Psychophysical tuning functions for brief stimuli: preliminary report.
Observations from clinical and research applications of brain stem evoked response audiometry and electrocochleography have suggested that tone bursts of only a few milliseconds' duration can elicit frequency specific responses. Because such brief stimuli are not perceived as being total, the extent to which the auditory system can "tune" to such stimuli was questioned. In order to investigate this question, psychophysical tuning functions were determined for brief tone bursts (i.e., 1. to 2 msec. duration). The results suggest that in working near normal thresholds (and therefore at relatively low sound pressure levels), brief tone bursts do yield rather frequency specific information. However, the range of sound pressure levels of the stimulus for which the tuning is resonably sharp is limited. the tuning functions show signs of deterioration, particularly in the "tip region," with only modest increases in the sound pressure level above threshold (i.e., typically with 20 dB.). Differences also may be seen between tuning functions for these very brief tone bursts, which in turn are characterized by a so-called click pitch, and those of stimuli long enough to have tonal pitch (i.e., 20 msec.). Finally, tuning functions also were examined for click stimulation, which also revealed some degree of tuning at relatively low levels of stimulation.
D000161:Acoustic Stimulation / Q000295:instrumentation / Q000379:methods*; D001299:Audiometry / Q000379:methods*; D001300:Audiometry, Evoked Response / Q000295:instrumentation / Q000379:methods*; D001307:Auditory Perception / Q000502:physiology*; D001933:Brain Stem / Q000502:physiology; D006801:Humans; D011571:Psychoacoustics; D013997:Time Factors