Publications

Abstract

This paper addressed the question of how British English, German and Dutch listeners differ in their perception of continuation intonation both at the phonological level (Experiment 1) and at the level of phonetic implementation (Experiment 2). In Experiment 1, preference scores of pitch contours to signal continuation at the clause-boundary were obtained from these listener groups. It was found that among contours with H%, British English listeners had a strong preference for H*L H%, as predicted. Unexpectedly, British English listeners rated H* H% noticeably more favourably than L*H H%; Dutch listeners largely rated H* H% more favourably than H*L H% and L*H H%; German listeners rated these contours similarly and seemed to have a slight preference for H*L H%. In Experiment 2, the degree to which a final rise was perceived to express continuation was established for each listener group in a made-up language. It was found that although all listener groups associated a higher end pitch with a higher degree of continuation likelihood, the perceived meaning difference for a given interval of end pitch heights varied with the contour shape of the utterance final syllable. When it was comparable to H* H%, British English and Dutch listeners perceived a larger meaning difference than German listeners; when it was comparable to H*L H%, British English listeners perceived a larger difference than German and Dutch listeners. This shows that language-specificity in continuation intonation at the phonological level affects the perception of continuation intonation at the phonetic level.

Abstract

Two groups of listeners with Dutch and British English language backgrounds judged Dutch and British English utterances, respectively, which varied in the intonation contour on the scales EMPHATIC vs. NOT EMPHATIC and SURPRISED vs. NOT SURPRISED, two meanings derived from the Effort Code. The stimuli, which differed in sentence mode but were otherwise lexically equivalent, were varied in peak height, peak alignment, end pitch, and overall register. In both languages, there are positive correlations between peak height and degree of emphasis, between peak height and degree of surprise, between peak alignment and degree of surprise, and between pitch register and degree of surprise. However, in all these cases, Dutch stimuli lead to larger perceived meaning differences than the British English stimuli. This difference in the extent to which increased pitch height triggers increases in perceived emphasis and surprise is argued to be due to the difference in the standard pitch ranges between Dutch and British English. In addition, we found a positive correlation between pitch register and the degree of emphasis in Dutch, but a negative correlation in British English. This is an unexpected difference, which illustrates a case of ambiguity in the meaning of pitch.

Abstract

Same-different discrimination judgments for pairs of Korean stop consonants, or of Japanese syllables differing in phonetic segment length, were made by adult Korean adoptees in the Netherlands, by matched Dutch controls, and Korean controls. The adoptees did not outdo either control group on either task, although the same individuals had performed significantly better than matched controls on an identification learning task. This suggests that early exposure to multiple phonetic systems does not specifically improve acoustic-phonetic skills; rather, enhanced performance suggests retained language knowledge.

Abstract

When we speak, we spontaneously produce gestures (co-speech gestures). Co-speech gestures and speech production are closely interlinked. However, the exact nature of the link is still under debate. To addressed the question that whether co-speech gestures originate from the speech production system or from a system independent of the speech production, the present study examined the relationship between co-speech and co-thought gestures. Co-thought gestures, produced during silent thinking without speaking, presumably originate from a system independent of the speech production processes. We found a positive correlation between the production frequency of co-thought and co-speech gestures, regardless the communicative function that co-speech gestures might serve. Therefore, we suggest that co-speech gestures and co-thought gestures originate from a common system that is independent of the speech production processes

Abstract

The present study investigated the effect of orthography on the learning and subsequent processing of pronunciation variants in a second language. Dutch learners of French learned reduced pronunciation variants that result from schwa-zero alternation in French (e.g., reduced /ʃnij/ from chenille 'caterpillar'). Half of the participants additionally learnt the words' spellings, which correspond more closely to the full variants with schwa. On the following day, participants performed an auditory lexical decision task, in which they heard half of the words in their reduced variants, and the other half in their full variants. Participants who had exclusively learnt the auditory forms performed significantly worse on full variants than participants who had also learnt the spellings. This shows that learners integrate phonological and orthographic information to process pronunciation variants. There was no difference between both groups in their performances on reduced variants, suggesting that the exposure to spelling does not impede learners' processing of these variants.

