Perceptual Dimensions of Nonnative Speech

Foreign-accented speech has most commonly been characterized across three related, but independent dimensions: intelligibility, comprehensibility, and accent [6]. The present study applied an auditory free classification task, which has been used to test listeners’ perceptual representations of regional dialects [5] and different languages [3], to further investigate the salient perceptual dimensions of foreign-accented speech. Participants first rated recordings of 24 nonnative speakers for comprehensibility and degree of accent. The speakers’ intelligibility was measured in a separate study. These three dimensions were significantly correlated; comprehensibility and degree of accent were the most highly correlated. Multidimensional scaling analyses of the auditory free classification data revealed two dimensions of perceptual salience: gender and degree of accent. The current results, together with previous findings [3, 5], suggest that listeners’ perceptual representation of speech variability centrally involve a scaling of the distance between a speech stimulus and the listener’s own linguistic system.