Biological Motion Selective activation of distinct human cortical areas during
discrimination of pattern orientation, non-rigid and rigid motion, and face-gender
categorization. Using fMRI and psychophysics, this study confirms and extends
the previous neurological and neuroimaging findings that different regions in the
human visual cortex are specifically involved in aspects of motion, face, and pattern
perception. Click here for
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Lesions at higher levels in the extrastriate pathway selectively affect the perception
of motion recognition but not low level motion processing. “Biological motion”
was defined by Johansson as the pattern of movement of a small number of lights attached
to the major joints of a human performing simple actions. We studied motion perception
in 20 patients with well documented lesions in either parietal or temporal cortical
areas, who were impaired on biological motion recognition. Interestingly, their performance
on earlier motion tasks such as speed and direction discrimination was normal. They
were impaired, however, on global motion, and on aspects of form perception, including
3DSFM from motion. Two patients, however, performed normally on global motion stimuli
and 3-D structure from motion. We related our results to the physiological findings
that neurons in the rostral part of the superior temporal lobe (STP) respond selectively
to biological motion and to the idea that STP integrates the late stages of the dorsal
and ventral cortical visual streams, thus suggesting that selective lesions in either
stream may impair biological motion perception. We further confirmed this idea in
an fMRI study in normal subjects. Publications 1. Racine C, Vaina LM, Diaz J, Zamani A, Gross CG “Are there specific anatomical correlates of biological perception in the human visual system?”, Soc. Neurosci. Abstr., 1996; 22(1):400. 2. Vaina LM, Belliveau JW, B des Roziers E, Sinha P, O'Craven KM “Selective activation of distinct human cortical areas during discrimination of pattern orientation, non-rigid and rigid motion, and face- gender categorization”NeuroImage , 1997; 5(4):S146. back to Research last update: 12/11/98 |