects’ performance deteriorates significantly. These results establish that the symbolic (i.e. lexicosyntactic) content of an utterance is necessary (and possibly sufficient) for projecting the moment of its completion, and thus for regulating conversational turn-taking. By contrast, and perhaps surprisingly, intonational contour is neither necessary nor sufficient for end-of-turn projection.

Abstract

As Rose (2006) discusses in the lead article, two camps can be identified in the field of gesture research: those who believe that gesticulation enhances communication by providing extra information to the listener, and on the other hand those who believe that gesticulation is not communicative, but rather that it facilitates speaker-internal word finding processes. I review a number of key studies relevant for this controversy, and conclude that the available empirical evidence is supporting the notion that gesture is a communicative device which can compensate for problems in speech by providing information in gesture. Following that, I discuss the finding by Rose and Douglas (2001) that making gestures does facilitate word production in some patients with aphasia. I argue that the gestures produced in the experiment by Rose and Douglas are not guaranteed to be of the same kind as the gestures that are produced spontaneously under naturalistic, communicative conditions, which makes it difficult to generalise from that particular study to general gesture behavior. As a final point, I encourage researchers in the area of aphasia to put more emphasis on communication in naturalistic contexts (e.g., conversation) in testing the capabilities of people with aphasia.

Abstract

This article reports on the analysis of prosodic marking of topical referents in the German prefield by 5- and 7-year-old children and adults. Natural speech data was obtained from a picture-elicited narration task. The data was analyzed both phonologically and phonetically. In line with previous findings, adult speakers realized topical referents predominantly with the accents L+H* and L*+H, but H* accents and unaccented items were also observed. Children used the same accent types as adults, but the accent types were distributed differently. Also, children aligned pitch minima earlier than adults and produced accents with a decreased speed of pitch change. Possible reasons for these findings are discussed. Contrast – defined in terms of a change of subjecthood – did not affect the choice of pitch accent type and did not influence phonetic realization, underlining the fact that accentuation is often a matter of individual speaker choice.

Abstract

PET and fMRI experiments have previously shown that several brain regions in the frontal and parietal lobe are involved in working memory maintenance. MEG and EEG experiments have shown parametric increases with load for oscillatory activity in posterior alpha and frontal theta power. In the current study we investigated whether the areas found with fMRI can be associated with these alpha and theta effects by measuring simultaneous EEG and fMRI during a modified Sternberg task This allowed us to correlate EEG at the single trial level with the fMRI BOLD signal by forming a regressor based on single trial alpha and theta
power estimates. We observed a right posterior, parametric alpha power increase, which was functionally related to decreases in BOLD in the primary visual cortex and in the posterior part of the right middle temporal gyrus. We relate this finding to the inhibition of neuronal activity that may interfere with WM maintenance. An observed parametric increase in frontal theta power was correlated to a decrease in BOLD in
regions that together form the default mode network. We did not observe correlations between oscillatory EEG phenomena and BOLD in the traditional WM areas. In conclusion, the study shows that simultaneous EEG fMRI recordings can be successfully used to identify the emergence of functional networks in the brain during the execution of a cognitive task.

Abstract

An event-related brain potentials (ERP) experiment was carried out to investigate the influence of semantic category membership on syntactic decision-making. Native speakers of German viewed a series of words that were semantically marked or unmarked for gender and made go/no-go decisions about the grammatical gender of those words. The electrophysiological results indicated that participants could make a gender decision earlier when words were semantically gender-marked than when they were semantically gender-unmarked. Our data provide evidence for the influence of semantic category membership on the decision of the syntactic gender of a visually presented German noun. More specifically, our results support models of language comprehension in which semantic information processing of words is initiated prior to syntactic information processing is finalized.

Abstract

Freestanding and bound morphemes differ in many (psycho)linguistic aspects. Some theorists have claimed that the representation and retrieval of freestanding and bound morphemes in the course of language production are governed by similar processing mechanisms. Alternatively, it has been proposed that both types of morphemes may be selected for production in different ways. In this article, the authors first review the available experimental evidence related to this topic and then present new experimental data pointing to the notion that freestanding and bound morphemes are retrieved following distinct processing principles: freestanding morphemes are subject to competition, bound morphemes not.

