title: Contingent categorization in speech perception.
abstract: The speech signal is notoriously variable, with the same phoneme realized differently depending on factors like talker and phonetic context. Variance in the speech signal has led to a proliferation of theories of how listeners recognize speech. A promising approach, supported by computational modeling studies, is contingent categorization, wherein incoming acoustic cues are computed relative to expectations. We tested contingent encoding empirically. Listeners were asked to categorize fricatives in CV syllables constructed by splicing the fricative from one CV syllable with the vowel from another CV syllable. The two spliced syllables always contained the same fricative, providing consistent bottom-up cues; however on some trials, the vowel and/or talker mismatched between these syllables, giving conflicting contextual information. Listeners were less accurate and slower at identifying the fricatives in mismatching splices. This suggests that listeners rely on context information beyond bottom-up acoustic cues during speech perception, providing support for contingent categorization.
authors.affiliation: Dept. of Psychology, University of Iowa, E11 SSH, Iowa City, IA 52242, (319)335-0692.
authors.forename: Keith S
authors.initials: KS
authors.lastname: Apfelbaum
authors.affiliation: Dept. of Psychology, University of Iowa, E11 SSH, Iowa City, IA 52242, (319)335-0692.
authors.forename: Natasha
authors.initials: N
authors.lastname: Bullock-Rest
authors.affiliation: Dept. of Neurosurgery, University of Iowa, 1825 JPP, Iowa City, IA 52242, (319)335-7049.
authors.forename: Ariane E
authors.initials: AE
authors.lastname: Rhone
authors.affiliation: Dept. of Linguistics, University of Kansas, 1541 Lilac Ln., Lawrence, KS 66044, (785)864-2384.
authors.forename: Allard
authors.initials: A
authors.lastname: Jongman
authors.affiliation: Dept. of Psychology, Dept. of Communication Sciences and Disorders and Delta Center, University of Iowa, E11 SSH, Iowa City, IA 52242, (319)335-2408.
authors.forename: Bob
authors.initials: B
authors.lastname: McMurray
keywords: contingent categorization; expectation; fricatives; speech perception