Publications

Abstract

The time course of spoken word recognition depends largely on the frequencies of a word and its competitors, or neighbors (similar-sounding words). However, variability in natural lexicons makes systematic analysis of frequency and neighbor similarity difficult. Artificial lexicons were used to achieve precise control over word frequency and phonological similarity. Eye tracking provided time course measures of lexical activation and competition (during spoken instructions to perform visually guided tasks) both during and after word learning, as a function of word frequency, neighbor type, and neighbor frequency. Apparent shifts from holistic to incremental competitor effects were observed in adults and neural network simulations, suggesting such shifts reflect general properties of learning rather than changes in the nature of lexical representations.

Abstract

The human capacity for acquiring speech and language must derive, at least in part, from the genome. In 2001, a study described the first case of a gene, FOXP2, which is thought to be implicated in our ability to acquire spoken language. In the present article, we discuss how this gene was discovered, what it might do, how it relates to other genes, and what it could tell us about the nature of speech and language development. We explain how FOXP2 could, without being specific to the brain or to our own species, still provide an invaluable entry-point into understanding the genetic cascades and neural pathways that contribute to our capacity for speech and language.

Abstract

Replication of linkage results for complex traits has been exceedingly difficult, owing in part to the inability to measure the precise underlying phenotype, small sample sizes, genetic heterogeneity, and statistical methods employed in analysis. Often, in any particular study, multiple correlated traits have been collected, yet these have been analyzed independently or, at most, in bivariate analyses. Theoretical arguments suggest that full multivariate analysis of all available traits should offer more power to detect linkage; however, this has not yet been evaluated on a genomewide scale. Here, we conduct multivariate genomewide analyses of quantitative-trait loci that influence reading- and language-related measures in families affected with developmental dyslexia. The results of these analyses are substantially clearer than those of previous univariate analyses of the same data set, helping to resolve a number of key issues. These outcomes highlight the relevance of multivariate analysis for complex disorders for dissection of linkage results in correlated traits. The approach employed here may aid positional cloning of susceptibility genes in a wide spectrum of complex traits.

Abstract

Magnuson, McMurray, Tanenhaus, and Aslin [Cogn. Sci. 27 (2003) 285] suggest that they have evidence of lexical feedback in speech perception, and that this evidence thus challenges the purely feedforward Merge model [Behav. Brain Sci. 23 (2000) 299]. This evidence is open to an alternative explanation, however, one which preserves the assumption in Merge that there is no lexical-prelexical feedback during on-line speech processing. This explanation invokes the distinction between perceptual processing that occurs in the short term, as an utterance is heard, and processing that occurs over the longer term, for perceptual learning.

Abstract

Spoken word recognition consists of two major component processes. First, at the prelexical stage, an abstract description of the utterance is generated from the information in the speech signal. Second, at the lexical stage, this description is used to activate all the words stored in the mental lexicon which match the input. These multiple candidate words then compete with each other. We review evidence which suggests that positive (match) and negative (mismatch) information of both a segmental and a suprasegmental nature is used to constrain this activation and competition process. We then ask whether, in addition to the necessary influence of the prelexical stage on the lexical stage, there is also feedback from the lexicon to the prelexical level. In two phonetic categorization experiments, Dutch listeners were asked to label both syllable-initial and syllable-final ambiguous fricatives (e.g., sounds ranging from [f] to [s]) in the word–nonword series maf–mas, and the nonword–word series jaf–jas. They tended to label the sounds in a lexically consistent manner (i.e., consistent with the word endpoints of the series). These lexical effects became smaller in listeners’ slower responses, even when the listeners were put under pressure to respond as fast as possible. Our results challenge models of spoken word recognition in which feedback modulates the prelexical analysis of the component sounds of a word whenever that word is heard

Abstract

In 5 experiments, listeners heard words and nonwords, some cross-spliced so that they contained acoustic-phonetic mismatches. Performance was worse on mismatching than on matching items. Words cross-spliced with words and words cross-spliced with nonwords produced parallel results. However, in lexical decision and 1 of 3 phonetic decision experiments, performance on nonwords cross-spliced with words was poorer than on nonwords cross-spliced with nonwords. A gating study confirmed that there were misleading coarticulatory cues in the cross-spliced items; a sixth experiment showed that the earlier results were not due to interitem differences in the strength of these cues. Three models of phonetic decision making (the Race model, the TRACE model, and a postlexical model) did not explain the data. A new bottom-up model is outlined that accounts for the findings in terms of lexical involvement at a dedicated decision-making stage.