Abstract

Odor naming is difficult for people, but recent cross-cultural research suggests this difficulty is culture-specific. Jahai speakers (hunter-gatherers from the Malay Peninsula) name odors as consistently as colors, and much better than English speakers (Majid & Burenhult, 2014). In Jahai the linguistic advantage for smells correlates with a cultural interest in odors. Here we ask whether sub-cultures in the West with odor expertise also show superior odor naming. We tested wine and coffee experts (who have specialized odor training) in an odor naming task. Both wine and coffee experts were no more accurate or consistent than novices when naming odors. Although there were small differences in naming strategies, experts and non-experts alike relied overwhelmingly on source-based descriptions. So the specific language experts speak continues to constrain their ability to express odors. This suggests expertise alone is not sufficient to overcome the limits of language in the domain of smell.

Abstract

Speech segmentation procedures may differ in speakers of different languages. Earlier work based on French speakers listening to French words suggested that the syllable functions as a segmentation unit in speech processing. However, while French has relatively regular and clearly bounded syllables, other languages, such as English, do not. No trace of syllabifying segmentation was found in English listeners listening to English words, French words, or nonsense words. French listeners, however, showed evidence of syllabification even when they were listening to English words. We conclude that alternative segmentation routines are available to the human language processor. In some cases speech segmentation may involve the operation of more than one procedure.

Abstract

The Possible Word Constraint is a proposed mechanism whereby listeners avoid recognising words spuriously embedded in other words. It applies to words leaving a vowelless residue between their edge and the nearest known word or syllable boundary. The present study tests the usefulness of this constraint via lexical statistics of both English and Dutch. The analyses demonstrate that the constraint removes a clear majority of embedded words in speech, and thus can contribute significantly to the efficiency of human speech recognition

Abstract

Assimilation of place of articulation across a nasal and a following stop consonant is obligatory in Japanese, but not in Dutch. In four experiments the processing of assimilated forms by speakers of Japanese and Dutch was compared, using a task in which listeners blended pseudo-word pairs such as ranga-serupa. An assimilated blend of this pair would be rampa, an unassimilated blend rangpa. Japanese listeners produced significantly more assimilated than unassimilated forms, both with pseudo-Japanese and pseudo-Dutch materials, while Dutch listeners produced significantly more unassimilated than assimilated forms in each materials set. This suggests that Japanese listeners, whose native-language phonology involves obligatory assimilation constraints, represent the assimilated nasals in nasal-stop sequences as unmarked for place of articulation, while Dutch listeners, who are accustomed to hearing unassimilated forms, represent the same nasal segments as marked for place of articulation.

Abstract

Dutch listeners outperform native listeners in identifying syllable stress in English. This is because lexical stress is more useful in recognition of spoken words of Dutch than of English, so that Dutch listeners pay greater attention to stress in general. We examined Dutch listeners’ use of the acoustic correlates of English stress. Primary- and secondary-stressed syllables differ significantly on acoustic measures, and some differences, in F0 especially, correlate with data of earlier listening experiments. The correlations found in the Dutch responses were not paralleled in data from native listeners. Thus the acoustic cues which distinguish English primary versus secondary stress are better exploited by Dutch than by native listeners.

Abstract

In contrast to initial L1 vocabularies, which of necessity depend largely on heard exemplars, L2 vocabulary construction can draw on a variety of knowledge sources. This can lead to richer stored knowledge about the phonology of the L2 than the listener's prelexical phonetic processing capacity can support, and thus to mismatch between the level of detail required for accurate lexical mapping and the level of detail delivered by the prelexical processor. Experiments on spoken word recognition in L2 have shown that phonetic contrasts which are not reliably perceived are represented in the lexicon nonetheless. This lexical representation of contrast must be based on abstract knowledge, not on veridical representation of heard exemplars. New experiments confirm that provision of abstract knowledge (in the form of spelling) can induce lexical representation of a contrast which is not reliably perceived; but also that experience (in the form of frequency of occurrence) modulates the mismatch of phonetic and lexical processing. We conclude that a correct account of word recognition in L2 (as indeed in L1) requires consideration of both abstract and episodic information.