Abstract

An event-related brain potentials (ERPs) experiment was carried out to investigate the time course of lexical stress encoding in language production. Native speakers of Dutch viewed a series of pictures corresponding to bisyllabic names which were either stressed on the first or on the second syllable and made go/no-go decisions on the lexical stress location of those picture names. Behavioral results replicated a pattern that was observed earlier, i.e. faster button-press latencies to initial as compared to final stress targets. The electrophysiological results indicated that participants could make a lexical stress decision significantly earlier when picture names had initial than when they had final stress. Moreover, the present data suggest the time course of lexical stress encoding during single word form formation in language production. When word length is corrected for, the temporal interval for lexical stress encoding specified by the current ERP results falls into the time window previously identified for phonological encoding in language production.

Abstract

This study investigated the monitoring of metrical stress information in internally generated speech. In Experiment 1, Dutch participants were asked to judge whether bisyllabic picture names had initial or final stress. Results showed significantly faster decision times for initially stressed targets (e.g., KAno ‘‘canoe’’) than for targets with final stress (e.g., kaNON ‘‘cannon’’; capital letters indicate stressed syllables). It was demonstrated that monitoring latencies are not a function of the picture naming or object recognition latencies to the same pictures. Experiments 2 and 3 replicated the outcome of the first experiment with trisyllabic picture names. These results are similar to the findings of Wheeldon and Levelt (1995) in a segment monitoring task. The outcome might be interpreted to demonstrate that phonological encoding in speech production is a rightward incremental process. Alternatively, the data might reflect the sequential nature of a perceptual mechanism used to monitor lexical stress.

Abstract

In this study, we investigated grammatical feature selection during noun phrase production in Dutch. More specifically, we studied the conditions under which different grammatical genders select either the same or different determiners. Pictures of simple objects paired with a gender-congruent or a gender-incongruent distractor word were presented. Participants named the pictures using a noun phrase with the appropriate gender-marked determiner. Auditory (Experiment 1) or visual cues (Experiment 2) indicated whether the noun was to be produced in its standard or diminutive form. Results revealed a cost in naming latencies when target and distractor take different determiner forms independent of whether or not they have the same gender. This replicates earlier results showing that congruency effects are due to competition during the selection of determiner forms rather than gender features. The overall pattern of results supports the view that grammatical feature selection is an automatic consequence of lexical node selection and therefore not subject to interference from incongruent grammatical features. Selection of the correct determiner form, however, is a competitive process, implying that lexical node and grammatical feature selection operate with distinct principles.

Abstract

When we perceive speech, our goal is to extract the meaning of the verbal message which includes semantic processing. However, how deeply do we process speech in different situations? In two experiments, native Dutch participants heard spoken sentences describing simultaneously presented pictures. Sentences either correctly described the pictures or contained an anomalous final word (i.e. a semantically or phonologically incongruent word). In the first experiment, spoken sentences were task-irrelevant and both anomalous conditions elicited similar centro-parietal N400s that were larger in amplitude than the N400 for the correct condition. In the second experiment, we ensured that participants processed the same stimuli semantically. In an early time window, we found similar phonological mismatch negativities for both anomalous conditions compared to the correct condition. These negativities were followed by an N400 that was larger for semantic than phonological errors. Together, these data suggest that we process speech semantically, even if the speech is task-irrelevant. Once listeners allocate more cognitive resources to the processing of speech, we suggest that they make predictions for upcoming words, presumably by means of the production system and an internal monitoring loop, to facilitate lexical processing of the perceived speech