Abstract

On the basis of evidence from studies of the naming and reading of numerals, Ferrand (1999) argued that the naming of objects is slower than reading their names, due to a greater response uncertainty in naming than in reading, rather than to an obligatory conceptual preparation for naming, but not for reading. We manipulated the need for conceptual preparation, while keeping response uncertainty constant in the naming and reading of complex numerals. In Experiment 1, participants named three-digit Arabic numerals either as house numbers or clock times. House number naming latencies were determined mostly by morphophonological factors, such as morpheme frequency and the number of phonemes, whereas clock time naming latencies revealed an additional conceptual involvement. In Experiment 2, the numerals were presented in alphabetic format and had to be read aloud. Reading latencies were determined mostly by morphophonological factors in both modes. These results suggest that conceptual preparation, rather than response uncertainty, is responsible for the difference between naming and reading latencies.

Abstract

According to Levelt, Roelofs, and Meyer (1999) speakers generate the phonological and phonetic representations of successive syllables of a word in sequence and only begin to speak after having fully planned at least one complete phonological word. Therefore, speech onset latencies should be longer for long than for short words. We tested this prediction in four experiments in which Dutch participants named or categorized objects with monosyllabic or disyllabic names. Experiment 1 yielded a length effect on production latencies when objects with long and short names were tested in separate blocks, but not when they were mixed. Experiment 2 showed that the length effect was not due to a difference in the ease of object recognition. Experiment 3 replicated the results of Experiment 1 using a within-participants design. In Experiment 4, the long and short target words appeared in a phrasal context. In addition to the speech onset latencies, we obtained the viewing times for the target objects, which have been shown to depend on the time necessary to plan the form of the target names. We found word length effects for both dependent variables, but only when objects with short and long names were presented in separate blocks. We argue that in pure and mixed blocks speakers used different response deadlines, which they tried to meet by either generating the motor programs for one syllable or for all syllables of the word before speech onset. Computer simulations using WEAVER++ support this view.

Abstract

A comparison of Merge, a model of comprehension, and WEAVER, a model of production, raises five issues: (1) merging models of comprehension and production necessarily creates feedback; (2) neither model is a comprehensive account of word processing; (3) the models are incomplete in different ways; (4) the models differ in their handling of competition; (5) as opposed to WEAVER, Merge is a model of metalinguistic behavior.

Abstract

Subjects named pictures while hearing distractor words that shared word-initial or word-final segments with the picture names or were unrelated to the picture names. The relative timing of distractor and picture presentation was varied. Compared with unrelated distractors, both types of related distractors facilitated picture naming under certain timing conditions. Begin-related distractors facilitated the naming responses if the shared segments began 150 ms before, at, or 150 ms after picture onset. By contrast, end-related distractors only facilitated the responses if the shared segments began at or 150 ms after picture onset. The results suggest that the phonological encoding of the beginning of a word is initiated before the encoding of its end.

Abstract

The production and interpretation of pronouns involves the identification of a mental referent and, in connected speech or text, a discourse antecedent. One of the few overt signals of the relationship between a pronoun and its antecedent is agreement in features such as number and grammatical gender. To examine how speakers create these signals, two experiments tested conceptual, lexical. and morphophonological accounts of pronoun production in Dutch. The experiments employed sentence completion and continuation tasks with materials containing noun phrases that conflicted or agreed in grammatical gender. The noun phrases served as the antecedents for demonstrative pronouns tin Experiment 1) and relative pronouns tin Experiment 2) that required gender marking. Gender errors were used to assess the nature of the processes that established the link between pronouns and antecedents. There were more gender errors when candidate antecedents conflicted in grammatical gender, counter to the predictions of a pure conceptual hypothesis. Gender marking on candidate antecedents did not change the magnitude of this interference effect, counter to the predictions of an overt-morphology hypothesis. Mirroring previous findings about pronoun comprehension, the results suggest that speakers of gender-marking languages call on specific linguistic information about antecedents in order to select pronouns and that the information consists of specifications of grammatical gender associated with the lemmas of words.