Abstract

The difficulty of listening to speech in noise is exacerbated when the speech is in the listener’s L2 rather than L1. In this study, Spanish and Dutch users of English as an L2 identified American English consonants in a constant intervocalic context. Their performance was compared with that of L1 (British English) listeners, under quiet conditions and when the speech was masked by speech from another talker or by noise. Masking affected performance more for the Spanish listeners than for the L1 listeners, but not for the Dutch listeners, whose performance was worse than the L1 case to about the same degree in all conditions. There were, however,large differences in the pattern of results across individual consonants, which were consistent with differences in how consonants are identified in the respective L1s.

Abstract

Languages contain tens of thousands of words, but these are constructed from a tiny handful of phonetic elements. Consequently, words resemble one another, or can be embedded within one another, a coup stick snot with standing. me process of spoken-word recognition by human listeners involves activation of multiple word candidates consistent with the input, and direct competition between activated candidate words. Further, human listeners are sensitive, at an early, prelexical, stage of speeeh processing, to constraints on what could potentially be a word of the language.

Abstract

English and French listeners performed two tasks - click location and speeded click detection - with both English and French sentences, closely matched for syntactic and phonological structure. Clicks were located more accurately in open- than in closed-class words in both English and French; they were detected more rapidly in open- than in closed-class words in English, but not in French. The two listener groups produced the same pattern of responses, suggesting that higher-level linguistic processing was not involved in these tasks.

Abstract

Two phoneme goodness rating experiments addressed the role of orthographic knowledge in the evaluation of speech sounds. Ratings for the best tokens of /s/ were higher in words spelled with S (e.g., bless) than in words where /s/ was spelled with C (e.g., voice). This difference did not appear for analogous nonwords for which every lexical neighbour had either S or C spelling (pless, floice). Models of phonemic processing incorporating obligatory influence of lexical information in phonemic processing cannot explain this dissociation; the data are consistent with models in which phonemic decisions are not subject to necessary top-down lexical influence.

Abstract

The phoneme detection task is widely used in spoken word recognition research. Alphabetically literate participants, however, are more used to explicit representations of letters than of phonemes. The present study explored whether phoneme detection is sensitive to how target phonemes are, or may be, orthographically realised. Listeners detected the target sounds [b,m,t,f,s,k] in word-initial position in sequences of isolated English words. Response times were faster to the targets [b,m,t], which have consistent word-initial spelling, than to the targets [f,s,k], which are inconsistently spelled, but only when listeners’ attention was drawn to spelling by the presence in the experiment of many irregularly spelled fillers. Within the inconsistent targets [f,s,k], there was no significant difference between responses to targets in words with majority and minority spellings. We conclude that performance in the phoneme detection task is not necessarily sensitive to orthographic effects, but that salient orthographic manipulation can induce such sensitivity.

Abstract

The performance of automatic speech recognition systems is usually assessed in terms of error rate. Human speech recognition produces few errors, but relative difficulty of processing can be assessed via response time techniques. We report the construction of a measure analogous to response time in a machine recognition system. This measure may be compared directly with human response times. We conducted a trial comparison of this type at the phoneme level, including both tense and lax vowels and a variety of consonant classes. The results suggested similarities between human and machine processing in the case of consonants, but differences in the case of vowels.

Abstract

In a production experiment on Bulgarian that was based on a previous study on Dutch [1], we investigated the role of prosody when linguistic and extra-linguistic information coincide or contradict. Speakers described abnormally colored fruits in conditions where contrastive focus and discourse relations were varied. We found that the coincidence of contrast and abnormality enhances accentuation in Bulgarian as it did in Dutch. Surprisingly, when both factors are in conflict, the prosodic prominence of abnormality often overruled focus accentuation in both Bulgarian and Dutch, though the languages also show marked differences.

