Publications

Abstract

In the speech production model proposed by [Levelt, W. J. M., Roelofs, A., Meyer, A. S. (1999). A theory of lexical access in speech production. Behavioral and Brain Sciences, 22, pp. 1-75.], syllables play a crucial role at the interface of phonological and phonetic encoding. At this interface, abstract phonological syllables are translated into phonetic syllables. It is assumed that this translation process is mediated by a so-called Mental Syllabary. Rather than constructing the motor programs for each syllable on-line, the mental syllabary is hypothesized to provide pre-compiled gestural scores for the articulators. In order to find evidence for such a repository, we investigated syllable-frequency effects: If the mental syllabary consists of retrievable representations corresponding to syllables, then the retrieval process should be sensitive to frequency differences. In a series of experiments using a symbol-position association learning task, we tested whether highfrequency syllables are retrieved and produced faster compared to low-frequency syllables. We found significant syllable frequency effects with monosyllabic pseudo-words and disyllabic pseudo-words in which the first syllable bore the frequency manipulation; no effect was found when the frequency manipulation was on the second syllable. The implications of these results for the theory of word form encoding at the interface of phonological and phonetic encoding; especially with respect to the access mechanisms to the mental syllabary in the speech production model by (Levelt et al.) are discussed.

Abstract

Individuals speak incrementally when they interleave planning and articulation. Eyetracking, along with the measurement of speech onset latencies, can be used to gain more insight into the degree of incrementality adopted by speakers. In the current article, two eyetracking experiments are reported in which pairs of complex numerals were named (arabic format, Experiment 1) or read aloud (alphabetic format, Experiment 2) as house numbers and as clock times. We examined whether the degree of incrementality is differentially influenced by the production task (naming vs. reading) and mode (house numbers vs. clock time expressions), by comparing gaze durations and speech onset latencies. In both tasks and modes, dissociations were obtained between speech onset latencies (reflecting articulation) and gaze durations (reflecting planning), indicating incrementality. Furthermore, whereas none of the factors that determined gaze durations were reflected in the reading and naming latencies for the house numbers, the dissociation between gaze durations and response latencies for the clock times concerned mainly numeral length in both tasks. These results suggest that the degree of incrementality is influenced by the type of utterance (house number vs. clock time) rather than by task (reading vs. naming). The results highlight the importance of the utterance structure in determining the degree of incrementality.

Abstract

This study investigated the monitoring of metrical stress information in internally generated speech. In Experiment 1, Dutch participants were asked to judge whether bisyllabic picture names had initial or final stress. Results showed significantly faster decision times for initially stressed targets (e.g., KAno ‘‘canoe’’) than for targets with final stress (e.g., kaNON ‘‘cannon’’; capital letters indicate stressed syllables). It was demonstrated that monitoring latencies are not a function of the picture naming or object recognition latencies to the same pictures. Experiments 2 and 3 replicated the outcome of the first experiment with trisyllabic picture names. These results are similar to the findings of Wheeldon and Levelt (1995) in a segment monitoring task. The outcome might be interpreted to demonstrate that phonological encoding in speech production is a rightward incremental process. Alternatively, the data might reflect the sequential nature of a perceptual mechanism used to monitor lexical stress.

Abstract

In three experiments we test the assumption that idioms have their own lexical entry, which is linked to its constituent lemmas (Cutting & Bock, 1997). Speakers produced idioms or literal phrases (Experiment 1), completed idioms (Experiment 2), or switched between idiom completion and naming (Experiment 3). The results of Experiment 1 show that identity priming speeds up idiom production more effectively than literal phrase production, indicating a hybrid representation of idioms. In Experiment 2, we find effects of both phonological and semantic priming. Thus, elements of an idiom can not only be primed via their wordform, but also via the conceptual level. The results of Experiment 3 show that preparing the last word of an idiom primes naming of both phonologically and semantically related targets, indicating that literal word meanings become active during idiom production. The results are discussed within the framework of the hybrid model of idiom representation.

Abstract

In the present study, the authors examined with event-related brain potentials whether phonological encoding in picture naming is mediated by basic semantic feature retrieval or proceeds independently. In a manual 2-choice go/no-go task the choice response depended on a semantic classification (animal vs. object) and the execution decision was contingent on a classification of name phonology (vowel vs. consonant). The introduction of a semantic task mixing procedure allowed for selectively manipulating the speed of semantic feature retrieval. Serial and parallel models were tested on the basis of their differential predictions for the effect of this manipulation on the lateralized readiness potential and N200 component. The findings indicate that phonological code retrieval is not strictly contingent on prior basic semantic feature processing.

Abstract

Telling time is an exercise in coordinating language production with visual perception. By coupling different ways of saying times with different ways of seeing them, the performance of time-telling can be used to track cognitive transformations from visual to verbal information in connected speech. To accomplish this, we used eyetracking measures along with measures of speech timing during the production of time expressions. Our findings suggest that an effective interface between what has been seen and what is to be said can be constructed within 300 ms. This interface underpins a preverbal plan or message that appears to guide a comparatively slow, strongly incremental formulation of phrases. The results begin to trace the divide between seeing and saying -or thinking and speaking- that must be bridged during the creation of even the most prosaic utterances of a language.

Abstract

A. Caramazza, A. Costa, M. Miozzo, and Y. Bi(2001) reported a series of experiments demonstrating that the ease of producing a word depends only on the frequency of that specific word but not on the frequency of a homophone twin. A. Caramazza, A. Costa, et al. concluded that homophones have separate word form representations and that the absence of frequency-inheritance effects for homophones undermines an important argument in support of 2-stage models of lexical access, which assume that syntactic (lemma) representations mediate between conceptual and phonological representations. The authors of this article evaluate the empirical basis of this conclusion, report 2 experiments demonstrating a frequency-inheritance effect, and discuss other recent evidence. It is concluded that homophones share a common word form and that the distinction between lemmas and word forms should be upheld.

Abstract

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

Abstract

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

Abstract

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