Publications

Abstract

The FOXP2 gene, located on human 7q31 (at the SPCH1 locus), encodes a transcription factor containing a polyglutamine tract and a forkhead domain. FOXP2 is mutated in a severe monogenic form of speech and language impairment, segregating within a single large pedigree, and is also disrupted by a translocation in an isolated case. Several studies of autistic disorder have demonstrated linkage to a similar region of 7q (the AUTS1 locus), leading to the proposal that a single genetic factor on 7q31 contributes to both autism and language disorders. In the present study, we directly evaluate the impact of the FOXP2 gene with regard to both complex language impairments and autism, through use of association and mutation screening analyses. We conclude that coding-region variants in FOXP2 do not underlie the AUTS1 linkage and that the gene is unlikely to play a role in autism or more common forms of language impairment.

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

In four experiments, we examined the facilitation that occurs when spoken-word targets rhyme with preceding spoken primes. In Experiment 1, listeners’ lexical decisions were faster to words following rhyming words (e.g., ramp–LAMP) than to words following unrelated primes (e.g., pink–LAMP). No facilitation was observed for nonword targets. Targets that almost rhymed with their primes (foils; e.g., bulk–SULSH) were included in Experiment 2; facilitation for rhyming targets was severely attenuated. Experiments 3 and 4 were single-word shadowing variants of the earlier experiments. There was facilitation for both rhyming words and nonwords; the presence of foils had no significant influence on the priming effect. A major component of the facilitation in lexical decision appears to be strategic: Listeners are biased to say “yes” to targets that rhyme with their primes, unless foils discourage this strategy. The nonstrategic component of phonological facilitation may reflect speech perception processes that operate prior to lexical access.

Abstract

The central thesis of the target article was that feedback is never necessary in spoken word recognition. The commentaries present no new data and no new theoretical arguments which lead us to revise this position. In this response we begin by clarifying some terminological issues which have lead to a number of significant misunderstandings. We provide some new arguments to support our case that the feedforward model Merge is indeed more parsimonious than the interactive alternatives, and that it provides a more convincing account of the data than alternative models. Finally, we extend the arguments to deal with new issues raised by the commentators such as infant speech perception and neural architecture.

Abstract

Top-down feedback does not benefit speech recognition; on the contrary, it can hinder it. No experimental data imply that feedback loops are required for speech recognition. Feedback is accordingly unnecessary and spoken word recognition is modular. To defend this thesis, we analyse lexical involvement in phonemic decision making. TRACE (McClelland & Elman 1986), a model with feedback from the lexicon to prelexical processes, is unable to account for all the available data on phonemic decision making. The modular Race model (Cutler & Norris 1979) is likewise challenged by some recent results, however. We therefore present a new modular model of phonemic decision making, the Merge model. In Merge, information flows from prelexical processes to the lexicon without feedback. Because phonemic decisions are based on the merging of prelexical and lexical information, Merge correctly predicts lexical involvement in phonemic decisions in both words and nonwords. Computer simulations show how Merge is able to account for the data through a process of competition between lexical hypotheses. We discuss the issue of feedback in other areas of language processing and conclude that modular models are particularly well suited to the problems and constraints of speech recognition.

Abstract

There is much evidence for the existence of multiple memory systems. However, it has been argued that tasks assumed to reflect different memory systems share basic processing components and are mediated by overlapping neural systems. Here we used multivariate analysis of PET-data to analyze similarities and differences in brain activity for multiple tests of working memory, semantic memory, and episodic memory. The results from two experiments revealed between-systems differences, but also between-systems similarities and within-system differences. Specifically, support was obtained for a task-general working-memory network that may underlie active maintenance. Premotor and parietal regions were salient components of this network. A common network was also identified for two episodic tasks, cued recall and recognition, but not for a test of autobiographical memory. This network involved regions in right inferior and polar frontal cortex, and lateral and medial parietal cortex. Several of these regions were also engaged during the working-memory tasks, indicating shared processing for episodic and working memory. Fact retrieval and synonym generation were associated with increased activity in left inferior frontal and middle temporal regions and right cerebellum. This network was also associated with the autobiographical task, but not with living/non-living classification, and may reflect elaborate retrieval of semantic information. Implications of the present results for the classification of memory tasks with respect to systems and/or processes are discussed.

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

Two recent studies (Coulson et al., 1998;Osterhout et al., 1996)examined the
relationship between the event-related brain potential (ERP) responses to linguistic syntactic anomalies (P600/SPS) and domain-general unexpected events (P300). Coulson et al. concluded that these responses are highly similar, whereas Osterhout et al. concluded that they are distinct. In this comment, we evaluate the relativemerits of these claims. We conclude that the available evidence indicates that the ERP response to syntactic anomalies is at least partially distinct from the ERP response to unexpected anomalies that do not involve a grammatical violation

Abstract

Two experiments examined the processing of Tokyo Japanese pitchaccent distinctions by native speakers of Japanese from two accentlessvariety areas. In both experiments, listeners were presented with Tokyo Japanese speech materials used in an earlier study with Tokyo Japanese listeners, who clearly exploited the pitch-accent information in spokenword recognition. In the "rst experiment, listeners judged from which of two words, di!ering in accentual structure, isolated syllables had been extracted. Both new groups were, overall, as successful at this task as Tokyo Japanese speakers had been, but their response patterns differed from those of the Tokyo Japanese, for instance in that a bias towards H judgments in the Tokyo Japanese responses was weakened in the present groups' responses. In a second experiment, listeners heard word fragments and guessed what the words were; in this task, the speakers from accentless areas again performed significantly above chance, but their responses showed less sensitivity to the information in the input, and greater bias towards vocabulary distribution frequencies, than had been observed with the Tokyo Japanese listeners. The results suggest that experience with a local accentless dialect affects the processing of accent for word recognition in Tokyo Japanese, even for listeners with extensive exposure to Tokyo Japanese.