Abstract

Eight experiments were carried out investigating whether different parts of a syllable must be phonologically encoded in a specific order or whether they can be encoded in any order. A speech production task was used in which the subjects in each test trial had to utter one out of three or five response words as quickly as possible. In the so-called homogeneous condition these words were related in form, while in the heterogeneous condition they were unrelated in form. For monosyllabic response words shorter reaction times were obtained in the homogeneous than in the heterogeneous condition when the words had the same onset, but not when they had the same rhyme. Similarly, for disyllabic response words, the reaction times were shorter in the homogeneous than in the heterogeneous condition when the words shared only the onset of the first syllable, but not when they shared only its rhyme. Furthermore, a stronger facilitatory effect was observed when the words had the entire first syllable in common than when they only shared the onset, or the onset and the nucleus, but not the coda of the first syllable. These results suggest that syllables are phonologically encoded in two ordered steps, the first of which is dedicated to the onset and the second to the rhyme.

Abstract

English, and a variety of Germanic languages, allow constructions such as the bottle floated into the cave , whereas languages such as Spanish, French, and Hindi are highly restricted in allowing manner of motion verbs to occur with path phrases. This typological observation has been accounted for in terms of the conflation of complex meaning in basic or derived verbs [Talmy, L., 1985. Lexicalization patterns: semantic structure in lexical forms. In: Shopen, T. (Ed.), Language Typology and Syntactic Description 3: Grammatical Categories and the Lexicon. Cambridge University Press, Cambridge, pp. 57–149; Levin, B., Rappaport-Hovav, M., 1995. Unaccusativity: At the Syntax–Lexical Semantics Interface. MIT Press, Cambridge, MA], or the presence of path “satellites” with special grammatical properties in the lexicon of languages such as English, which allow such phrasal combinations [cf. Talmy, L., 1985. Lexicalization patterns: semantic structure in lexical forms. In: Shopen, T. (Ed.), Language Typology and Syntactic Description 3: Grammatical Categories and the Lexicon. Cambridge University Press, Cambridge, pp. 57–149; Talmy, L., 1991. Path to realisation: via aspect and result. In: Proceedings of the Seventeenth Annual Meeting of the Berkeley Linguistics Society. Berkeley Linguistics Society, Berkeley, pp. 480–520]. I use data from Hindi to show that there is little empirical support for the claim that the constraint on the phrasal combination is correlated with differences in verb meaning or the presence of satellites in the lexicon of a language. However, proposals which eschew lexicalization accounts for more general aspectual constraints on the manner verb + path phrase combination in Spanish-type languages (Aske, J., 1989. Path Predicates in English and Spanish: A Closer look. In: Proceedings of the Fifteenth Annual Meeting of the Berkeley Linguistics Society. Berkeley Linguistics Society, Berkeley, pp. 1–14) cannot account for the full range of data in Hindi either. On the basis of these facts, I argue that an empirically adequate account can be formulated in terms of a general mapping constraint, formulated in terms of whether the lexical requirements of the verb strictly or weakly constrain its syntactic privileges of occurrence. In Hindi, path phrases can combine with manner of motion verbs only to the degree that they are compatible with the semantic profile of the verb. Path phrases in English, on the other hand, can extend the verb's “semantic profile” subject to certain constraints. I suggest that path phrases are licensed in English by the semantic requirements of the “construction” in which they appear rather than by the selectional requirements of the verb (Fillmore, C., Kay, P., O'Connor, M.C., 1988, Regularity and idiomaticity in grammatical constructions. Language 64, 501–538; Jackendoff, 1990, Semantic Structures. MIT Press, Cambridge, MA; Goldberg, 1995, Constructions: A Construction Grammar Approach to Argument Structure. University of Chicago Press, Chicago and London).