Abstract

This paper discusses the influence of age-related factors like stage of cognitive development, prior linguistic knowledge, and motivation and addresses the specific effects of these ‘age factors’ on second language acquisition as opposed to other learning tasks. Based on longitudinal corpus data from child and adolescent learners of L2 German (L1 = Russian), the paper studies the acquisition of word order (verb raising over negation, verb second) and inflectional morphology (subject-verb-agreement, tense, noun plural, and adjective-noun agreement). Whereas the child learner shows target-like production in all of these areas within the observation period (1½ years), the adolescent learner masters only some of them. The discussion addresses the question of what it is about clusters of grammatical features that make them particularly affected by age.

Abstract

Informal paraphrases by native speaker consultants are crucial tools in linguistic fieldwork. When recorded, archived, and analysed, they offer rich data that can be mined for many purposes, from lexicography to semantic typology and from ethnography to the investigation of gesture and speech. This paper describes a procedure for the collection and analysis of folk definitions that are native (in the language under study rather than the language of analysis), informal (spoken rather than written), and multi-modal (preserving the integrity of gesture-speech composite utterances). The value of folk definitions is demonstrated using the case of ideophones, words that are notoriously hard to study using traditional elicitation methods. Three explanatory strategies used in a set of folk definitions of ideophones are examined: the offering of everyday contexts of use, the use of depictive gestures, and the use of sense relations as semantic anchoring points. Folk definitions help elucidate word meanings that are hard to capture, bring to light cultural background knowledge that often remains implicit, and take seriously the crucial involvement of native speaker consultants in linguistic fieldwork. They provide useful data for language documentation and are an essential element of any toolkit for linguistic and ethnographic field research.

Abstract

Some languages describe musical pitch in terms of spatial height; others in terms of thickness. Differences in pitch metaphors also shape adults’ nonlinguistic space-pitch representations. At the same time, 4-month-old infants have both types of space-pitch mappings available. This tension between prelinguistic space-pitch associations and their subsequent linguistic mediation raises questions about the acquisition of space-pitch metaphors. To address this issue, 5-year-old Dutch children were tested on their linguistic knowledge of pitch metaphors, and nonlinguistic space-pitch associations. Our results suggest 5-year-olds understand height-pitch metaphors in a reversed fashion (high pitch = low). Children displayed good comprehension of a thickness-pitch metaphor, despite its absence in Dutch. In nonlinguistic tasks, however, children did not show consistent space-pitch associations. Overall, pitch representations do not seem to be influenced by linguistic metaphors in 5-year-olds, suggesting that effects of language on musical pitch arise rather late during development.

Abstract

Research into sound-symbolism has shown that people can
consistently associate certain pseudo-words with certain referents;
for instance, pseudo-words with rounded vowels and
sonorant consonants are linked to round shapes, while pseudowords
with unrounded vowels and obstruents (with a noncontinuous
airflow), are associated with sharp shapes. Such
sound-symbolic associations have been proposed to arise from
cross-modal abstraction processes. Here we assess the link between
sound-symbolism and cross-modal abstraction by testing
dyslexic individuals’ ability to make sound-symbolic associations.
Dyslexic individuals are known to have deficiencies
in cross-modal processing. We find that dyslexic individuals
are impaired in their ability to make sound-symbolic associations
relative to the controls. Our results shed light on the cognitive
underpinnings of sound-symbolism by providing novel
evidence for the role —and disruptability— of cross-modal abstraction
processes in sound-symbolic eects.

Abstract

This paper summarizes the results of a descriptive syntactic category analysis of child English no which reveals that young children use and represent no as a determiner and negatives like no pen as NPs, contra standard analyses.