Abstract

Do speakers use spontaneous gestures accompanying their speech for themselves or to communicate their message to their addressees? Two experiments show that speakers change the orientation of their gestures depending on the location of shared space, that is, the intersection of the gesture spaces of the speakers and addressees. Gesture orientations change more frequently when they accompany spatial prepositions such as into and out, which describe motion that has a beginning and end point, rather than across, which depicts an unbounded path across space. Speakers change their gestures so that they represent the beginning and end point of motion INTO or OUT by moving into or out of the shared space. Thus, speakers design their gestures for their addressees and therefore use them to communicate. This has implications for the view that gestures are a part of language use as well as for the role of gestures in speech production.

Abstract

In the present PET study we explore some functional aspects of the interaction between attentional/control processes and learning/memory processes. The network of brain regions supporting recall of abstract designs were studied in a less practiced and in a well practiced state. The results indicate that automaticity, i.e., a decreased dependence on attentional and working memory resources, develops as a consequence of practice. This corresponds to the practice related decreases of activity in the prefrontal, anterior cingulate, and posterior parietal regions. In addition, the activity of the medial temporal regions decreased as a function of practice. This indicates an inverse relation between the strength of encoding and the activation of the MTL during retrieval. Furthermore, the pattern of practice related increases in the auditory, posterior insular-opercular extending into perisylvian supra marginal region, and the right mid occipito-temporal region, may reflect a lower degree of inhibitory attentional modulation of task irrelevant processing and more fully developed representations of the abstract designs, respectively. We also suggest that free recall is dependent on bilateral prefrontal processing, in particular non-automatic free recall. The present results cofirm previous functional neuroimaging studies of memory retrieval indicating that recall is subserved by a network of interacting brain regions. Furthermore, the results indicate that some components of the neural network subserving free recall may have a dynamic role and that there is a functional restructuring of the information processing networks during the learning process.

Abstract

Recent event-related FMRI studies indicate that the prefrontal (PFC) and the medial temporal lobe (MTL) regions are more active during effective encoding than during ineffective encoding. The within-subject design and the use of well-educated young college students in these studies makes it important to replicate these results in other study populations. In this PET study, we used an auditory word-pair association cued-recall paradigm and investigated a group of healthy upper middle-aged/older illiterate women. We observed a positive correlation between cued-recall success and the regional cerebral blood flow of the left inferior PFC (BA 47) and the MTLs. Specifically, we used the cuedrecall success as a covariate in a general linear model and the results confirmed that the left inferior PFC and the MTLare more active during effective encoding than during ineffective encoding. These effects were observed during encoding of both semantically and phonologically related word pairs, indicating that these effects are robust in the studied population, that is, reproducible within group. These results generalize the results of Brewer et al. (1998, Science 281, 1185– 1187) and Wagner et al. (1998, Science 281, 1188–1191) to an upper middle aged/older illiterate population. In addition, the present study indicates that effective relational encoding correlates positively with the activity of the anterior medial temporal lobe regions.

Abstract

A fundamental problem in the study of learning is that learning-related changes may be confounded by nonspecific time effects. There are several strategies for handling this problem. This problem may be of greater significance in functional magnetic resonance imaging (fMRI) compared to positron emission tomography (PET). Using the general linear model, we describe, compare, and discuss two approaches for separating learning-related from nonspecific time effects. The first approach makes assumptions on the general behavior of nonspecific effects and explicitly models these effects, i.e., nonspecific time effects are incorporated as a linear or nonlinear confounding covariate in the statistical model. The second strategy makes no a priori assumption concerning the form of nonspecific time effects, but implicitly controls for nonspecific effects using an interaction approach, i.e., learning effects are assessed with an interaction contrast. The two approaches depend on specific assumptions and have specific limitations. With certain experimental designs, both approaches may be used and the results compared, lending particular support to effects that are independent of the method used. A third and perhaps better approach that sometimes may be practically unfeasible is to use a completely temporally balanced experimental design. The choice of approach may be of particular importance when learning related effects are studied with fMRI.

Abstract

It has been suggested that placebo analgesia involves both higher order cognitive networks and endogenous opioid systems. The rostral anterior cingulate cortex (rACC) and the brainstem are implicated in opioid analgesia, suggesting a similar role for these structures in placebo analgesia. Using positron emission tomography, we confirmed that both opioid and placebo analgesia are associated with increased activity in the rACC. We also observed a covariation between the activity in the rACC and the brainstem during both opioid and placebo analgesia, but not during the pain-only condition. These findings indicate a related neural mechanism in placebo and opioid analgesia.