Abstract

This study demonstrates that listeners use lexical knowledge in perceptual learning of speech sounds. Dutch listeners first made lexical decisions on Dutch words and nonwords. The final fricative of 20 critical words had been replaced by an ambiguous sound, between [f] and [s]. One group of listeners heard ambiguous [f]-final words (e.g., [WI tlo?], from witlof, chicory) and unambiguous [s]-final words (e.g., naaldbos, pine forest). Another group heard the reverse (e.g., ambiguous [na:ldbo?], unambiguous witlof). Listeners who had heard [?] in [f]-final words were subsequently more likely to categorize ambiguous sounds on an [f]–[s] continuum as [f] than those who heard [?] in [s]-final words. Control conditions ruled out alternative explanations based on selective adaptation and contrast. Lexical information can thus be used to train categorization of speech. This use of lexical information differs from the on-line lexical feedback embodied in interactive models of speech perception. In contrast to on-line feedback, lexical feedback for learning is of benefit to spoken word recognition (e.g., in adapting to a newly encountered dialect).

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

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

Regions of the prefrontal cortex (PFC) are typically activated in many different cognitive functions. In most studies, the focus has been on the role of specific PFC regions in specific cognitive domains, but more recently similarities in PFC activations across cognitive domains have been stressed. Such similarities may suggest that a region mediates a common function across a variety of cognitive tasks. In this study, we compared the activation patterns associated with tests of working memory, semantic memory and episodic memory. The results converged on a general involvement of four regions across memory tests. These were located in left frontopolar cortex, left mid-ventrolateral PFC, left mid-dorsolateral PFC and dorsal anterior cingulate cortex. These findings provide evidence that some PFC regions are engaged during many different memory tests. The findings are discussed in relation to theories about the functional contribition of the PFC regions and the architecture of memory.

Abstract

Cognitive studies show that both younger and older adults can increase their memory performance after training in using a visuospatial mnemonic, although age-related memory deficits tend to be magnified rather than reduced after training. Little is known about the changes in functional brain activity that accompany training-induced memory enhancement, and whether age-related activity changes are associated with the size of training-related gains. Here, we demonstrate that younger adults show increased activity during memory encoding in occipito-parietal and frontal brain regions after learning the mnemonic. Older adults did not show increased frontal activity, and only those elderly persons who benefited from the mnemonic showed increased occipitoparietal activity. These findings suggest that age-related differences in cognitive reserve capacity may reflect both a frontal processing deficiency and a posterior production deficiency.

Abstract

Attention-deficit/hyperactivity disorder (ADHD [MIM 143465]) is a common, highly heritable neurobehavioral disorder of childhood onset, characterized by hyperactivity, impulsivity, and/or inattention. As part of an ongoing study of the genetic etiology of ADHD, we have performed a genomewide linkage scan in 204 nuclear families comprising 853 individuals and 270 affected sibling pairs (ASPs). Previously, we reported genomewide linkage analysis of a “first wave” of these families composed of 126 ASPs. A follow-up investigation of one region on 16p yielded significant linkage in an extended sample. The current study extends the original sample of 126 ASPs to 270 ASPs and provides linkage analyses of the entire sample, using polymorphic microsatellite markers that define an ∼10-cM map across the genome. Maximum LOD score (MLS) analysis identified suggestive linkage for 17p11 (MLS=2.98) and four nominal regions with MLS values >1.0, including 5p13, 6q14, 11q25, and 20q13. These data, taken together with the fine mapping on 16p13, suggest two regions as highly likely to harbor risk genes for ADHD: 16p13 and 17p11. Interestingly, both regions, as well as 5p13, have been highlighted in genomewide scans for autism.

