Perceptual interactions in the loudness of combined auditory and vibrotactile stimuli.
The loudness of auditory (A), tactile (T), and auditory-tactile (A+T) stimuli was measured at supra-threshold levels. Auditory stimuli were pure tones presented binaurally through headphones; tactile stimuli were sinusoids delivered through a single-channel vibrator to the left middle fingertip. All stimuli were presented together with a broadband auditory noise. The A and T stimuli were presented at levels that were matched in loudness to that of the 200-Hz auditory tone at 25 dB sensation level. The 200-Hz auditory tone was then matched in loudness to various combinations of auditory and tactile stimuli (A+T), and purely auditory stimuli (A+A). The results indicate that the matched intensity of the 200-Hz auditory tone is less when the A+T and A+A stimuli are close together in frequency than when they are separated by an octave or more. This suggests that A+T integration may operate in a manner similar to that found in auditory critical band studies, further supporting a strong frequency relationship between the auditory and somatosensory systems.
Research Laboratory of Electronics, Massachusetts Institute of Technology, and Harvard-MIT Division of Health Sciences and Technology, Speech and Hearing Bioscience and Technology Program, Cambridge, Massachusetts 02139, USA.
E Courtenay
EC
Wilson
Louis D
LD
Braida
Charlotte M
CM
Reed
D000161:Acoustic Stimulation; D000222:Adaptation, Physiological; D000293:Adolescent; D000328:Adult; D001301:Audiometry, Pure-Tone; D001306:Auditory Pathways / Q000502:physiology*; D001307:Auditory Perception; D001309:Auditory Threshold; D005260:Female; D005385:Fingers / Q000294:innervation*; D006801:Humans; D008144:Loudness Perception; D008297:Male; D011571:Psychoacoustics; D017603:Signal Detection, Psychological; D014110:Touch; D055698:Touch Perception; D014732:Vibration; D055815:Young Adult