Abstract

Previous research revealed remarkable flexibility of native and non-native listeners’ perceptual system, i.e., native and non-native phonetic category boundaries can be quickly recalibrated in the face of ambiguous input.
The present study investigates the limitations of the flexibility of the non-native perceptual system. In two lexically-guided perceptual learning experiments, Dutch listeners were exposed to a short story in English, where either all /l/ or all /ɹ/ sounds were replaced by an ambiguous [l/ɹ] sound. In the first experiment, the story was presented in clean, while in the second experiment, intermittent noise was added to the story, although never on the critical words. Lexically-guided perceptual learning was only observed in the clean condition. It is argued that the introduction of intermittent noise reduced the reliability of the evidence of hearing a particular word, which in turn blocked retuning of the phonetic categories.

Abstract

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

Abstract

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

Abstract

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

Abstract

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

Abstract

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

Abstract

This study addresses the roles of segment deletion, durational reduction, and frequency of use in the comprehension of morphologically complex words. We report two auditory lexical decision experiments with reduced and unreduced prefixed Dutch words. We found that segment deletions as such delayed comprehension. Simultaneously, however, longer durations of the different parts of the words appeared to increase lexical competition, either from the word’s stem (Experiment 1) or from the word’s morphological continuation forms (Experiment 2). Increased lexical competition slowed down especially the comprehension of low frequency words, which shows that speakers do not try to meet listeners’ needs when they reduce especially high frequency words.

Abstract

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

Abstract

This paper investigates how listeners process regular pronunciation variants, resulting from simple general reduction processes. Study 1 shows that when listeners are presented with new words, they store the pronunciation variants presented to them, whether these are unreduced or reduced. Listeners thus store information on word-specific pronunciation variation. Study 2 suggests that if participants are presented with regularly reduced pronunciations, they also reconstruct and store the corresponding unreduced pronunciations. These unreduced pronunciations apparently have special status. Together the results support hybrid models of speech processing, assuming roles for both exemplars and abstract representations.

Abstract

The larynx is the essential articulatory mechanism that primes the vocal tract. Far from being only a glottal source of voicing, the complex laryngeal mechanism entrains the ontogenetic acquisition of speech and, through coarticulatory coupling, guides the production of oral sounds in the infant vocal tract. As such, it is not possible to speculate as to the origins of the speaking modality in humans without considering the fundamental role played by the laryngeal articulatory mechanism. The Laryngeal Articulator Model, which divides the vocal tract into a laryngeal component and an oral component, serves as a basis for describing early infant speech and for positing how speech sounds evolving in various hominids may be related phonetically. To this end, we offer some suggestions for how the evolution and development of vocal tract anatomy fit with our infant speech acquisition data and discuss the implications this has for explaining phonetic learning and for interpreting the biological evolution of the human vocal tract in relation to speech and speech acquisition.

Abstract

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

Abstract

The aim of the present work is to identify the evolutionary origins of the ability to speak and understand a natural language. I will adopt Botha’s “Windows Approach” (Language and Communication, 2006, 26, pp. 129–143) in order to justify the following two assumptions, which concern the evolutionary continuity between human language and animals’ communication systems: (a) despite the uniqueness of human language in sharing and conveying utterances with an open-ended structure, some isolated components of our linguistic competence are shared with non- human primates, grounding a line of evolutionary continuity; (b) the very first “linguistic” utterances were holistic, that is, whole bunches of sounds able to convey information despite their lack of modern syntax. I will address such suppositions through the comparative analysis of three constitutive features of human language: syntax, the semantic value of utterances, and the ability to attribute mental states to conspecifics, i.e. the theory of mind.

Abstract

This chapter highlights the research in isolating genetic factors underlying specific language impairment (SLI), or developmental dysphasia, which exploits newly developed genotyping technology, novel statistical methodology, and DNA sequence data generated by the Human Genome Project. The author begins with an overview of results from family, twin, and adoption studies supporting genetic involvement and then goes on to outline progress in a number of genetic mapping efforts that have been recently completed or are currently under way. It has been possible for genetic researchers to pinpoint the specific mutation responsible for some speech and language disorders, providing an example of how the availability of human genomic sequence data can greatly accelerate the pace of disease gene discovery. Finally, the author discusses future prospects on how molecular genetics may offer new insight into the etiology underlying speech and language disorders, leading to improvements in diagnosis and treatment.

