Publications

Abstract

In general, language comprehension is surprisingly reliable. Listeners very rapidly extract meaning from the unfolding speech signal, on a word-by-word basis, and usually successfully. Research on ‘semantic illusions’ however suggests that under certain conditions, people fail to notice that the linguistic input simply doesn't make sense. In the current event-related brain potentials (ERP) study, we examined whether listeners would, under such conditions, spontaneously detect an anomaly in which a human character central to the story at hand (e.g., “a tourist”) was suddenly replaced by an inanimate object (e.g., “a suitcase”). Because this replacement introduced a very powerful coherence break, we expected listeners to immediately notice the anomaly and generate the standard ERP effect associated with incoherent language, the N400 effect. However, instead of the standard N400 effect, anomalous words elicited a positive ERP effect from about 500–600 ms onwards. The absence of an N400 effect suggests that subjects did not immediately notice the anomaly, and that for a few hundred milliseconds the comprehension system has converged on an apparently coherent but factually incorrect interpretation. The presence of the later ERP effect indicates that subjects were processing for comprehension and did ultimately detect the anomaly. Therefore, we take the absence of a regular N400 effect as the online manifestation of a temporary semantic illusion. Our results also show that even attentive listeners sometimes fail to notice a radical change in the nature of a story character, and therefore suggest a case of short-lived ‘semantic change deafness’ in language comprehension.

Abstract

What are the relations between linguistic encoding and gestural representations of events during online speaking? The few studies that have been conducted on this topic have yielded somewhat incompatible results with regard to whether and how gestural representations of events change with differences in the preferred semantic and syntactic encoding possibilities of languages. Here we provide large scale semantic, syntactic and temporal analyses of speech- gesture pairs that depict 10 different motion events from 20 Turkish and 20 English speakers. We find that the gestural representations of the same events differ across languages when they are encoded by different syntactic frames (i.e., verb-framed or satellite-framed). However, where there are similarities across languages, such as omission of a certain element of the event in the linguistic encoding, gestural representations also look similar and omit the same content. The results are discussed in terms of what gestures reveal about the influence of language specific encoding on on-line thinking patterns and the underlying interactions between speech and gesture during the speaking process.

Abstract

Recent FMRI studies indicate that language related brain regions are engaged in artificial grammar (AG) processing. In the present study we investigate the Reber grammar by means of formal analysis and network simulations. We outline a new method for describing the network dynamics and propose an approach to grammar extraction based on the state-space dynamics of the network. We conclude that statistical frequency-based and rule-based acquisition procedures can be viewed as complementary perspectives on grammar learning, and more generally, that classical cognitive models can be viewed as a special case of a dynamical systems perspective on information processing

Abstract

We present two simple arguments for the potential relevance of a neurobiological analogue of the finite-state architecture. The first assumes the classical cognitive framework, is wellknown, and is based on the assumption that the brain is finite with respect to its memory organization. The second is formulated within a general dynamical systems framework and is based on the assumption that the brain sustains some level of noise and/or does not utilize infinite precision processing. We briefly review the classical cognitive framework based on Church–Turing computability and non-classical approaches based on analog processing in dynamical systems. We conclude that the dynamical neurobiological analogue of the finitestate architecture appears to be relevant, at least at an implementational level, for cognitive brain systems

Abstract

In The Netherlands, grammar teaching is an especially important subject in the curriculum of children aged 10-15 for several reasons. However, in spite of all attention and time invested, the results are poor. This article describes the problems and our attempt to overcome them by developing an intelligent computational instructional environment consisting of: a linguistic expert system, containing a module representing grammar and spelling rules and a number of modules to manipulate these rules; a didactic module; and a student interface with special facilities for grammar and spelling. Three prototypes of the functionality are discussed: BOUWSTEEN and COGO, which are programs for constructing and analyzing Dutch sentences; and TDTDT, a program for the conjugation of Dutch verbs.

