Within-category discrimination of musical chords: Perceptual magnet or anchor?

Abstract

Recent speech research has demonstrated that the presence of prototypes may be reflected in the internal structure of speech categories. Some speech results have found lower discrimination in a vowel P context compared to a NP context, suggesting that a prototype may function as a perceptual magnet, effectively decreasing perceptual distance, and thus, discriminability, between stimuli. The current study examines the function of prototypes in a musical category; another natural, but nonspeech, category. Prototype (P) and nonprototype (NP) sets of major triad stimuli were constructed, with stimuli in the P set being more representative of the category than the NP stimuli. Musically experienced subjects rated the stimuli in each set for goodness as a major triad, with the highest rated stimulus serving as a prototype standard for a subsequent discrimination task. Results from the discrimination task demonstrated better performance in the prototype context. The current nonspeech results appear to follow predictions based on classification and perceptual models (to be discussed), and provide a natural, nonspeech contrast to speech findings. The results will also be addressed in terms of music perception, including aspects such as different temperment systems and the differential importance of chord components.

Internal structure of voicing categories in early infancy

“…However, recent evidence indicates that the perceptual magnet effect found for speech might not always be found for other categories. In particular, Acker, Pastore, and Hall (1995) have reported that for musical chords, discrimination is actually better, rather than worse, in the region of the category prototype. This suggests that category prototypes might function somewhat differently across domains, and that this difference might interact with the type of task used to assess the underlying structure (see also Krumhansl, 1978Krumhansl, , 1979Tversky, 1977).…”

Untutored discrimination training on paired cell images influences visual learning in cytopathology

“…Of course, it is possible to experiment with any of the possible image pair combinations described above, including paired easy/difficult images (ie, eN/dA and dN/eA); there is evidence that both difficult and easy training can be effective. [24][25][26] However, categorical perception theory intuitively suggests that training on paired images drawn from the same diagnostic category (ie, eN/dN or eA/dA) would not be very effective, simply because observers might require exposure to objects from different diagnostic categories if they are to learn to distinguish them. In purely practical terms, we would like to know which of the paired image combinations enhances diagnostic performance most effectively.…”

Better discrimination of small changes in commonly encountered than in less commonly encountered auditory stimuli.

“…The experiment by Acker et al (1995) that was described in the introduction is clearly relevant to the present outcomes. (Their work was unknown to us at the time we conducted the present experiments, but their results suggest that the stimuli do not have to be as complex as were ours for a discrimination advantage to be observed for CE stimuli in this context.)…”

“…One set of relevant demonstrations comes from research on the perception of musical intervals. Acker, Pastore, and Hall (1995) measured auditory frequency discrimination using stimuli consisting of three tones presented simultaneously. One or two of those tones were changed slightly in frequency from the values in a standard stimulus, and the participants indicated in which observation interval that change occurred.…”