Laterality differences in speaker and consonant identification in dichotic listening

Abstract

Two dichotic listening experiments assess the lateralization of speaker identification in right-handed native English speakers. Stimuli were tokens of /ba/, /da/, /pa/, and /ta/ pronounced by two male and two female speakers. In Experiment 1, subjects identified either the two consonants in dichotic stimuli spoken by the same person, or identified two speakers in dichotic tokens of the same syllable. In Experiment 2 new subjects identified the two consonants or the two speakers in pairs in which both consonant and speaker distinguished the pair members. Both experiments yielded significant right-ear advantages for consonant identification and nonsignificant ear differences for speaker identification. Fewer errors were made for speaker judgments than for consonant judgments, and for speaker judgments for pairs in which the speakers were of the same sex than for pairs in which speaker sex differed. It is concluded that, as in vowel identification, neither hemisphere clearly dominates in dichotic speaker identification, perhaps because of minor information loss in the ipsilateral pathways.