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

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

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.