Abstract

Children learn their mother tongue spontaneously and effortlessly through communicative interaction with their environment; they do not have to be taught explicitly or learn how to learn first. The ambient language to which children are exposed, however, is highly variable and arguably deficient with regard to the learning target. Nonetheless, most normally developing children learn their native language rapidly and with ease. To explain this accomplishment, many theories of acquisition posit innate constraints on learning, or even a biological endowment for language which is specific to language. Usage-based theories, on the other hand, place more emphasis on the role of experience and domain-general learning mechanisms than on innate language-specific knowledge. But languages are lexically open and combinatorial in structure, so no amount of experience covers their expressivity. Usage-based theories therefore have to explain how children can generalize the properties of their linguistic input to an adult-like grammar. In this thesis I provide an explicit computational mechanism with which usage-based theories of language can be tested and evaluated. The focus of my work lies on complex syntax and the human ability to form sentences which express more than one proposition by means of relativization. This `capacity for recursion' is a hallmark of an adult grammar and, as some have argued, the human language faculty itself. The manuscript is organized as follows. In the second chapter, I give an overview of results that characterize the properties of neural networks as mathematical objects and review previous attempts at modelling the acquisition of complex syntax with such networks. The chapter introduces the conceptual landscape in which the current work is located. In the third chapter, I argue that the construction and use of meaning is essential in child language acquisition and adult processing. Neural network models need to incorporate this dimension of human linguistic behavior. I introduce the Dual-path model of sentence production and syntactic development which is able to represent semantics and learns from exposure to sentences paired with their meaning (cf. Chang et al. 2006). I explain the architecture of this model, motivate critical assumptions behind its design, and discuss existing research using this model. The fourth chapter describes and compares several extensions of the basic architecture to accommodate the processing of multi-clause utterances. These extensions are evaluated against computational desiderata, such as good learning and generalization performance and the parsimony of input representations. A single-best solution for encoding the meaning of complex sentences with restrictive relative clauses is identified, which forms the basis for all subsequent simulations. Chapter five analyzes the learning dynamics in more detail. I first examine the model's behavior for different relative clause types. Syntactic alternations prove to be particularly difficult to learn because they complicate the meaning-to-form mapping the model has to acquire. In the second part, I probe the internal representations the model has developed during learning. It is argued that the model acquires the argument structure of the construction types in its input language and represents the hierarchical organization of distinct multi-clause utterances. The juice of this thesis is contained in chapters six to eight. In chapter six, I test the Dual-path model's generalization capacities in a variety of tasks. I show that its syntactic representations are sufficiently transparent to allow structural generalization to novel complex utterances. Semantic similarities between novel and familiar sentence types play a critical role in this task. The Dual-path model also has a capacity for generalizing familiar words to novel slots in novel constructions (strong semantic systematicity). Moreover, I identify learning conditions under which the model displays recursive productivity. It is argued that the model's behavior is consistent with human behavior in that production accuracy degrades with depth of embedding, and right-branching is learned faster than center-embedding recursion. In chapter seven, I address the issue of learning complex polar interrogatives in the absence of positive exemplars in the input. I show that the Dual-path model can acquire the syntax of these questions from simpler and similar structures which are warranted in a child's linguistic environment. The model's errors closely match children's errors, and it is suggested that children might not require an innate learning bias to acquire auxiliary fronting. Since the model does not implement a traditional kind of language-specific universal grammar, these results are relevant to the poverty of the stimulus debate. English relative clause constructions give rise to similar performance orderings in adult processing and child language acquisition. This pattern matches the typological universal called the noun phrase accessibility hierarchy. I propose an input-based explanation of this data in chapter eight. The Dual-path model displays this ordering in syntactic development when exposed to plausible input distributions. But it is possible to manipulate and completely remove the ordering by varying properties of the input from which the model learns. This indicates, I argue, that patterns of interference and facilitation among input structures can explain the hierarchy when all structures are simultaneously learned and represented over a single set of connection weights. Finally, I draw conclusions from this work, address some unanswered questions, and give a brief outlook on how this research might be continued.

