Influence of Visual Motion on Tactile Motion Perception

• Published in: Journal of neurophysiology 2006-09, Vol.96 (3), p.1625-1637
• Main Authors: Bensmaia, S. J, Killebrew, J. H, Craig, J. C
• Format: Article
• Language: English
• Subjects: Female; Humans; Male; Motion Perception - physiology; Motor Activity; Movement - physiology; Photic Stimulation; Physical Stimulation; Touch - physiology
• ISSN: 0022-3077; 1522-1598
• DOI: 10.1152/jn.00192.2006

1 Department of Neuroscience and 2 Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, Maryland; and 3 Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana Submitted 21 February 2006; accepted in final form 16 May 2006 Subjects were presented with pairs of tactile drifting sinusoids and made speed discrimination judgments. On some trials, a visual drifting sinusoid, which subjects were instructed to ignore, was presented simultaneously with one of the two tactile stimuli. When the visual and tactile gratings drifted in the same direction (i.e., from left to right), the visual distractors were found to increase the perceived speed of the tactile gratings. The effect of the visual distractors was proportional to their temporal frequency but not to their perceived speed. When the visual and tactile gratings drifted in opposite directions, the distracting effect of the visual distractors was either substantially reduced or, in some cases, reversed (i.e., the distractors slowed the perceived speed of the tactile gratings). This result suggests that the observed visual-tactile interaction is dependent on motion and not simply on the oscillations inherent in drifting sinusoids. Finally, we find that disrupting the temporal synchrony between the visual and tactile stimuli eliminates the distracting effect of the visual stimulus. We interpret this latter finding as evidence that the observed visual-tactile interaction operates at the sensory level and does not simply reflect a response bias. Address for reprint requests and other correspondence: S. J. Bensmaïa, Krieger Mind/Brain Institute, 338 Krieger Hall, 3400 N. Charles St., Baltimore, MD 21218 (E-mail: sliman{at}jhu.edu )