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

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

We report three studies investigating children's and adults' comprehension of sentences containing the focus particle only. In Experiments 1 and 2, four groups of participants (6–7 years, 8–10 years, 11–12 years and adult) compared sentences with only in different syntactic positions against pictures that matched or mismatched events described by the sentence. Contrary to previous findings (Crain, S., Ni, W., & Conway, L. (1994). Learning, parsing and modularity. In C. Clifton, L. Frazier, & K. Rayner (Eds.), Perspectives on sentence processing. Hillsdale, NJ: Lawrence Erlbaum; Philip, W., & Lynch, E. (1999). Felicity, relevance, and acquisition of the grammar of every and only. In S. C. Howell, S. A. Fish, & T. Keith-Lucas (Eds.), Proceedings of the 24th annual Boston University conference on language development. Somerville, MA: Cascadilla Press) we found that young children predominantly made errors by failing to process contrast information rather than errors in which they failed to use syntactic information to restrict the scope of the particle. Experiment 3 replicated these findings with pre-schoolers.

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

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

In a within-subject design we investigated the levels-of-processing (LOP) effect using visual material in a behavioral and a corresponding PET study. In the behavioral study we characterize a generalized LOP effect, using pleasantness and graphical quality judgments in the encoding situation, with two types of visual material, figurative and nonfigurative line drawings. In the PET study we investigate the related pattern of brain activations along these two dimensions. The behavioral results indicate that instruction and material contribute independently to the level of recognition performance. Therefore the LOP effect appears to stem both from the relative relevance of the stimuli (encoding opportunity) and an altered processing of stimuli brought about by the explicit instruction (encoding mode). In the PET study, encoding of visual material under the pleasantness (deep) instruction yielded left lateralized frontoparietal and anterior temporal activations while surface-based perceptually oriented processing (shallow instruction) yielded right lateralized frontoparietal, posterior temporal, and occipitotemporal activations. The result that deep encoding was related to the left prefrontal cortex while shallow encoding was related to the right prefrontal cortex, holding the material constant, is not consistent with the HERA model. In addition, we suggest that the anterior medial superior frontal region is related to aspects of self-referential semantic processing and that the inferior parts of the anterior cingulate as well as the medial orbitofrontal cortex is related to affective processing, in this case pleasantness evaluation of the stimuli regardless of explicit semantic content. Finally, the left medial temporal lobe appears more actively engaged by elaborate meaning-based processing and the complex response pattern observed in different subregions of the MTL lends support to the suggestion that this region is functionally segregated.

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

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

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 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

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

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

A patient who already had Wernick's aphasia due to a left temporal lobe lesion suffered a severe deterioration specifically of auditory language comprehension, subsequent to right temporal lobe infarction. A detailed comparison of his new condition with his language status before the second stroke revealed that the newly acquired deficit was limited to tasks related to auditory input. Further investigations demonstrated a speech perceptual disorder, which we analysed as due to deficits both at the level of general auditory processes and at the level of phonetic analysis. We discuss some arguments related to hemisphere specialization of phonetic processing and to the disconnection explanation of word deafness that support the hypothesis of word deafness being generally caused by mixed deficits.

Abstract

The objectives of this article are to characterize the performance and to discuss the performance differences between literate and illiterate participants in a well-defined study population.We describe the participant-selection procedure used to investigate this population. Three groups with similar sociocultural backgrounds living in a relatively homogeneous fishing community in southern Portugal were characterized in terms of socioeconomic and sociocultural background variables and compared on a simple neuropsychological test battery; specifically, a literate group with more than 4 years of education (n = 9), a literate group with 4 years of education (n = 26), and an illiterate group (n = 31) were included in this study.We compare and discuss our results with other similar studies on the effects of literacy and illiteracy. The results indicate that naming and identification of real objects, verbal fluency using ecologically relevant semantic criteria, verbal memory, and orientation are not affected by literacy or level of formal education. In contrast, verbal working memory assessed with digit span, verbal abstraction, long-term semantic memory, and calculation (i.e., multiplication) are significantly affected by the level of literacy. We indicate that it is possible, with proper participant-selection procedures, to exclude general cognitive impairment and to control important sociocultural factors that potentially could introduce bias when studying the specific effects of literacy and level of formal education on cognitive brain function.