Abstract

We present a neural-symbolic learning model of sentence production which displays strong semantic systematicity and recursive productivity. Using this model, we provide evidence for the data-driven learnability of complex yes/no- questions.

Abstract

Los idiomas sudamericanas tienen una diversidad de sistemas numéricos, desde sistemas con solamente dos o tres términos en algunos idiomas amazónicos hasta sistemas con numerales extendiendo a miles. Una mirada al sistema del idioma cha’palaa de Ecuador demuestra rasgos de base-2, base-5, base-10 y base-20, ligados a diferentes etapas de cambio, desarrollo y contacto lingüístico. Conocer estas etapas nos permite proponer algunas correlaciones con lo que conocemos de la historia de contactos culturales en la región. The South American languages have diverse types of numeral systems, from systems of just two or three terms in some Amazonian languages to systems extending into the thousands. A look a the system of the Cha'palaa language of Ecuador demonstrates base-2, base-5, base-10 and base-20 features, linked to different stages of change, development and language contact. Learning about these stages permits up to propose some correlations between them and what we know about the history of cultural contact in the region.

Abstract

In a 2x2 event-related FMRI study we find support for the idea that the inferior frontal cortex, centered on Broca’s region and its homologue, is involved in constructive unification operations during the structure-building process in parsing for comprehension. Tentatively, we provide evidence for a role of the dorsolateral prefrontal cortex centered on BA 9/46 in the control component of the language system. Finally, the left temporo-parietal cortex, in the vicinity of Wernicke’s region, supports the interaction between the syntax of gender agreement and sentence-level semantics.

Abstract

Human implicit learning can be investigated with implicit artificial grammar learning, a simple model for aspects of natural language acquisition. In this paper we investigate the remaining effect of modality transfer in syntactic classification of an acquired grammatical sequence structure after implicit grammar acquisition. Participants practiced either on acoustically presented syllable sequences or visually presented consonant letter sequences. During classification we independently manipulated the statistical frequency-based and rule-based characteristics of the classification stimuli. Participants performed reliably above chance on the within modality classification task although more so for those working on syllable sequence acquisition. These subjects were also the only group that kept a significant performance level in transfer classification. We speculate that this finding is of particular relevance in consideration of an ecological validity in the input signal in the use of artificial grammar learning and in language learning paradigms at large.

Abstract

The molecular, developmental, and evolutionary bases of human brain asymmetry are almost completely unknown. Genetic linkage and association mapping have pin-pointed a gene called LRRTM1 (leucine-rich repeat transmembrane neuronal 1) that may contribute to variability in human handedness. Here I describe how LRRTM1's involvement in handedness was discovered, and also the latest knowledge of its functions in brain development and disease. The association of LRRTM1 with handedness was derived entirely from the paternally inherited gene, and follow-up analysis of gene expression confirmed that LRRTM1 is one of a small number of genes that are imprinted in the human genome, for which the maternally inherited copy is suppressed. The same variation at LRRTM1 that was associated paternally with mixed-/left-handedness was also over-transmitted paternally to schizophrenic patients in a large family study.
LRRTM1 is expressed in specific regions of the developing and adult forebrain by post-mitotic neurons, and the protein may be involved in axonal trafficking. Thus LRRTM1 has a probable role in neurodevelopment, and its association with handedness suggests that one of its functions may be in establishing or consolidating human brain asymmetry.
LRRTM1 is the first gene for which allelic variation has been associated with human handedness. The genetic data also suggest indirectly that the epigenetic regulation of this gene may yet prove more important than DNA sequence variation for influencing brain development and disease.
Intriguingly, the parent-of-origin activity of LRRTM1 suggests that men and women have had conflicting interests in relation to the outcome of lateralized brain development in their offspring.

