ASA 127th Meeting M.I.T. 1994 June 6-10

4pSP31. Perception of linear formant trajectories in vowels.

Dept. of Audiol. & Speech Pathology, The Univ. of Tennessee, Knoxville, TN 3796-0740

Boundary locations for identification functions were tested for /(small capital eye)-|oh/ and /(small capital you)-(small capital eye)/ continua. In the /(small capital eye)-|oh/ continuum, F1 varied in 14 steps from 360 to 580 Hz, and in the /(small capital you)-(small capital eye)/ continuum, F2 varied in 19 steps from 1000 to 2000 Hz. There were five different types of stimuli in each continuum with (1) steady-state formants, (2) one formant changing linearly over time, and (3) two formants changing linearly. The single changing formant was F1 in the /(small capital eye)--|oh/ continuum and F2 in the /(small capital you)--(small capital eye)/ continuum. The two changing formants were F1 and F2 in both continua. The trajectories had upward or downward directions. Identification functions were obtained with ten normal-hearing subjects. Directions of boundary shifts for the /(small capital eye)--|oh/ continuum indicated a perceptual emphasis of the initial segments of F1 and F2 trajectories. The directions of boundary shifts for the /(small capital you)--(small capital eye)/ continuum indicated a perceptual emphasis of the final segment of F2 trajectory when only F2 changed over time. However, when changes over time in F1 were added, boundaries for these stimuli were not significantly different from the boundary for the stimuli with steady-state formants. Differences in perception of F1 and F2 trajectories in two tested continua will be discussed. [Work supported by NIH.]