Abstract

One of the most influential recent accounts of pronoun case-marking errors in young children's speech is Schütze & Wexler's (1996) Agreement/Tense Omission Model (ATOM). The ATOM predicts that the rate of agreeing verbs with non-nominative subjects will be so low that such errors can be reasonably disregarded as noise in the data. The present study tests this prediction on data from 12 children between the ages of 1;8.22 and 3;0.10. This is done, first, by identifying children who produced a reasonably large number of non-nominative 3psg subjects; second, by estimating the expected rate of agreeing verbs with masculine and feminine non-nominative subjects in these children's speech; and, third, by examining the actual rate at which agreeing verb forms occurred with non-nominative subjects in those areas of the data in which the expected error rate was significantly greater than 10%. The results show, first, that only three of the children produced enough non-nominative subjects to allow a reasonable test of the ATOM to be made; second, that for all three of these children, the only area of the data in which the expected frequency of agreeing verbs with non-nominative subjects was significantly greater than 10% was their use of feminine case-marked subjects; and third, that for all three of these children, the rate of agreeing verbs with non-nominative feminine subjects was over 30%. These results raise serious doubts about the claim that children's use of non-nominative subjects can be explained in terms of AGR optionality, and suggest the need for a model of pronoun case-marking error that can explain why some children produce agreeing verb forms with non-nominative subjects as often as they do.

Abstract

This study investigates the relationship between word repetition, predictability from neighbouring words, and articulatory reduction in Dutch. For the seven most frequent words ending in the adjectival suffix -lijk, 40 occurrences were randomly selected from a large database of face-to-face conversations. Analysis of the selected tokens showed that the degree of articulatory reduction (as measured by duration and number of realized segments) was affected by repetition, predictability from the previous word and predictability from the following word. Interestingly, not all of these effects were significant across morphemes and target words. Repetition effects were limited to suffixes, while effects of predictability from the previous word were restricted to the stems of two of the seven target words. Predictability from the following word affected the stems of all target words equally, but not all suffixes. The implications of these findings for models of speech production are discussed.

Abstract

This study investigates the effects of lexical frequency on the durational reduction of morphologically complex words in spoken Dutch. The hypothesis that high-frequency words are more reduced than low-frequency words was tested by comparing the durations of affixes occurring in different carrier words. Four Dutch affixes were investigated, each occurring in a large number of words with different frequencies. The materials came from a large database of face-to-face conversations. For each word containing a target affix, one token was randomly selected for acoustic analysis. Measurements were made of the duration of the affix as a whole and the durations of the individual segments in the affix. For three of the four affixes, a higher frequency of the carrier word led to shorter realizations of the affix as a whole, individual segments in the affix, or both. Other relevant factors were the sex and age of the speaker, segmental context, and speech rate. To accommodate for these findings, models of speech production should allow word frequency to affect the acoustic realizations of lower-level units, such as individual speech sounds occurring in affixes.

Abstract

It has recently been reported that words containing a multiletter grapheme are processed slower than are words composed of single-letter graphemes (Rastle & Coltheart, 1998; Rey, Jacobs, Schmidt-Weigand, & Ziegler, 1998). In the present study, using a perceptual identification task, we found in Experiment 1 that this graphemic complexity effect can be observed while controlling for multiple print-to-sound associations, indexed by regularity or consistency. In Experiment 2, we obtained cumulative effects of graphemic complexity and regularity. These effects were replicated in Experiment 3 in a naming task. Overall, these results indicate that graphemic complexity and multiple print-to-sound associations effects are independent and should be accounted for in different ways by models of written word processing.

Abstract

Four experiments examined crossmodal versions of the Stroop task in order (1) to look for Stroop asymmetries in color naming, spoken-word naming, and written-word naming and to evaluate the time course of these asymmetries, and (2) to compare these findings to current models of the Stroop effect. Participants named color patches while ignoring spoken color words presented with an onset varying from 300 msec before to 300 msec after the onset of the color (Experiment 1), or they named the spoken words and ignored the colors (Experiment 2). A secondary visual detection task assured that the participants looked at the colors in both tasks. Spoken color words yielded Stroop effects in color naming, but colors did not yield an effect in spoken-word naming at any stimulus onset asynchrony. This asymmetry in effects was obtained with equivalent color- and spoken-word-naming latencies. Written color words yielded a Stroop effect in naming spoken words (Experiment 3), and spoken color words yielded an effect in naming written words (Experiment 4). These results were interpreted as most consistent with an architectural account of the color-word Stroop asymmetry, in contrast with discriminability and pathway strength accounts.