Abstract

It has been suggested that placebo analgesia involves both higher order cognitive networks and endogenous opioid systems. The rostral anterior cingulate cortex (rACC) and the brainstem are implicated in opioid analgesia, suggesting a similar role for these structures in placebo analgesia. Using positron emission tomography, we confirmed that both opioid and placebo analgesia are associated with increased activity in the rACC. We also observed a covariation between the activity in the rACC and the brainstem during both opioid and placebo analgesia, but not during the pain-only condition. These findings indicate a related neural mechanism in placebo and opioid analgesia.

Abstract

The objective of this study was to investigate the central processing of dynamic mechanical allodynia in patients with mononeuropathy. Regional cerebral bloodflow, as an indicator of neuronal activity, was measured with positron emission tomography. Paired comparisons were made between three different states; rest, allodynia during brushing the painful skin area, and brushing of the homologous contralateral area. Bilateral activations were observed in the primary somatosensory cortex (S1) and the secondary somatosensory cortex (S2) during allodynia compared to rest. The S1 activation contralateral to the site of the stimulus was more expressed during allodynia than during innocuous touch. Significant activations of the contralateral posterior parietal cortex, the periaqueductal gray (PAG), the thalamus bilaterally and motor areas were also observed in the allodynic state compared to both non-allodynic states. In the anterior cingulate cortex (ACC) there was only a suggested activation when the allodynic state was compared with the non-allodynic states. In order to account for the individual variability in the intensity of allodynia and ongoing spontaneous pain, rCBF was regressed on the individually reported pain intensity, and significant covariations were observed in the ACC and the right anterior insula. Significantly decreased regional blood flow was observed bilaterally in the medial and lateral temporal lobe as well as in the occipital and posterior cingulate cortices when the allodynic state was compared to the non-painful conditions. This finding is consistent with previous studies suggesting attentional modulation and a central coping strategy for known and expected painful stimuli. Involvement of the medial pain system has previously been reported in patients with mononeuropathy during ongoing spontaneous pain. This study reveals a bilateral activation of the lateral pain system as well as involvement of the medial pain system during dynamic mechanical allodynia in patients with mononeuropathy.

Abstract

Several functional imaging studies of pain, using a number of different experimental paradigms and a variety of reference states, have failed to detect activations in the somatosensory cortices, while other imaging studies of pain have reported significant activations in these regions. The role of the somatosensory areas in pain processing has therefore been debated. In the present study the left hand was immersed in painfully cold water (standard cold pressor test) and in nonpainfully cold water during 2 min, and PET-scans were obtained either during the first or the second minute of stimulation. We observed no significant increase of activity in the somatosensory regions when the painful conditions were directly compared with the control conditions. In order to better understand the role of the primary somatosensory cortex (S1) in pain processing we used a regression analysis to study the relation between a ROI (region of interest) in the somatotopic S1-area for the stimulated hand and other regions known to be involved in pain processing. We hypothesized that although no increased activity was observed in the S1 during pain, this region would change its covariation pattern during noxious input as compared to the control stimulation if it is involved in or affected by the processing of pain. In the nonpainful cold conditions widespread regions of the ipsilateral and contralateral somatosensory cortex showed a positive covariation with the activity in the S1-ROI. However, during the first and second minute of pain this regression was significantly attenuated. During the second minute of painful stimulation there was a significant positive covariation between the activity in the S1-ROI and the other regions that are known to be involved in pain processing. Importantly, this relation was significantly stronger for the insula and the orbitofrontal cortex bilaterally when compared to the nonpainful state. The results indicate that the S1-cortex may be engaged in or affected by the processing of pain although no differential activity is observed when pain is compared with the reference condition.

Abstract

It has previously been suggested that the activity in sensory regions of the brain can be modulated by attentional mechanisms during parallel cognitive processing. To investigate whether such attention-related modulations are present in the processing of pain, the regional cerebral blood ¯ow was measured using [15O]butanol and positron emission tomography in conditions involving both pain and parallel cognitive demands. The painful stimulus consisted of the standard cold pressor test and the cognitive task was a computerised perceptual maze test. The activations during the maze test reproduced findings in previous studies of the same cognitive task. The cold pressor test evoked signi®cant activity in the contralateral S1, and bilaterally in the somatosensory association areas (including S2), the ACC and the mid-insula. The activity in the somatosensory association areas and periaqueductal gray/midbrain were significantly modified, i.e. relatively decreased, when the subjects also were performing the maze task. The altered activity was accompanied with significantly lower ratings of pain during the cognitive task. In contrast, lateral orbitofrontal regions showed a relative increase of activity during pain combined with the maze task as compared to only pain, which suggests the possibility of the involvement of frontal cortex in modulation of regions processing pain

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

When assessing dangerousness of mentally ill persons with the objective of making a decision on civil commitment, medical and legal experts use information typically belonging to their professional frame of reference. This is investigated in two studies of the commitment decision. It is hypothesized that an ‘expertise bias’ may explain differences between the medical and the legal expert in defining the dangerousness concept (study 1), and in assessing the seriousness of the danger (study 2). Judges define dangerousness more often as harming others, whereas psychiatrists more often include harm to self in the definition. In assessing the seriousness of the danger, experts tend to be more tolerant with regard to false negatives, as the type of behavior is more familiar to them. The theoretical and practical implications of the results are discussed.