Abstract

To investigate the role of the syllable in Dutch speech production, five experiments were carried out to examine the effect of visually masked syllable primes on the naming latencies for written words and pictures. Targets had clear syllable boundaries and began with a CV syllable (e.g., ka.no) or a CVC syllable (e.g., kak.tus), or had ambiguous syllable boundaries and began with a CV[C] syllable (e.g., ka[pp]er). In the syllable match condition, bisyllabic Dutch nouns or verbs were preceded by primes that were identical to the target’s first syllable. In the syllable mismatch condition, the prime was either shorter or longer than the target’s first syllable. A neutral condition was also included. None of the experiments showed a syllable priming effect. Instead, all related primes facilitated the naming of the targets. It is concluded that the syllable does not play a role in the process of phonological encoding in Dutch. Because the amount of facilitation increased with increasing overlap between prime and target, the priming effect is accounted for by a segmental overlap hypothesis.

Abstract

A series of experiments was carried out to investigate the syllable affiliation of intervocalic consonants following short vowels, long vowels, and schwa in Dutch. Special interest was paid to words such as letter ['leter] ''id.,'' where a short vowel is followed by a single consonant. On phonological grounds one may predict that the first syllable should always be closed, but earlier psycholinguistic research had shown that speakers tend to leave these syllables open. In our experiments, bisyllabic word forms were presented aurally, and participants produced their syllables in reversed order (Experiments 1 through 5), or repeated the words inserting a pause between the syllables (Experiment 6). The results showed that participants generally closed syllables with a short vowel. However, in a significant number of the cases they produced open short vowel syllables. Syllables containing schwa, like syllables with a long vowel, were hardly ever closed. Word stress, the phonetic quality of the vowel in the first syllable, and the experimental context influenced syllabification. Taken together, the experiments show that native speakers syllabify bisyllabic Dutch nouns in accordance with a small set of prosodic output constraints. To account for the variability of the results, we propose that these constraints differ in their probabilities of being applied.

Abstract

Interactions between functionally specialized brain regions are crucial for normal brain function. Magnetoencephalography (MEG) and electroencephalography (EEG) are techniques suited to capture these interactions, because they provide whole head measurements of brain activity in the millisecond range. More than one sensor picks up the activity of an underlying source. This field spread severely limits the utility of connectivity measures computed directly between sensor recordings. Consequentially, neuronal interactions should be studied on the level of the reconstructed sources. This article reviews several methods that have been applied to investigate interactions between brain regions in source space. We will mainly focus on the different measures used to quantify connectivity, and on the different strategies adopted to identify regions of interest. Despite various successful accounts of MEG and EEG source connectivity, caution with respect to the interpretation of the results is still warranted. This is due to the fact that effects of field spread can never be completely abolished in source space. However, in this very exciting and developing field of research this cautionary note should not discourage researchers from further investigation into the connectivity between neuronal sources.

Abstract

This paper combines acoustic features with a high temporal and a high frequency resolution to reliably classify articulatory events of short duration, such as bursts in plosives. SVM classification experiments on TIMIT and SVArticulatory showed that articulatory-acoustic features (AFs) based on a combination of MFCCs derived from a long window of 25ms and a short window of 5ms that are both shifted with 2.5ms steps (Both) outperform standard MFCCs derived with a window of 25 ms and a shift of 10 ms (Baseline). Finally, comparison of the TIMIT and SVArticulatory results showed that for classifiers trained on data that allows for asynchronously changing AFs (SVArticulatory) the improvement from Baseline to Both is larger than for classifiers trained on data where AFs change simultaneously with the phone boundaries (TIMIT).

Abstract

The motor theory of speech perception assumes that activation of the motor system is essential in the perception of speech. However, deficits in speech perception and comprehension do not arise from damage that is restricted to the motor cortex, few functional imaging studies reveal activity in motor cortex during speech perception, and the motor cortex is strongly activated by many different sound categories. Here, we evaluate alternative roles for the motor cortex in spoken communication and suggest a specific role in sensorimotor processing in conversation. We argue that motor-cortex activation it is essential in joint speech, particularly for the timing of turn-taking.