Abstract

Many current generativist theorists suggest that young children possess the grammatical principles of inversion required for question formation but make errors because they find it difficult to learn language-specific rules about how inversion applies. The present study analyzed longitudinal spontaneous sampled data from twelve 2–3-year-old English speaking children and the intensive diary data of 1 child (age 2;7 [years;months] to 2;11) in order to test some of these theories. The results indicated significantly different rates of error use across different auxiliaries. In particular, error rates differed across 2 forms of the same auxiliary subtype (e.g., auxiliary is vs. are), and auxiliary DO and modal auxiliaries attracted significantly higher rates of errors of inversion than other auxiliaries. The authors concluded that current generativist theories might have problems explaining the patterning of errors seen in children's questions, which might be more consistent with a constructivist account of development. However, constructivists need to devise more precise predictions in order to fully explain the acquisition of questions.

Abstract

The research presented in this dissertation examined the influence of prosodically-conditioned detail on the recognition of spoken words. The main finding is that subphonemic information in the speech signal that is conditioned by constituent-level prosodic structure can affect lexical processing systematically. It was shown that such information, as indicated by and estimated from the lengthening of speech sounds in the vicinity of prosodic boundaries, can help listeners to distinguish onset-embedded words (e.g. 'ham') from longer words that have this word embedded at their onset (e.g. 'hamster'). Furthermore, it was shown that variation in the realization of a spoken word that is associated with its position in the prosodic structure of an utterance can effect lexical processing. The pattern of competitor activation associated with the recognition of a monosyllabic spoken word in utterance-final position, where the realization of the word is strongly affected by the utterance boundary, is different from that associated with the recognition of the same word in utterance-medial position, where the realization of the word is less strongly affected by the following prosodic-word boundary. Taken together, the findings attest to the extraordinary sensitivity of the spoken-word recogntion system by demonstrating the relevance for lexical processing of very fine-grained phonetic detail conditioned by prosodic structure.

Abstract

A series of experiment tested Ekman’s (1992) hypothesis that there are a set of positive basic emotions that are expressed using vocal para-linguistic sounds, e.g. laughter and cheers. The proposed categories investigated were amusement, contentment, pleasure, relief and triumph. Behavioural testing using a forced-choice task indicated that participants were able to reliably recognize vocal expressions of the proposed emotions. A cross-cultural study in the preliterate Himba culture in Namibia confirmed that these categories are also recognized across cultures. A recognition test of acoustically manipulated emotional vocalizations established that the recognition of different emotions utilizes different vocal cues, and that these in turn differ from the cues used when comprehending speech. In a study using fMRI we found that relative to a signal correlated noise baseline, the paralinguistic expressions of emotion activated bilateral superior temporal gyri and sulci, lateral and anterior to primary auditory cortex, which is consistent with the processing of non linguistic vocal cues in the auditory ‘what’ pathway. Notably amusement was associated with greater activation extending into both temporal poles and amygdale and insular cortex. Overall, these results support the claim that ‘happiness’ can be fractionated into amusement, pleasure, relief and triumph.

Abstract

This paper addresses the issue of large-vocabulary recognition in a specific word class. We propose a two-pass strategy in which only major cities are explicitly represented in the first stage lexicon. An unknown word model encoded as a phone loop is used to detect OOV city names (referred to as rare city names). After which SpeM, a tool that can extract words and word-initial cohorts from phone graphs on the basis of a large fallback lexicon, provides an N-best list of promising city names on the basis of the phone sequences generated in the first stage. This N-best list is then inserted into the second stage lexicon for a subsequent recognition pass. Experiments were conducted on a set of spontaneous telephone-quality utterances each containing one rare city name. We tested the size of the N-best list and three types of language models (LMs). The experiments showed that SpeM was able to include nearly 85% of the correct city names into an N-best list of 3000 city names when a unigram LM, which also boosted the unigram scores of a city name in a given state, was used.

