Publications

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

This paper investigates the interaction between acoustic scores and symbolic mismatch penalties in multi-pass speech decoding techniques that are based on the creation of a segment graph followed by a lexical search. The interaction between acoustic and symbolic mismatches determines to a large extent the structure of the search space of these multipass approaches. The background of this study is a recently developed computational model of human word recognition, called SpeM. SpeM is able to simulate human word recognition data and is built as a multi-pass speech decoder. Here, we focus on unravelling the structure of the search space that is used in SpeM and similar decoding strategies. Finally, we elaborate on the close relation between distances in this search space, and distance measures in search spaces that are based on a combination of acoustic and phonetic features.

Abstract

This paper reports two experiments with vowels and consonants as phoneme detection targets in real words. In the first experiment, two relatively distinct vowels were compared with two confusible stop consonants. Response times to the vowels were longer than to the consonants. Response times correlated negatively with target phoneme length. In the second, two relatively distinct vowels were compared with their corresponding semivowels. This time, the vowels were detected faster than the semivowels. We conclude that response time differences between vowels and stop consonants in this task may reflect differences between phoneme categories in the variability of tokens, both in the acoustic realisation of targets and in the' representation of targets by subjects.

Abstract

Pitch, intonation, and speech rate were analyzed in a collection of everyday speech heard by one Dutch infant between the ages of six and nine months. Components of each of these variables were measured in the speech of three adult speakers (mother, father, baby-sitter) when they addressed the infant, and when they addressed another adult. The results are in line with previously reported findings which are usually based on laboratory or prearranged settings: infant-directed speech in a natural setting exhibits more pitch variation, a larger number of simple intonation contours, and slower speech rate than does adult-directed speech.

Abstract

Dutch distinguishes at least four sentence types: statements and questions, the latter type being subdivided into wh-questions (beginning with a question word), yes/no-questions (with inversion of subject and finite), and declarative questions (lexico-syntactically identical to statement). Acoustically, each of these (sub)types was found to have clearly distinct global F0-patterns, as well as a characteristic distribution of final rises [1,2]. The present paper explores the separate contribution of parameters of global downtrend and size of accent-lending pitch movements versus aspects of the terminal rise to the human identification of the four sentence (sub)types, at various positions in the time-course of the utterance. The results show that interrogativity in Dutch can be identified at an early point in the utterance. However, wh-questions are not distinct from statements.

Abstract

Articulatory data are used to address the question of whether Dutch schwa insertion is a phonological or a phonetic process. By investigating tongue tip raising and dorsal lowering, we show that /l/ when it appears before inserted schwa is a light /l/, just as /l/ before an underlying schwa is, and unlike the dark /l/ before a consonant in non-insertion productions of the same words. The fact that inserted schwa can condition the light/dark /l/ alternation shows that schwa insertion involves the phonological insertion of a segment rather than phonetic adjustments to articulations.

Abstract

This dissertation focuses on syntactic comprehension problems in patients with Broca's aphasia from an electrophysiological perspective. The central objective of this dissertation was to further explore what syntax-related event-related brain potential (ERP) effects can reveal about the nature of the deficit that underlies syntactic comprehension problems in patients with Broca's aphasia. Chapter two to four describe experiments in which event-related brain potentials were recorded while subjects (Broca patients, non-aphasic patients with a right-hemisphere lesion, and healthy elderly controls) were presented with sentences that contained either violations of syntactic constraints or were syntactically correct. Chapter two investigates ERP effects of subject-verb agreement violations in the different subject groups, and seeks to answer the following questions: Do agrammatic comprehenders show sensitivity to subject-verb agreement violations as indicated by a syntax-related ERP effect? In addition, does the severity of the syntactic comprehension impairment in the Broca patients affect the ERP responses? Chapter three describes an investigation of whether Broca patients show sensitivity to violations of word order as indicated by a syntax-related ERP effect, and whether the ERP responses in the Broca patients are affected by the severity of their syntactic comprehension impairment. Chapter four reports on ERP effects of violations of word-category. In addition, also a semantic violation condition was added to track possible dissociations in the sensitivity to semantic and syntactic information in the Broca patients. Chapter five describes the development of a paradigm in which the electrophysiological approach and the classical sentence-picture matching approach are combined. In this chapter, the ERP method is applied to study on-line thematic role assignment in Broca patients during sentence-picture matching. Also the relation between ERP effects and behavioral responses is pursued. Finally, Chapter 6 provides a summary of the main findings of the experiments and a general discussion.

Abstract

Recent studies using phoneme detection tasks have shown that spoken-language processing is neither facilitated nor interfered with by optional assimilation, but is inhibited by violation of obligatory assimilation. Interpretation of these results depends on an assessment of their generality, specifically, whether they also obtain when listeners are processing nonnative language. Two separate experiments are presented in which native listeners of German and native listeners of Dutch had to detect a target fricative in legal monosyllabic Dutch nonwords. All of the nonwords were correct realisations in standard Dutch. For German listeners, however, half of the nonwords contained phoneme strings which violate the German fricative assimilation rule. Whereas the Dutch listeners showed no significant effects, German listeners detected the target fricative faster when the German fricative assimilation was violated than when no violation occurred. The results might suggest that violation of assimilation rules does not have to make processing more difficult per se.