Abstract

This study aims to test a prediction of recent
theoretical frameworks in speech motor control: if speech production targets are specified in auditory
terms, people with better auditory acuity should have more precise speech targets.
To investigate this, we had participants perform speech perception and production tasks in a counterbalanced order. To assess speech perception acuity, we used an adaptive speech discrimination
task. To assess variability in speech production, participants performed a pseudo-word reading task; formant values were measured for each recording.
We predicted that speech production variability to correlate inversely with discrimination performance.
The results suggest that people do vary in their production and perceptual abilities, and that better discriminators have more distinctive vowel production targets, confirming our prediction. This
study highlights the importance of individual
differences in the study of speech motor control, and sheds light on speech production-perception interaction.

Abstract

This paper presents a new architecture for optical burst switched networks where the control plane of the network functions in a cooperative manner. Each node interprets the data conveyed by the control packet and forwards it to the next nodes, making the control plane of the network distribute the relevant information to all the nodes in the network. A cooperation transmission tree is used, thus allowing all the nodes to store the information related to the traffic management in the network, and enabling better network resource planning at each node. A model of this network architecture is proposed, and its performance is evaluated.

Abstract

This doctoral dissertation investigated the learning of auditory categories by applying insights from child language learning, visual category learning and phonetic categorization by adults. The experiments in chapter 2 concern supervised learning of multidimensional non-speech categories varying in two dimensions: duration and a non speech analogue of formant frequency. In experiment 1, one dimension of variation determined category membership, variation in the other dimension was irrelevant. Listeners quickly learned to categorize according to this distinction. In experiment 2, both dimensions needed to be combined to categorize correctly. Performance was much lower, but most listeners succeeded in this task. However, in a maintenance phase without feedback or distributional information, listeners reverted to a unidimensional solution. In a maintenance phase with distributional information, listeners did use both dimensions correctly, arguing for the importance of distributional information in (auditory) category acquisition. In chapter 3, the listeners had to classify the same categories, but without feedback. In experiment 1, listeners succeeded to discover the relevant dimension of variation (and ignore the irrelevant one) without feedback. Much of this learning was lost in the maintenance phase, especially for the dimension formant frequency. With two relevant dimensions (Experiment 2), listeners were not able to learn to use both dimensions and reverted to a unidimensional solution. Chapter 4 applied the paradigms of chapter 2 and 3 to the learning of speech categories. Spanish native listeners learned Dutch vowel contrast with one relevant dimension of variation. With feedback, learning was swift, although was not well maintained without feedback or distributional information. Without feedback, Spanish listeners reverted to the dimensions best known in their native phonology, formant frequency, even when distributional information pointed to duration. The results are discussed in chapter 5. The implications for models of speech acquisition are discussed.

Abstract

Distributional learning is almost certainly involved in the human acquisition of phonetic categories. Because speech is inherently a multidimensional signal, learning phonetic categories entails multidimensional learning. Yet previous studies of auditory category learning have shown poor maintenance of learned multidimensional categories. Two experiments explored ways to improve maintenance: by increasing the costs associated with applying a unidimensional strategy; by providing additional information about the category structures; and by giving explicit instructions on how to categorize. Only with explicit instructions were categorization strategies maintained in a maintenance phase without supervision or distributional information.

Abstract

In this paper we introduce Functional Data Analysis (FDA) as a tool for analyzing dynamic transitions in speech signals. FDA makes it possible to perform statistical analyses of sets of mathematical functions in the same way as classical multivariate analysis treats scalar measurement data. We illustrate the use of FDA with a reduction phenomenon affecting the French word c'était /setε/ 'it was', which can be reduced to [stε] in conversational speech. FDA reveals that the dynamics of the transition from [s] to [t] in fully reduced cases may still be different from the dynamics of [s] - [t] transitions in underlying /st/ clusters such as in the word stage.