Abstract

In this paper hypothesis‐testing behaviour is compared to risk‐taking behaviour. It is proposed that choosing a suitable test for a given hypothesis requires making a preposterior analysis of two aspects of such a test: the probability of obtaining supporting evidence and the evidential value of this evidence. This consideration resembles the one a gambler makes when choosing among bets, each having a probability of winning and an amount to be won. A confirmatory testing strategy can be defined within this framework as a strategy directed at maximizing either the probability or the value of a confirming outcome. Previous theories on testing behaviour have focused on the human tendency to maximize the probability of a confirming outcome. In this paper, two experiments are presented in which participants tend to maximize the confirming value of the test outcome. Motivational factors enhance this tendency dependent on the context of the testing situation. Both this result and the framework are discussed in relation to other studies in the field of testing behaviour.

Abstract

Participants performed an artificial grammar learning task, in which the standard finite
state grammar (J. Verb. Learn. Verb. Behavior 6 (1967) 855) was extended with a recursive
rule generating self-embedded sequences. We studied the learnability of such a rule in two experiments.
The results verify the general hypothesis that recursivity can be learned in an artificial
grammar learning task. However this learning seems to be rather based on recognising
chunks than on abstract rule induction. First, performance was better for strings with more
than one level of self-embedding in the sequence, uncovering more clearly the self-embedding
pattern. Second, the infinite repeatability of the recursive rule application was not spontaneously
induced from the training, but it was when an additional cue about this possibility was
given. Finally, participants were able to verbalise their knowledge of the fragments making up
the sequences––especially in the crucial front and back positions––, whereas knowledge of the
underlying structure, to the extent it was acquired, was not articulatable. The results are discussed
in relation to previous studies on the implicit learnability of complex and abstract rules.

Abstract

This study investigated characteristics of motor cortex activation and response generation in Parkinson's disease with measures of electrocortical activity (lateralized readiness potential [LRP]), electromyographic activity (EMG), and isometric force in a noise-compatibility task. When presented with stimuli consisting of incompatible target and distracter elements asking for responses of opposite hands, patients were less able than control subjects to suppress activation of the motor cortex controlling the wrong response hand. This was manifested in the pattern of reaction times and in an incorrect lateralization of the LRP. Onset latency and rise time of the LRP did not differ between patients and control subjects, but EMG and response force developed more slowly in patients. Moreover, in patients but not in control subjects, the rate of development of EMG and response force decreased as reaction time increased. We hypothesize that this dissociation between electrocortical activity and peripheral measures in Parkinson's disease is the result of changes in motor cortex function that alter the relation between signal-related and movement-related neural activity in the motor cortex. In the LRP, this altered balance may obscure an abnormal development of movement-related neural activity.

Abstract

Negation in a number of Austronesian and Papuan languages with SVO order is expressed by a rather rigid clause-final position of the negative adverb. Some typological generalizations for negation are reviewed and the distribution of this trait in languages of different stocks is discussed, arguing that it most likely originates in Papuan languages. Some proposals for different types of negation, such as whether it is a verbal (or VP) operator, a constituent operator or a sentential operator are considered. The problem of determining the scope of negation is discussed, with the conclusion that hard and fast semantic meanings for NEG at different structural levels cannot be posited, suggesting that perhaps a solution can be found in the application of some universal pragmatic principles.

Abstract

Examines the basic constituent order (BCO) on the transitive sentences in the Tenejapa dialect of Tzeltal. Concept of the basic word order; Patterns of constituent order of the transitive clauses; Consideration of VOA as the BCO.

Abstract

Santiago, MacKay, Palma, and Rho (2000) report two picture naming experiments examining the role of syllable onset complexity and number of syllables in spoken word production. Experiment 1 showed that naming latencies are longer for words with two syllables (e.g., demon ) than one syllable (e.g., duck ), and longer for words beginning with a consonant cluster (e.g., drill ) than a single consonant (e.g., duck ). Experiment 2 replicated these findings and showed that the complexity of the syllable nucleus and coda has no effect. These results are taken to support MacKay's (1987) Node Structure theory and to refute models such as WEAVER++ (Roelofs, 1997a) that predict effects of word length but not of onset complexity and number of syllables per se. In this comment, I show that a re-analysis of the data of Santiago et al. that takes word length into account leads to the opposite conclusion. The observed effects of onset complexity and number of syllables appear to be length effects, supporting WEAVER++ and contradicting the Node Structure theory.

Abstract

Minimalist theories of spoken language planning hold that articulation starts when the first
speech segment has been planned, whereas non-minimalist theories assume larger units (e.g.,
Levelt, Roelofs, & Meyer, 1999a). Three experiments are reported, which were designed to distinguish
between these views using a newhybrid task that factorially manipulated preparation and
auditory priming of spoken language production. Minimalist theories predict no effect from
priming of non-initial segments when the initial segment of an utterance is already prepared;
observing such a priming effect would support non-minimalist theories. In all three experiments,
preparation and priming yielded main effects, and together their effects were additive. Preparation
of initial segments does not eliminate priming effects for later segments. These results challenge
the minimalist view. The findings are simulated by WEAVER++ (Roelofs, 1997b), which
employs the phonological word as the lower limit for articulation initiation.