Abstract

Although researchers studying human speech recognition (HSR) and automatic speech recognition (ASR) share a common interest in how information processing systems (human or machine) recognize spoken language, there is little communication between the two disciplines. We suggest that this lack of communication follows largely from the fact that research in these related fields has focused on the mechanics of how speech can be recognized. In Marr's (1982) terms, emphasis has been on the algorithmic and implementational levels rather than on the computational level. In this article, we provide a computational-level analysis of the task of speech recognition, which reveals the close parallels between research concerned with HSR and ASR. We illustrate this relation by presenting a new computational model of human spoken-word recognition, built using techniques from the field of ASR that, in contrast to current existing models of HSR, recognizes words from real speech input.

Abstract

RU Radboud Universiteit Nijmegen, 16 september 2005

Abstract

In this paper, we illustrate the close parallels between the research fields of human speech recognition (HSR) and automatic speech recognition (ASR) using a computational model of human word recognition, SpeM, which was built using techniques from ASR. We show that ASR has proven to be useful for improving models of HSR by relieving them of some of their shortcomings. However, in order to build an integrated computational model of all aspects of HSR, a lot of issues remain to be resolved. In this process, ASR algorithms and techniques definitely can play an important role.

Abstract

Neuronal groups can interact with each other even if they are widely separated. One group might modulate its firing rate or its internal oscillatory synchronization to influence another group. We propose that coherence between two neuronal groups is a mechanism of efficient interaction, because it renders mutual input optimally timed and thereby maximally effective. Modulations of subjects' readiness to respond in a simple reaction-time task were closely correlated with the strength of gamma-band (40 to 70 hertz) coherence between motor cortex and spinal cord neurons. This coherence may contribute to an effective corticospinal interaction and shortened reaction times.

Abstract

According to certain theories of language production, lexical access to a content word consists of two independent and serially ordered stages. In the first, semantically driven stage, so-called lemmas are retrieved, i.e., lexical items that are specified with respect to syntactic and semantic properties, but not with respect to phonological characteristics. In the second stage, the corresponding wordforms, the so-called lexemes, are retrieved. This implies that the access to a content word involves an early stage of exclusively semantic activation and a later stage of exclusively phonological activation. This seriality assumption was tested experimentally, using a picture-word interference paradigm in which the interfering words were presented auditorily. The results show an interference effect of semantically related words on picture naming latencies at an early SOA (− 150 ms), and a facilitatory effect of phonologically related words at later SOAs (0 ms, + 150 ms). On the basis of these results it can be concluded that there is indeed a stage of lexical access to a content word where only its meaning is activated, followed by a stage where only its form is activated. These findings can be seen as empirical support for a two-stage model of lexical access, or, alternatively, as putting constraints on the parameters in a network model of lexical access, such as the model proposed by Dell and Reich.

Abstract

Miraña, an endangered Witotoan language spoken in the Colombian Amazon region, has an inventory of over 60 noun class markers, most of which denote the shape of nominal referents. Class markers in this language are ubiquitous in their uses for derivational purposes in nouns and for agreement marking in virtually all other nominal expressions, such as pronouns, numerals, demonstratives, and relative clauses, as well as in verbs. This study provides a comprehensive analysis of this system by giving equal attention to its morphosyntactic, semantic, and discourse-pragmatic properties. The particular properties of this system raise issues in a number of ongoing theoretical discussions, in particular the typology of systems of nominal classification and the typology of reference tracking.

Abstract

In his paper ‘On Horn's dilemma: presupposition and negation’ Burton-Roberts (1989a) presents an ambitious programme, formulated right at the outset. He seeks to establish three points: (i) Under the ‘standard logical definition of presupposition’ a pre-suppositional semantics is INCOMPATIBLE with a SEMANTICALLY AMBIGUOUS NEGATION operator (SAN), on pain of the theory being rendered ‘empirically empty and theoretically trivial’,. (ii) From this it follows that the one unambiguous negation is presupposition preserving. Cases that have been identified as presupposition-cancelling negation should be re-analysed as ‘instances of a pragmatic phenomenon’, not unlike what has been proposed in Horn (1985), that is as METALINGUISTIC NEGATION (MN). (iii) This pragmatic analysis of MN ‘itself implies a presuppositional semantics’, that is to say ‘a presuppositional theory of truth-value gaps’.

