Biomedical subjects
Publications and source records attributed to W A van Dommelen.
It is shown that the results of an experiment on speaker identification described by Whiteside and Rixon in 2000 seem to be contradictory and inconclusive. To investigate whether the experiment allows reliable conclusions, re-evaluation of their data using multiple regression techniques is proposed.
This study investigates the influence of fundamental frequency (F0) contour on perceived vowel duration in Norwegian. In the first of four experiments, a falling vs. flat contour in short vs. long vowels in isolated monosyllables was shown to cause a perceptual lengthening of the vowel. Contrary to the expectations, embedding the monosyllables sentence-medially in experiment 2 did not turn the lengthening into a shortening effect. Also unexpectedly, a rising vs. flat contour did not influence perceived duration in monosyllables (experiment 3). Experiment 4 focused on falling as well as rising contours in disyllabic test words. Here, too, a lengthening effect was found only for a falling pattern. In parallel with experiment 2, the presence of the test word's second syllable did not turn perceptual lengthening into perceptual shortening. Comparison of the present results with data previously reported for German leads to the conclusion that the interaction of F0 contour and perceived vowel duration is language-specific and cannot be explained by assuming a universal psychophysical mechanism.
The present paper is a continuation of a previous study, in which several cues in French stop consonant perception were investigated. In a first series of experiments, identification of a stop as fortis versus lenis turned out to be influenced by whether the following consonant was a fricative or a plosive. Taking the results of this first series as a point of departure, the next experiment focussed on the possible masking influence of friction noise on the perception of a preceding stop. This hypothesis, however, was not confirmed by the outcome of the experiment. Two further experiments showed that periodicity in a stop plus stop cluster is assigned to the first or the second stop, depending on its position in the cluster, even when the first stop is not released. The general discussion places the results within a general frame of consonant perception in French.
This investigation takes as its point of departure observations on the production of French fortis versus lenis plosive consonants. In a series of perception tests the role of different parameters in the fortis versus lenis distinction found in production (e.g. duration of the pre-consonantal vowel, the consonantal closure, voicing during the closure and intensity of the consonantal release noise) was investigated. Apart from durational and intensity parameters, vowel quality differences (depending on the fortis versus lenis character of the following consonant) are also shown to play a part in phoneme identification. Furthermore it is shown that in obstruent clusters like /tp, dp/ versus /tg, dg/ not only do phonetic parameters like those mentioned above influence perception, but that also the phonemic identity of /p/ versus /g/ as fortis versus lenis contributes to the hearers' decision about the identity of the first consonant in the cluster. Phonetic as well as contextual factors are shown to interact in a complex manner. Implications of the results for speech perception theory are discussed.
Four speaker identification tests were conducted using five female speakers known to the listeners. Starting from acoustic recordings of reiterant "ma" syllables, the perceptual importance of the following three factors was investigated: F0 height, F0 contour, and speech rhythm. For speakers with typically low or high voices F0 height turned out to be a highly relevant cue in speaker identification. For all speakers F0 contour was of secondary importance, whereas speech rhythm had a small but consistent influence on recognition rates. It could be inferred that remaining factors alone (mainly global spectral information) would yield recognition scores of approximately 50%. Consistent with previous investigations, the relevance of perceptual cues in the recognition of familiar voices was shown to be not hierarchically fixed, but to depend on speaker-specific voice characteristics.
This study examines the ability of listeners to judge speaker height and weight from speech samples. Although previous investigations indicate that listeners are consistent in estimating body characteristics, it is not known which speech signal parameters are being used by the listeners for such estimates. Therefore, a series of listening tests was carried out in which male and female listeners judged the height and weight from male and female speakers reading isolated words and two text paragraphs. Both speaker sex and listener sex turned out to be important factors: Significant correlations between estimated height/weight and actual height/weight were found only for male speakers. The majority of these estimates came from the male listeners. Neither male nor female listeners, however, were able to estimate female speaker height or weight. Regression analysis involving F0, formant frequencies, energy below 1 kHz, and speech rate showed no significant correlations between these parameters and actually measured speaker height and weight, the only exception being a significant correlation between male speaker weight and speech rate. Furthermore, regression data suggested that the listeners (correctly) used speech rate information in judging male speaker weight, whereas low F0 and formant frequency values (wrongly) were taken to indicate large speaker body dimensions.