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

The control of language use has in its simplest form perhaps been most intensively studied using the color–word Stroop task. The authors review chronometric and neuroimaging evidence on Stroop task performance to evaluate two prominent, implemented models of control in naming and reading: GRAIN and WEAVER++. Computer simulations are reported, which reveal that WEAVER++ offers a more satisfactory account of the data than GRAIN. In particular, we report WEAVER++ simulations of the BOLD response in anterior cingulate cortex during Stroop performance. Aspects of single-word production and perception in the Stroop task are discussed in relation to the wider problem of the control of language use.

Abstract

The authors report a study in Dutch that used an on-line preparation paradigm to test the issue of semantic
dependency versus morphological autonomy in the production of polymorphemic words. Semantically
transparent complex words (like input in English) and semantically opaque complex words
(like invoice) showed clear evidence of morphological structure in word-form encoding, since both exhibited
an equally large preparation effect that was much greater than that for morphologically simple
words (like insect). These results suggest that morphemes may be planning units in the production of
complex words, without making a semantic contribution, thereby supporting the autonomy view. Language
production establishes itself as a domain in which morphology may operate “by itself” (Aronoff,
1994) without recourse to meaning.

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

The present paper reports an analysis of correct wh-question production and subject–auxiliary inversion errors in one child's early wh-question data (age 2; 3.4 to 4; 10.23). It is argued that two current movement rule accounts (DeVilliers, 1991; Valian, Lasser & Mandelbaum, 1992) cannot explain the patterning of early wh-questions. However, the data can be explained in terms of the child's knowledge of particular lexically-specific wh-word+auxiliary combinations, and the pattern of inversion and uninversion predicted from the relative frequencies of these combinations in the mother's speech. The results support the claim that correctly inverted wh-questions can be produced without access to a subject–auxiliary inversion rule and are consistent with the constructivist claim that a distributional learning mechanism that learns and reproduces lexically-specific formulae heard in the input can explain much of the early multi-word speech data. The implications of these results for movement rule-based and constructivist theories of grammatical development are discussed.

Abstract

Capacity limited memory systems need to gradually forget old information in order to avoid catastrophic forgetting where all stored information is lost. This can be achieved by allowing new information to overwrite old, as in the so-called palimpsest memory. This paper describes a new such learning rule employed in an attractor neural network. The network does not exhibit catastrophic forgetting, has a capacity dependent on the learning time constant and exhibits recency e!ects in retrieval

Abstract

A realtime online learning system with capacity limits needs to gradually forget old information in order to avoid catastrophic forgetting. This can be achieved by allowing new information to overwrite old, as in a so-called palimpsest memory. This paper describes an incremental learning rule based on the Bayesian confidence propagation neural network that has palimpsest properties when employed in an attractor neural network. The network does not suffer from catastrophic forgetting, has a capacity dependent on the learning time constant and exhibits faster convergence for newer patterns.

Abstract

Two experiments investigate the effect of number congruency using picture–word interference. Native German participants were required to name pictures of single objects (Nase ‘nose’) or two instances of the same object (Nasen ‘noses’) while ignoring simultaneously presented distractor words. Distractor words either had the same number or were different in number. In addition, the type of plural formation (same or different inflectional plural suffix) and the semantic relationship (same or different semantic category) between target and distractor were varied in Experiments 1 and 2. Results showed no effect of number congruency in either experiment. Furthermore, the type of inflectional suffix did not exert an influence on naming latencies in Experiment 1, but semantic relationship led to a significant interference effect in Experiment 2. The results indicate that selection of the number feature diacritic in noun production is not a competitive process. The implications of the results for models of lexical access are discussed.

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

Speakers can use pronouns when their conceptual referents are accessible from the preceding discourse, as in 'The flower is red. It turns blue'. Theories of language production agree that in order to produce a noun semantic, syntactic, and phonological information must be accessed. However, little is known about lexical access to pronouns. In this paper, we propose a model of pronoun access in German. Since the forms of German pronouns depend on the grammatical gender of the nouns they replace, the model claims that speakers must access the syntactic representation of the replaced noun (its lemma) to select a pronoun. In two experiments using the lexical decision during naming paradigm [Levelt, W.J.M., Schriefers, H., Vorberg, D., Meyer, A.S., Pechmann, T., Havinga, J., 1991a. The time course of lexical access in speech production: a study of picture naming. Psychological Review 98, 122-142], we investigated whether lemma access automatically entails the activation of the corresponding word form or whether a word form is only activated when the noun itself is produced, but not when it is replaced by a pronoun. Experiment 1 showed that during pronoun production the phonological form of the replaced noun is activated. Experiment 2 demonstrated that this phonological activation was not a residual of the use of the noun in the preceding sentence. Thus, when a pronoun is produced, the lemma and the phonological form of the replaced noun become reactivated.

Abstract

This article discusses how the Trobriand Islanders speak about body and mind. It addresses the following questions: do the linguistic datafit into theories about lexical universals of body-part terminology? Can we make inferences about the Trobrianders' conceptualization of psychological and physical states on the basis of these data? If a Trobriand Islander sees these idioms as external manifestations of inner states, then can we interpret them as a kind of ethnopsychological theory about the body and its role for emotions, knowledge, thought, memory, and so on? Can these idioms be understood as representation of Trobriand ethnopsychological theory?

