Publications

Abstract

In deze bijdrage wordt een modulair model van zinsproductie besproken. De planningsprocessen, die aan de productie van een zin voorafgaan, kunnen in twee hoofdcomponenten onderverdeeld worden: deconceptualisering (het bedenken van de inhoud van de uiting) en de formulering (het vastleggen van de linguïstische vorm). Het formuleringsproces bestaat weer uit twee componenten, te weten de grammatische en fonologische codering. Ook deze componenten bestaan elk weer uit een aantal subcomponenten. Dit artikel beschrijft wat de specifieke taak van iedere component is, hoe deze uitgevoerd wordt en hoe de componenten samenwerken. Tevens worden enkele belangrijke methoden van taalproductie-onderzoek besproken.

Abstract

Four experiments investigated the span of advance planning for phrases and short sentences. Dutch subjects were presented with pairs of objects, which they named using noun-phrase conjunctions (e.g., the translation equivalent of ''the arrow and the bag'') or sentences (''the arrow is next to the bag''). Each display was accompanied by an auditory distracter, which was related in form or meaning to the first or second noun of the utterance or unrelated to both. For sentences and phrases, the mean speech onset time was longer when the distracter was semantically related to the first or second noun and shorter when it was phonologically related to the first noun than when it was unrelated. No phonological facilitation was found for the second noun. This suggests that before utterance onset both target lemmas and the first target form were selected.

Abstract

Investigations of the effects of advance information on movement preparation in Parkinson's disease using reaction time (RT) measures have yielded contradictory results. In order to obtain direct information regarding the time course of movement preparation, we combined RT measurements in a movement precueing task with multi-channel recordings of movement-related potentials in the present study. Movements of the index and middle fingers of the left and right hand were either precued or not by advance information regarding the side (left or right hand) of the required response. Reaction times were slower for patients than for control subjects. Both groups benefited equally from informative precues, indicating that patients utilized the advance information as effectively as control subjects. Lateralization of the movement-preceding cerebral activity [i.e. the lateralized readiness potential (LRP)] confirmed that patients used the available partial information to prepare their responses and started this process no later than controls. In conjunction with EMG onset times, the LRP onset measures allowed for a fractionation of the RTs, which provided clues to the stages where the slowness of Parkinson's disease patients might arise. No definite abnormalities of temporal parameters were found, but differences in the distribution of the lateralized movement-preceding activity between patients and controls suggested differences in the cortical organization of movement preparation. Differences in amplitude of the contingent negative variation (CNV) and differences in the way in which the CNV was modulated by the information given by the precue pointed in the same direction. A difference in amplitude of the P300 between patients and controls suggested that preprogramming a response required more effort from. patients than from control subjects.

Abstract

P. A. Starreveld and W. La Heij (1995) tested the seriality view of lexical access in speech production, according to which lexical selection and the encoding of a word's form proceed in serial order without feedback. In 2 experiments, they looked at the combined effect of semantic and orthographic relatedness of written distracter words in tasks that required conceptually driven naming. They found an interaction between semantic relatedness and orthographic relatedness and argued that the observed interaction refutes the seriality view of lexical access. In this comment, the authors argue that Starreveld and La Heij's rejection of serial access was based on an oversimplified conception of the seriality view and that interaction, rather than additivity, is predicted by existing conceptions of serial access.

Abstract

The CELEX lexical database includes a list of Dutch syllables and their frequencies, based on syllabification of isolated word forms. In connected speech, however, sentence-level phonological rules can modify the syllables and their token frequencies. In order to estimate the changes syllables may undergo in connected speech, an empirical investigation was carried out. A large Dutch text corpus (TROUW) was transcribed, processed by word level rules, and syllabified. The resulting lexeme syllables were evaluated by comparing them to the CELEX lexical database for Dutch. Then additional phonological sentence-level rules were applied to the TROUW corpus, and the frequencies of the resulting connected speech syllables were compared with those of the lexeme syllables from TROUW. The overall correlation between lexeme and speech syllables was very high. However, speech syllables generally had more complex CV structures than lexeme syllables. Implications of the results for research involving syllables are discussed. With respect to the notion of a mental syllabary (a store for precompiled articulatory programs for syllables, see Levelt & Wheeldon, 1994) this study revealed an interesting statistical result. The calculation of the cumulative syllable frequencies showed that 85% of the syllable tokens in Dutch can be covered by the 500 most frequent syllable types, which makes the idea of a syllabary very attractive.

Abstract

In their comment, Dell and O'Seaghdha (1991) adduced any effect on phonological probes for semantic alternatives to the activation of these probes in the lexical network. We argue that that interpretation is false and, in addition, that the model still cannot account for our data. Furthermore, and different from Dell and O'seaghda, we adduce semantic rebound to the lemma level, where it is so substantial that it should have shown up in our data. Finally, we question the function of feedback in a lexical network (other than eliciting speech errors) and discuss Dell's (1988) notion of a unified production-comprehension system.

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

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.