Elicitation of the acoustic reflex with synthetically produced consonant and vowel stimuli.

Acoustic reflexes were elicited from seven normal hearing subjects with synthesized isolated consonant and vowel speech stimuli. Stimulus intensity and duration were controlled so that equivalent amplitudes and durations from 100 to 300 msec were produced. The recorded stimulus items were presented over an earphone to the subject's right ear, while susceptance changes caused by bilateral acoustic reflex activity were monitored in the subject's left ear. Analysis of variance revealed no significant difference between reflex threshold values for isolated synthetic consonant and vowel stimuli. Main effects of stimulus duration and subjects and the two-way interaction of phoneme type by subject were found to be significant.