Abstract

It is the purpose of the present paper to highlight the figure of Eubulides, a relatively unknown Greek philosopher who lived ±405–330 BC and taught at Megara, not far from Athens. He is mainly known for his four paradoxes (the Liar, the Sorites, the Electra, and the Horns), and for the mutual animosity between him and his younger contemporary Aristotle. The Megarian school of philosophy was one of the main sources of the great Stoic tradition in ancient philosophy. What has never been made explicit in the literature is the importance of the four paradoxes for the study of meaning in natural language: they summarize the whole research programme of 20th century formal or formally oriented semantics, including the problems of vague predicates (Sorites), intensional contexts (Electra), and presuppositions (Horns). One might say that modern formal or formally oriented semantics is essentially an attempt at finding linguistically tenable answers to problems arising in the context of Aristotelian thought. It is a surprising and highly significant fact that a contemporary of Aristotle already spotted the main weaknesses of the Aristotelian paradigm.

Abstract

Dissociations in the ability to produce words of different grammatical categories are well established in neuropsychology but have not been corroborated fully with evidence from brain imaging. Here we report on a PET study designed to reveal the anatomical correlates of grammatical processes involving nouns and verbs. German-speaking subjects were asked to produce either plural and singular nouns, or first-person plural and singular verbs. Verbs, relative to nouns, activated a left frontal cortical network, while the opposite contrast (nouns–verbs) showed greater activation in temporal regions bilaterally. Similar patterns emerged when subjects performed the task with pseudowords used as nouns or as verbs. These results converge with findings from lesion studies and suggest that grammatical category is an important dimension of organization for knowledge of language in the brain.

Abstract

Positron emission tomography was used to investigate two competing hypotheses about the role of the left inferior frontal gyrus (IFG) in word generation. One proposes a domain-specific organization, with neural activation dependent on the type of information being processed, i.e., surface sound structure or semantic. The other proposes a process-specific organization, with activation dependent on processing demands, such as the amount of selection needed to decide between competing lexical alternatives. In a novel word retrieval task, word reconstruction (WR), subjects generated real words from heard non-words by the substitution of either a vowel or consonant. Both types of lexical retrieval, informed by sound structure alone, produced activation within anterior and posterior left IFG regions. Within these regions there was greater activity for consonant WR, which is more difficult and imposes greater processing demands. These results support a process-specific organization of the anterior left IFG.

Abstract

This article examines pediatrician-parent interaction in the context of acute pediatric encounters for children with upper respiratory infections. Parents and physicians orient to treatment recommendations as normatively requiring parent acceptance for physicians to close the activity. Through acceptance, withholding of acceptance, or active resistance, parents have resources with which to negotiate for a treatment outcome that is in line with their own wants. This article offers evidence that even in acute care, shared decision making not only occurs but, through normative constraints, is mandated for parents and physicians to reach accord in the treatment decision.

Abstract

In this article I examine one practice speakers have for confirming when confirmation was not otherwise relevant. The practice involves a speaker repeating an assertion previously made by another speaker in modified form with stress on the copula/auxiliary. I argue that these modified repeats work to undermine the first speaker's default ownership and rights over the claim and instead assert the primacy of the second speaker's rights to make the statement. Two types of modified repeats are identified: partial and full. Although both involve competing for primacy of the claim, they occur in distinct sequential environments: The former are generally positioned after a first claim was epistemically downgraded, whereas the latter are positioned following initial claims that were offered straightforwardly, without downgrading.

Abstract

That human social interaction involves the intertwined cooperation of different modalities is uncontroversial. Researchers in several allied fields have, however, only recently begun to document the precise ways in which talk, gesture, gaze, and aspects of the material surround are brought together to form coherent courses of action. The papers in this volume are attempts to develop this line of inquiry. Although the authors draw on a range of analytic, theoretical, and methodological traditions (conversation analysis, ethnography, distributed cognition, and workplace studies), all are concerned to explore and illuminate the inherently multimodal character of social interaction. Recent studies, including those collected in this volume, suggest that different modalities work together not only to elaborate the semantic content of talk but also to constitute coherent courses of action. In this introduction we present evidence for this position. We begin by reviewing some select literature focusing primarily on communicative functions and interactive organizations of specific modalities before turning to consider the integration of distinct modalities in interaction.

