ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

5pSC24. Does the perceptual magnet effect hold for the [(small capital eye)] category?

Joan E. Sussman

Dept. of Commun. Disord. and Sci., State Univ. of New York at Buffalo, 122 Park Hall, Buffalo, NY 14260

Brian S. Gekas

SUNY at Buffalo, Buffalo, NY 14260

Recent speech perception investigations [J. E. Sussman and V. J. Lauckner-Morano, 539--562 (1995); P. Iverson and P. K. Kuhl, 563--572 (1995)] support a ``perceptual magnet effect'' [P. K. Kuhl, Percept. Psychophys. 50, 93--107 (1991)], i.e., poor discrimination around a best exemplar compared with discrimination around a poor example of the category. To date, the magnet effect has been observed using the vowel [i] or consonant categories. A magnet effect might be expected because a range of good [i] tokens around a ``best'' exemplar would exist. However, a magnet effect may not occur for vowels with smaller and more variable categories. Each of 10 listeners rated [(small capital eye)b] stimuli as the [(small capital eye)] in ``bib'' or not the [(small capital eye)] in ``bib.'' Then, each listener heard the tokens he/she had labeled as [(small capital eye)] at least 50% of the time and chose a ``best [(small capital eye)].'' Results show that [(small capital eye)] has a smaller range (45--60 mels) around a best exemplar than [i]. Subjects chose different tokens as their ``best'' exemplar and varied in the number of tokens located in their [(small capital eye)] categories. Finally, results were compared to two sessions of a Change/No-change discrimination task: One with the ``best [(small capital eye)]'' s the fixed standard, the other with a poorer example of [(small capital eye)] as the fixed standard for measurement of a magnet effect.