Abstract

Bipolar disorder (BP) is a disabling and often life-threatening disorder that affects approximately 1% of the population worldwide. To identify genetic variants that increase the risk of BP, we genotyped on the Illumina HumanHap550 Beadchip 2,076 bipolar cases and 1,676 controls of European ancestry from the National Institute of Mental Health Human Genetics Initiative Repository, and the Prechter Repository and samples collected in London, Toronto, and Dundee. We imputed SNP genotypes and tested for SNP-BP association in each sample and then performed meta-analysis across samples. The strongest association P value for this 2-study meta-analysis was 2.4 x 10(-6). We next imputed SNP genotypes and tested for SNP-BP association based on the publicly available Affymetrix 500K genotype data from the Wellcome Trust Case Control Consortium for 1,868 BP cases and a reference set of 12,831 individuals. A 3-study meta-analysis of 3,683 nonoverlapping cases and 14,507 extended controls on >2.3 M genotyped and imputed SNPs resulted in 3 chromosomal regions with association P approximately 10(-7): 1p31.1 (no known genes), 3p21 (>25 known genes), and 5q15 (MCTP1). The most strongly associated nonsynonymous SNP rs1042779 (OR = 1.19, P = 1.8 x 10(-7)) is in the ITIH1 gene on chromosome 3, with other strongly associated nonsynonymous SNPs in GNL3, NEK4, and ITIH3. Thus, these chromosomal regions harbor genes implicated in cell cycle, neurogenesis, neuroplasticity, and neurosignaling. In addition, we replicated the reported ANK3 association results for SNP rs10994336 in the nonoverlapping GSK sample (OR = 1.37, P = 0.042). Although these results are promising, analysis of additional samples will be required to confirm that variant(s) in these regions influence BP risk.

Abstract

Using kinetic contours derived from everyday objects, we investigated how motion affects object identification. In order not to be distinguishable when static, kinetic contours were made from random dot displays consisting of two regions, inside and outside the object contour. In Experiment 1, the dots were moving in only one of two regions. The objects were identified nearly equally well as soon as the dots either in the figure or in the background started to move. RTs decreased with increasing motion coherence levels and were shorter for complex, less compact objects than for simple, more compact objects. In Experiment 2, objects could be identified when the dots were moving both in the figure and in the background with speed and direction differences between the two. A linear increase in either the speed difference or the direction difference caused a linear decrease in RT for correct identification. In addition, the combination of speed and motion differences appeared to be super-additive.

Abstract

French-learning 11-month-old and English-learning 11- and 4-month-old infants were familiarized with consonant–vowel–consonant syllables in which the final consonants were dependent on whether the preceding vowel was oral or nasal. Oral and nasal vowels are present in the ambient language of all participants, but vowel nasality is phonemic (contrastive) in French and allophonic (noncontrastive) in English. After familiarization, infants heard novel syllables that either followed or violated the familiarized patterns. French-learning 11-month-olds and English-learning 4-month-olds displayed a reliable pattern of preference demonstrating learning and generalization of the patterns, while English-learning 11-month-olds oriented equally to syllables following and violating the familiarized patterns. The results are consistent with an experience-driven reduction of attention to allophonic contrasts by as early as 11 months, which influences phonotactic learning.

Abstract

In a landmark study, Jusczyk and Aslin (1995) demonstrated that English-learning infants are able to segment words from continuous speech at 7.5 months of age. In the current study, we explored the possibility that infants segment words from the edges of utterances more readily than the middle of utterances. The same procedure was used as in Jusczyk and Aslin (1995); however, our stimuli were controlled for target word location and infants were given a shorter familiarization time to avoid ceiling effects. Infants were familiarized to one word that always occurred at the edge of an utterance (sentence-initial position for half of the infants and sentence-final position for the other half) and one word that always occurred in sentence-medial position. Our results demonstrate that infants segment words from the edges of an utterance more readily than from the middle of an utterance. In addition, infants segment words from utterance-final position just as readily as they segment words from utterance-initial position. Possible explanations for these results, as well as their implications for current models of the development of word segmentation, are discussed.