Joan M. Sinnott
Comparative Hearing Lab, Psych. Dept., Univ. So. Alabama, Mobile, AL 36688
Melissa A. Borneman
Paul A. Dagenais
Univ. So. Alabama, Mobile, AL 36688
Humans and monkeys were compared in their perception of phoneme boundary shifts along two synthetic syllable--final stop--glide /b(open aye)b/--b(open aye)U/ continua differing in overall syllable duration (150 vs 320 ms). Humans were first tested with a written identification procedure and showed a boundary shift to longer transition durations with increased syllable duration, as previously reported in the literature for syllable--initial stop--glide /b(open aye)--w(open aye)/ data. Humans and monkeys were then tested with a low-uncertainty discrimination procedure but showed little evidence of a sensory-level discontinuity underlying the identified boundaries: Instead sensitivity appeared to follow Weber's law. Finally, both human and monkeys were tested with a go/no-go identification procedure specifically designed for monkeys. Both species clearly showed the shift effect, but quantitative differences emerged between the species that were generally consistent with comparative psychoacoustic measures of temporal discrimination. [Work supported by NIDCD.]