Abstract

Visiting the Trobriand Islands is advertised as being the highlight of a trip for tourists to Papua New Guinea who want, and can afford, to experience this 'ultimate adventure' with 'expeditionary cruises aboard the luxurious Melanesian Discoverer. The advertisements also promise that the tourists can 'meet the friendly people' and 'observe their unique culture, dances, and art'. During my research in Kaibola and Nuwebila, two neighbouring villages on the northern tip of Kiriwina Island, I studied and analysed the encounters of tourists with Trobriand Islanders, who sing and dance for the Europeans. The analyses of the islanders' tourist performances are based on Erving Goffman's now classic study The Presentation of Self in Everyday Life, which was first published in 1959. In this study Goffmann analyses the structures of social encounters from the perspective of the dramatic performance. The situational context within which the encounter between tourists and Trobriand Islanders takes place frames the tourists as the audience and the Trobriand Islanders as a team of performers. The inherent structure of the parts of the overall performance presented in the two villages can be summarized - within the framework of Goffman's approach - in analogy with the structure of drama. We find parts that constitute the 'exposition', the 'complication', and the 'resolution' of a drama; we even observe an equivalent to the importance of the 'Second Act Curtain' in modern drama theory. Deeper analyses of this encounter show that the motives of the performers and their 'art of impression management' are to control the impression their audience receives in this encounter situation. This analysis reveals that the Trobriand Islanders sell their customers the expected images of what Malinowski (1929) once termed the '...Life of Savages in North-Western Melanesia' in a staged 'illusion'. With the conscious realization of the part they as performers play in this encounter, the Trobriand Islanders are in a position that is superior to that of their audience. Their merchandise or commodity is 'not real', as it is sold 'out of its true cultural context'. It is staged - and thus cannot be taken by any customer whatsoever because it (re)presents just an 'illusion'. The Trobriand Islanders know that neither they nor the core aspects of their culture will suffer any damage within a tourist encounter that is defined by the structure and the kind of their performance. Their pride and self-confidence enable them to bring their superior position into play in their dealings with tourists. With their indigenous humour, they even use this encounter for ridiculing their visitors. It turns out that the encounter is another manifestation of the Trobriand Islanders' self-consciousness, self-confidence, and pride with which they manage to protect core aspects of their cultural identity, while at the same time using and 'selling' parts of their culture as a kind of commodity to tourists.

Abstract

Attention-deficit/hyperactivity disorder (ADHD) is the most commonly diagnosed behavioral disorder in childhood and likely represents an extreme of normal behavior. ADHD significantly impacts learning in school-age children and leads to impaired functioning throughout the life span. There is strong evidence for a genetic etiology of the disorder, although putative alleles, principally in dopamine-related pathways suggested by candidate-gene studies, have very small effect sizes. We use affected-sib-pair analysis in 203 families to localize the first major susceptibility locus for ADHD to a 12-cM region on chromosome 16p13 (maximum LOD score 4.2; P=.000005), building upon an earlier genomewide scan of this disorder. The region overlaps that highlighted in three genome scans for autism, a disorder in which inattention and hyperactivity are common, and physically maps to a 7-Mb region on 16p13. These findings suggest that variations in a gene on 16p13 may contribute to common deficits found in both ADHD and autism.

Abstract

A quantitative model of human categorization behavior is proposed, which can be applied to 4-alternative forced-choice categorization data involving two binary classifications. A number of processing dependencies between the two classifications are explicitly formulated, such as the dependence of the location, orientation, and steepness of the class boundary for one classification on the outcome of the other classification. The significance of various types of dependencies can be tested statistically. Analyses of a data set from the literature shows that interesting dependencies in human speech recognition can be uncovered using the model.

Abstract

The temporal distribution of perceptually relevant information for consonant recognition in British English VCVs is investigated. The information distribution in the vicinity of consonantal closure and release was measured by presenting initial and final portions, respectively, of naturally produced VCV utterances to listeners for categorization. A multidimensional scaling analysis of the results provided highly interpretable, four-dimensional geometrical representations of the confusion patterns in the categorization data. In addition, transmitted information as a function of truncation point was calculated for the features manner place and voicing. The effects of speaker, vowel context, stress, and distinctive feature on the resulting information distributions were tested statistically. It was found that, although all factors are significant, the location and spread of the distributions depends principally on the distinctive feature, i.e., the temporal distribution of perceptually relevant information is very different for the features manner, place, and voicing.

Abstract

We present results from cross-modal priming experiments on German participles and noun plurals. The experiments produced parallel results for both inflectional systems. Regular inflection exhibits full priming whereas irregularly inflected word forms show only partial priming: after hearing regularly inflected words (-t participles and -s plurals), lexical decision times on morphologically related word forms (presented visually) were similar to reaction times for a base-line condition in which prime and target were identical, but significantly shorter than in a control condition where prime and target were unrelated. In contrast, prior presentation of irregular words (-n participles and -er plurals) led to significantly longer response times on morphologically related word forms than the prior presentation of the target itself. Hence, there are clear priming differences between regularly and irregularly inflected German words. We compare the findings on German with experimental results on regular and irregular inflection in English and Italian, and discuss theoretical implications for single versus dual-mechanism models of inflection.

