Feeling Sound (360G-Wellcome-207038_Z_17_Z)

This proposal addresses fundamental questions about the basis of multisensory integration for touch and hearing in humans. Previous psychophysical studies in the supervisor’s lab have demonstrated interactions between amplitude-modulated sound and visual stimuli. Specifically, the ability of subjects to discriminate the amplitude-modulation depth in sounds is influenced by simultaneously watching a video of a shape expanding and contracting at the same rate as the sound modulation. The aim of the current study is to test the hypothesis that a similar multisensory interaction occurs between sound and tactile stimuli. Subjects will discriminate the depth of amplitude modulated tones (carrier frequency 250 Hz; modulation rate 2 Hz). In some cases these sound stimuli will be accompanied by a tactile stimulus in the form of a vibration delivered to the index finger with the same (2 Hz) or different (1Hz) frequency of modulation as the sound stimulus. By determining psychophysical thresholds for the sound discrimination under different conditions we will establish whether the tactile stimulus enhances or diminishes the perceived sound modulation. A second experiment will address the reverse condition, namely does sound influence tactile discrimination. The project is an ideal vacation project, because it provides the student with an independent, self-contained project.