Abstract

Is there a relation between socioeconomic factors and aphasia severity and recovery? Connor, Obler, Tocco, Fitzpatrick, and Albert (2001) describe correlations between the educational level and socioeconomic status of aphasic subjects with aphasia severity and subsequent recovery. As stated in the introduction by Connor et al. (2001), studies of the influence of educational level and literacy (or illiteracy) on aphasia severity have yielded conflicting results, while no significant link between socioeconomic status and aphasia severity and recovery has been established. In this brief note, we will comment on their findings and conclusions, beginning first with a brief review of literacy and aphasia research, and complexities encountered in these fields of investigation. This serves as a general background to our specific comments on Connor et al. (2001), which will be focusing on methodological issues and the importance of taking normative values in consideration when subjects with different socio-cultural or socio-economic backgrounds are assessed.

Abstract

Four form-preparation experiments investigated whether aspects of phonological encoding processes and representations are shared between languages in bilingual speakers. The participants were Dutch--English bilinguals. Experiment 1 showed that the basic rightward incrementality revealed in studies for the first language is also observed for second-language words. In Experiments 2 and 3, speakers were given words to produce that did or did not share onset segments, and that came or did not come from different languages. It was found that when onsets were shared among the response words, those onsets were prepared, even when the words came from different languages. Experiment 4 showed that preparation requires prior knowledge of the segments and that knowledge about their phonological features yields no effect. These results suggest that both first- and second-language words are phonologically planned through the same serial order mechanism and that the representations of segments common to the languages are shared.

Abstract

This article presents a new account of the color-word Stroop phenomenon ( J. R. Stroop, 1935) based on an implemented model of word production, WEAVER++ ( W. J. M. Levelt, A. Roelofs, & A. S. Meyer, 1999b; A. Roelofs, 1992, 1997c). Stroop effects are claimed to arise from processing interactions within the language-production architecture and explicit goal-referenced control. WEAVER++ successfully simulates 16 classic data sets, mostly taken from the review by C. M. MacLeod (1991), including incongruency, congruency, reverse-Stroop, response-set, semantic-gradient, time-course, stimulus, spatial, multiple-task, manual, bilingual, training, age, and pathological effects. Three new experiments tested the account against alternative explanations. It is shown that WEAVER++ offers a more satisfactory account of the data than other models.

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

Accounts that specify semantic and/or syntactic complexity as the primary determinant of the order in which children acquire particular words or grammatical constructions have been highly influential in the literature on question acquisition. One explanation of wh-question acquisition in particular suggests that the order in which English speaking children acquire wh-questions is determined by two interlocking linguistic factors; the syntactic function of the wh-word that heads the question and the semantic generality (or ‘lightness’) of the main verb (Bloom, Merkin & Wootten, 1982; Bloom, 1991). Another more recent view, however, is that acquisition is influenced by the relative frequency with which children hear particular wh-words and verbs in their input (e.g. Rowland & Pine, 2000). In the present study over 300 hours of naturalistic data from twelve two- to three-year-old children and their mothers were analysed in order to assess the relative contribution of complexity and input frequency to wh-question acquisition. The analyses revealed, first, that the acquisition order of wh-questions could be predicted successfully from the frequency with which particular wh-words and verbs occurred in the children's input and, second, that syntactic and semantic complexity did not reliably predict acquisition once input frequency was taken into account. These results suggest that the relationship between acquisition and complexity may be a by-product of the high correlation between complexity and the frequency with which mothers use particular wh-words and verbs. We interpret the results in terms of a constructivist view of language acquisition.

Abstract

Van Valin (Journal of Child Language29, 2002, 161–75) presents a critique of Rowland & Pine (Journal of Child Language27, 2000, 157–81) and argues that the wh-question data from Adam (in Brown, A first language, Cambridge, MA, 1973) cannot be explained in terms of input frequencies as we suggest. Instead, he suggests that the data can be more successfully accounted for in terms of Role and Reference Grammar. In this note we re-examine the pattern of inversion and uninversion in Adam's wh-questions and argue that the RRG explanation cannot account for some of the developmental facts it was designed to explain.