Abstract

Spoken word recognition involves automatic activation of lexical candidates compatible with the perceived input. In running speech, words abut one another without intervening gaps, and syllable boundaries can mismatch with word boundaries. For instance, liaison in ’petit agneau’ creates a syllable beginning with a consonant although ’agneau’ begins with a vowel. In two cross-modal priming experiments we investigate how French listeners recognise words in liaison environments. These results suggest that the resolution of liaison in part depends on acoustic cues which distinguish liaison from non-liaison consonants, and in part on the availability of lexical support for a liaison interpretation.

Abstract

This study investigates whether spoken sentence comprehension deficits in Broca's aphasics results from their inability to access the subordinate meaning of ambiguous words (e.g. bank), or alternatively, from a delay in their selection of the contextually appropriate meaning. Twelve Broca's aphasics and twelve elderly controls were presented with lexical ambiguities in three context conditions, each followed by the same target words. In the concordant condition, the sentence context biased the meaning of the sentence final ambiguous word that was related to the target. In the discordant condition, the sentence context biased the meaning of the sentence final ambiguous word that was incompatible with the target.In the unrelated condition, the sentence-final word was unambiguous and unrelated to the target. The task of the subjects was to listen attentively to the stimuli The activational status of the ambiguous sentence-final words was inferred from the amplitude of the N399 to the targets at two inter-stimulus intervals (ISIs) (100 ms and 1250 ms). At the short ISI, the Broca's aphasics showed clear evidence of activation of the subordinate meaning. In contrast to elderly controls, however, the Broca's aphasics were not successful at selecting the appropriate meaning of the ambiguity in the short ISI version of the experiment. But at the long ISI, in accordance with the performance of the elderly controls, the patients were able to successfully complete the contextual selection process. These results indicate that Broca's aphasics are delayed in the process of contextual selection. It is argued that this finding of delayed selection is compatible with the idea that comprehension deficits in Broca's aphasia result from a delay in the process of integrating lexical information.

Abstract

This volume on Inuit speech follows the evolution of a native language of the North American Arctic, from its historical roots to its present-day linguistic structure and patterns of use from Alaska to Greenland. Drawing on a wide range of research from the fields of linguistics, anthropology, and sociology, Dorais integrates these diverse perspectives in a comprehensive view of native language development, maintenance, and use under conditions of marginalization due to social transition.

Abstract

Three experiments tested young children's efficiency in recognizing words in speech referring to absent objects. Seventy-two 24-month-olds heard sentences containing target words denoting objects that were or were not present in a visual display. Children's eye movements were monitored as they heard the sentences. Three distinct patterns of response were shown. Children hearing a familiar word that was an appropriate label for the currently fixated picture maintained their gaze. Children hearing a familiar word that could not apply to the currently fixated picture rapidly shifted their gaze to the alternative picture, whether that alternative was the named target or not, and then continued to search for an appropriate referent. Finally, children hearing an unfamiliar word shifted their gaze slowly and irregularly. This set of outcomes is interpreted as evidence that by 24 months, rapid activation in word recognition does not depend on the presence of the words' referents. Rather, very young children are capable of quickly and efficiently interpreting words in the absence of visual supporting context.

Abstract

The degree to which infants represent phonetic detail in words has been a source of controversy in phonology and developmental psychology. One prominent hypothesis holds that infants store words in a vague or inaccurate form until the learning of similar–sounding neighbors forces attention to subtle phonetic distinctions. In the experiment reported here, we used a visual fixation task to assess word recognition. We present the first evidence indicating that, in fact, the lexical representations of 14– and 15–month–olds are encoded in fine detail, even when this detail is not functionally necessary for distinguishing similar words in the infant’s vocabulary. Exposure to words is sufficient for well–specified lexical representations, even well before the vocabulary spurt. These results suggest developmental continuity in infants’ representations of speech: As infants begin to build a vocabulary and learn word meanings, they use the perceptual abilities previously demonstrated in tasks testing the discrimination and categorization of meaningless syllables.

Abstract

Although children's knowledge of the sound patterns of words has been a focus of debate for many years, little is known about the lexical representations very young children use in word recognition. In particular, researchers have questioned the degree of specificity encoded in early lexical representations. The current study addressed this issue by presenting 18–23-month-olds with object labels that were either correctly pronounced, or mispronounced. Mispronunciations involved replacement of one segment with a similar segment, as in ‘baby–vaby’. Children heard sentences containing these words while viewing two pictures, one of which was the referent of the sentence. Analyses of children's eye movements showed that children recognized the spoken words in both conditions, but that recognition was significantly poorer when words were mispronounced. The effects of mispronunciation on recognition were unrelated to age or to spoken vocabulary size. The results suggest that children's representations of familiar words are phonetically well-specified, and that this specification may not be a consequence of the need to differentiate similar words in production.