Abstract

This study draws on a database of 570 community-based acute pediatric encounters in the USA and uses conversation analysis as a methodology to identify two formats physicians use to recommend non-antibiotic treatment in acute pediatric care (using a subset of 309 cases): recommendations for particular treatment (e.g., “I’m gonna give her some cough medicine.”) and recommendations against particular treatment (e.g., “She doesn’t need any antibiotics.”). The findings are that the presentation of a specific affirmative recommendation for treatment is less likely to engender parent resistance to a non-antibiotic treatment recommendation than a recommendation against particular treatment even if the physician later offers a recommendation for particular treatment. It is suggested that physicians who provide a specific positive treatment recommendation followed by a negative recommendation are most likely to attain parent alignment and acceptance when recommending a non-antibiotic treatment for a viral upper respiratory illness.

Abstract

Thirty-eight 3-, 6-, and 9-month-old infants interacted in a face to face situation with a female stranger who disrupted the on-going interaction with 30 s Happy and Neutral still face episodes. Three- and 6-month-olds manifested a robust still face response for gazing and smiling. For smiling, 9-month-olds manifested a floor effect such that no still face effect could be shown. For gazing, 9-month-olds' still face response was modulated by the context of interaction such that it was less pronounced if a happy still face was presented first. The findings point to a developmental transition by the end of the first year, whereby infants' still face response becomes increasingly influenced by the context of social interaction. (C) 2004 Published by Elsevier Inc. [References: 35]

Abstract

Infants parse speech into word-sized units according to biases that develop in the first year. One bias, present before the age of 7 months, is to cluster syllables that tend to co-occur. The present computational research demonstrates that this statistical clustering bias could lead to the extraction of speech sequences that are actual words, rather than missegmentations. In English and Dutch, these word-forms exhibit the strong–weak (trochaic) pattern that guides lexical segmentation after 8 months, suggesting that the trochaic parsing bias is learned as a generalization from statistically extracted bisyllables, and not via attention to short utterances or to high-frequency bisyllables. Extracted word-forms come from various syntactic classes, and exhibit distributional characteristics enabling rudimentary sorting of words into syntactic categories. The results highlight the importance of infants’ first year in language learning: though they may know the meanings of very few words, infants are well on their way to building a vocabulary.

Abstract

During the first year of life, infants' perception of speech becomes tuned to the phonology of the native language, as revealed in laboratory discrimination and categorization tasks using syllable stimuli. However, the implications of these results for the development of the early vocabulary remain controversial, with some results suggesting that infants retain only vague, sketchy phonological representations of words. Five experiments using a preferential listening procedure tested Dutch 11-month-olds' responses to word, nonword and mispronounced-word stimuli. Infants listened longer to words than nonwords, but did not exhibit this response when words were mispronounced at onset or at offset. In addition, infants preferred correct pronunciations to onset mispronunciations. The results suggest that infants' encoding of familiar words includes substantial phonological detail.

Abstract

The roles which word class (open/closed) and sentential stress play in the sentence comprehension processes of both agrammatic (Broca's) aphasics and normal listeners were examined with a word monitoring task. Overall, normal listeners responded more quickly to stressed than to unstressed items, but showed no effect of word class. Aphasics also responded more quickly to stressed than to unstressed materials, but, unlike the normals, responded faster to open than to closed class words regardless of their stress. The results are interpreted as support for the theory that Broca's aphasics lack the functional underlying open/closed class word distinction used in word recognition by normal listeners.

Abstract

Two experiments examined the nature of access, storage, and comprehension of idiomatic phrases. In both studies a Phrase Classification Task was utilized. In this, reaction times to determine whether or not word strings constituted acceptable English phrases were measured. Classification times were significantly faster to idiom than to matched control phrases. This effect held under conditions involving different categories of idioms, different transitional probabilities among words in the phrases, and different levels of awareness of the presence of idioms in the materials. The data support a Lexical Representation Hypothesis for the processing of idioms.