Selective attention and perceptual learning of speech

Abstract

Phonetic experience can change the perceptual distance between speech sounds, increasing both within-category similarity and between-category distinctiveness. Such warping of perceptual space is frequently characterized in terms of changes in selective attention: Listeners are assumed to attend more strongly to category-differentiating features while ignoring less relevant ones. However, the link between the distribution of selective attention and categorization-related differences in perceptual distance has not been empirically demonstrated. To explore this relationship, listeners were given 6 h of training to categorize sounds according to one of two acoustic features while ignoring the other. The features were voice onset time and onset f0, which are normally correlated and can both serve as a cue to consonant voicing. Before and after training, listener’s performance on a Garner selective attention task was compared with assessment of the perceptual distance between tokens. Results suggest that training can induce both warping of perceptual space and changes in the distribution of selective attention, but the two phenomena are not necessarily related. Results are consistent with a two-stage model of perceptual learning, involving both preattentive adjustment of acoustic cue weighting and higher-level changes in the distribution of selective attention between acoustic cues. [Work supported by NIH-NIDCD 1R03DC006811.]