Abstract

The murine homologue of the human chloride channel gene, CLCN5, defects in which are responsible for Dent disease, has been cloned and characterized. We isolated the entire coding region of mouse Clcn5 cDNA and approximately 45 kb of genomic sequence embracing the gene. To study its transcriptional control, the 5' upstream sequences of the mouse Clcn5 gene were cloned into a luciferase reporter vector. Deletion analysis of 1.5 kb of the 5' flanking sequence defined an active promoter region within 128 bp of the putative transcription start site, which is associated with a TATA motif but lacks a CAAT consensus. Within this sequence, there is a motif with homology to a purine-rich sequence responsible for the kidney-specific promoter activity of the rat CLC-K1 gene, another member of the chloride-channel gene family expressed in kidney. An enhancer element that confers a 10- to 20-fold increase in the promoter activity of the mouse Clcn5 gene was found within the first intron. The organization of the human CLCN5 and mouse Clcn5 gene structures is highly conserved, and the sequence of the murine protein is 98% similar to that of human, with its highest expression seen in the kidney. This study thus provides the first identification of the transcriptional control region of, and the basis for an understanding of the regulatory mechanism that controls, this kidney-specific, chloride-channel gene.

Abstract

A growing number of researchers in the sentence processing community are using eye movements to address issues in spoken language comprehension. Experiments using this paradigm have shown that visually presented referential information, including properties of referents relevant to specific actions, influences even the earliest moments of syntactic processing. Methodological concerns about task-specific strategies and the linking hypothesis between eye movements and linguistic processing are identified and discussed. These concerns are addressed in a review of recent studies of spoken word recognition which introduce and evaluate a detailed linking hypothesis between eye movements and lexical access. The results provide evidence about the time course of lexical activation that resolves some important theoretical issues in spoken-word recognition. They also demonstrate that fixations are sensitive to properties of the normal language-processing system that cannot be attributed to task-specific strategies

Abstract

This paper presents electrophysiological data on the on-line processing of open- and closed-class words in patients with Broca’s aphasia with agrammatic comprehension. Event-related brain potentials were recorded from the scalp when Broca patients and nonaphasic control subjects were visually presented with a story in which the words appeared one at a time on the screen. Separate waveforms were computed for open- and closed-class words. The non-aphasic control subjects showed clear differences between the processing of open- and closed-class words in an early (210-375 ms) and a late (400-700 ms) time-window.The early electrophysiological differences reflect the first manifestation of the availability of word-category information from the mental lexicon. The late differences presumably relate to post-lexical semantic and syntactic processing. In contrast to the control subjects, the Broca patients showed no early vocabulary class effect and only a limited late effect. The results suggest that an important factor in the agrammatic comprehension deficit of Broca’s aphasics is a delayed and/or incomplete availability of word-class information.

Abstract

This paper presents electrophysiological evidence of an impairment in the on-line processing of word class information in patients with Broca’s aphasia with agrammatic comprehension. Event-related brain potentials (ERPs) were recorded from the scalp while Broca patients and non-aphasic control subjects read open- and closed-class words that appeared one at a time on a PC screen. Separate waveforms were computed for open- and closed-class words. The non-aphasic control subjects showed a modulation of an early left anterior negativity in the 210–325 ms as a function of vocabulary class (VC), and a late left anterior negative shift to closed-class words in the 400–700 ms epoch. An N400 effect was present in both control subjects and Broca patients. We have taken the early electrophysiological differences to reflect the first availability of word-category information from the mental lexicon. The late differences can be related to post-lexical processing. In contrast to the control subjects, the Broca patients showed no early VC effect and no late anterior shift to closed-class words. The results support the view that an incomplete and/or delayed availability of word-class information might be an important factor in Broca’s agrammatic comprehension.

Abstract

The existence of nominal classification systems has long been thought of as one of the defining features of the Papuan languages of island New Guinea. However, while almost all of these languages do have nominal classification systems, they are, in fact, extremely divergent from each other. This paper examines these systems in the East Papuan languages in order to examine the question of the relationship between these Papuan outliers. Nominal classification systems are often archaic, preserving older features lost elsewhere in a language. Also, evidence shows that they are not easily borrowed into languages (although they can be). For these reasons, it is useful to consider nominal classification systems as a tool for exploring ancient historical relationships between languages. This paper finds little evidence of relationship between the nominal classification systems of the East Papuan languages as a whole. It argues that the mere existence of nominal classification systems cannot be used as evidence that the East Papuan languages form a genetic family. The simplest hypothesis is that either the systems were inherited so long ago as to obscure the genetic evidence, or else the appearance of nominal classification systems in these languages arose through borrowing of grammatical systems rather than of morphological forms.

Abstract

This paper explores the issue of documenting an endangered language from the perspective of a community with low levels of literacy, I first discuss the background of the language community with whom I work, the Lavukal people of Solomon Islands, and discuss whether, and to what extent, Lavukaleve is an endangered language. I then go on to discuss the documentation project. My main point is that while low literacy levels and a nonreading culture would seem to make documentation a strange choice as a tool for language maintenance, in fact both serve as powerful cultural symbols of the importance and prestige of Lavukaleve. It is well known that a common reason for language death is that speakers choose not to transmit their language to the next generation (e.g. Winter 1993). Lavukaleve is particularly vulnerable in this respect. By utilizing cultural symbols of status and prestige, the standing of Lavukaleve can be enhanced, thus helping to ensure the transmission of Lavukaleve to future generations.