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

In this article, we present the spatial logistics task (SLOT) platform for investigating multimodal communication between 2 human participants. Presented are the SLOT communication task and the software and hardware that has been developed to run SLOT experiments and record the participants’ multimodal behavior. SLOT offers a high level of flexibility in varying the context of the communication and is particularly useful in studies of the relationship between pen gestures and speech. We illustrate the use of the SLOT platform by discussing the results of some early experiments. The first is an experiment on negotiation with a one-way mirror between the participants, and the second is an exploratory study of automatic recognition of spontaneous pen gestures. The results of these studies demonstrate the usefulness of the SLOT platform for conducting multimodal communication research in both human– human and human–computer interactions.

Abstract

Participants' eye movements were monitored as they heard sentences and saw four pictured objects on a computer screen. Participants were instructed to click on the object mentioned in the sentence. There were more transitory fixations to pictures representing monosyllabic words (e.g. ham) when the first syllable of the target word (e.g. hamster) had been replaced by a recording of the monosyllabic word than when it came from a different recording of the target word. This demonstrates that a phonemically identical sequence can contain cues that modulate its lexical interpretation. This effect was governed by the duration of the sequence, rather than by its origin (i.e. which type of word it came from). The longer the sequence, the more monosyllabic-word interpretations it generated. We argue that cues to lexical-embedding disambiguation, such as segmental lengthening, result from the realization of a prosodic boundary that often but not always follows monosyllabic words, and that lexical candidates whose word boundaries are aligned with prosodic boundaries are favored in the word-recognition process.

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

This letter evaluates potential benefits of combining human speech recognition ~HSR! and automatic speech recognition by building a joint model of an automatic phone recognizer ~APR! and a computational model of HSR, viz., Shortlist @Norris, Cognition 52, 189–234 ~1994!#. Experiments based on ‘‘real-life’’ speech highlight critical limitations posed by some of the simplifying assumptions made in models of human speech recognition. These limitations could be overcome by avoiding hard phone decisions at the output side of the APR, and by using a match between the input and the internal lexicon that flexibly copes with deviations from canonical phonemic representations.

Abstract

In this paper, we present an automatic speech recognition (ASR) system based on the combination of an automatic phone recogniser and a computational model of human speech recognition – SpeM – that is capable of computing ‘word activations’ during the recognition process, in addition to doing normal speech recognition, a task in which conventional ASR architectures only provide output after the end of an utterance. We explain the notion of word activation and show that it can be used for ‘early recognition’, i.e. recognising a word before the end of the word is available. Our ASR system was tested on 992 continuous speech utterances, each containing at least one target word: a city name of at least two syllables. The results show that early recognition was obtained for 72.8% of the target words that were recognised correctly. Also, it is shown that word activation can be used as an effective confidence measure.

Abstract

During language production and comprehension, information about a word's syntactic properties is sometimes needed. While the decision about the grammatical gender of a word requires access to syntactic knowledge, it has also been hypothesized that semantic (i.e., biological gender) or phonological information (i.e., sound regularities) may influence this decision. Event-related potentials (ERPs) were measured while native speakers of German processed written words that were or were not semantically and/or phonologically marked for gender. Behavioral and ERP results showed that participants were faster in making a gender decision when words were semantically and/or phonologically gender marked than when this was not the case, although the phonological effects were less clear. In conclusion, our data provide evidence that even though participants performed a grammatical gender decision, this task can be influenced by semantic and phonological factors.

Abstract

This study investigated the time course of phonological encoding during speech production planning. Previous research has shown that conceptual/semantic information precedes syntactic information in the planning of speech production and that syntactic information is available earlier than phonological information. Here, we studied the relative time courses of the two different processes within phonological encoding, i.e. metrical encoding and syllabification. According to one prominent theory of language production, metrical encoding involves the retrieval of the stress pattern of a word, while syllabification is carried out to construct the syllabic structure of a word. However, the relative timing of these two processes is underspecified in the theory. We employed an implicit picture naming task and recorded event-related brain potentials to obtain fine-grained temporal information about metrical encoding and syllabification. Results revealed that both tasks generated effects that fall within the time window of phonological encoding. However, there was no timing difference between the two effects, suggesting that they occur approximately at the same time.

Abstract

In this study, we investigated grammatical feature selection during noun phrase production in German and Dutch. More specifically, we studied the conditions under which different grammatical genders select either the same or different determiners or suffixes. Pictures of one or two objects paired with a gender-congruent or a gender-incongruent distractor word were presented. Participants named the pictures using a singular or plural noun phrase with the appropriate determiner and/or adjective in German or Dutch. Significant effects of gender congruency were only obtained in the singular condition where the selection of determiners is governed by the target’s gender, but not in the plural condition where the determiner is identical for all genders. When different suffixes were to be selected in the gender-incongruent condition, no gender congruency effect was obtained. The results suggest that the so-called gender congruency effect is really a determiner congruency effect. The overall pattern of results is interpreted as indicating that grammatical feature selection is an automatic consequence of lexical node selection and therefore not subject to interference from other grammatical features. This implies that lexical node and grammatical feature selection operate with distinct principles.

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

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

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

Aboriginal languages threatened by speakers poor economic and social conditions; some may survive through support for community development, language maintenance, bilingual education and training of Aboriginal teachers and linguists, and nonAboriginal teachers of Aboriginal and Islander students.

Abstract

We present the results of a large-scale study on speech perception, assessing the number and type of perceptual hypotheses which listeners entertain about possible phoneme sequences in their language. Dutch listeners were asked to identify gated fragments of all 1179 diphones of Dutch, providing a total of 488 520 phoneme categorizations. The results manifest orderly uptake of acoustic information in the signal. Differences across phonemes in the rate at which fully correct recognition was achieved arose as a result of whether or not potential confusions could occur with other phonemes of the language ~long with short vowels, affricates with their initial components, etc.!. These data can be used to improve models of how acoustic phonetic information is mapped onto the mental lexicon during speech comprehension.

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

Finnish vowel harmony rules require that if the vowel in the first syllable of a word belongs to one of two vowel sets, then all subsequent vowels in that word must belong either to the same set or to a neutral set. A harmony mismatch between two syllables containing vowels from the opposing sets thus signals a likely word boundary. We report five experiments showing that Finnish listeners can exploit this information in an on-line speech segmentation task. Listeners found it easier to detect words likehymyat the end of the nonsense stringpuhymy(where there is a harmony mismatch between the first two syllables) than in the stringpyhymy(where there is no mismatch). There was no such effect, however, when the target words appeared at the beginning of the nonsense string (e.g.,hymypuvshymypy). Stronger harmony effects were found for targets containing front harmony vowels (e.g.,hymy) than for targets containing back harmony vowels (e.g.,paloinkypaloandkupalo). The same pattern of results appeared whether target position within the string was predictable or unpredictable. Harmony mismatch thus appears to provide a useful segmentation cue for the detection of word onsets in Finnish speech.

Abstract

Spoken language comprehension requires rapid integration of information from multiple linguistic sources. In the present study we addressed the temporal aspects of this integration process by focusing on the time course of the selection of the appropriate meaning of lexical ambiguities (“bank”) in sentence contexts. Successful selection of the contextually appropriate meaning of the ambiguous word is dependent upon the rapid binding of the contextual information in the sentence to the appropriate meaning of the ambiguity. We used the N400 to identify the time course of this binding process. The N400 was measured to target words that followed three types of context sentences. In the concordant context, the sentence biased the meaning of the sentence-final ambiguous word so that it was related to the target. In the discordant context, the sentence context biased the meaning so that it was not related to the target. In the unrelated control condition, the sentences ended in an unambiguous noun that was unrelated to the target. Half of the concordant sentences biased the dominant meaning, and the other half biased the subordinate meaning of the sentence-final ambiguous words. The ISI between onset of the target word and offset of the sentence-final word of the context sentence was 100 ms in one version of the experiment, and 1250 ms in the second version. We found that (i) the lexically dominant meaning is always partly activated, independent of context, (ii) initially both dominant and subordinate meaning are (partly) activated, which suggests that contextual and lexical factors both contribute to sentence interpretation without context completely overriding lexical information, and (iii) strong lexical influences remain present for a relatively long period of time.