Common neural processing regions for dynamic and static stereopsis in human parieto-occipital cortices.

We performed functional magnetic resonance imaging to identify the neural processing regions in the parieto-occipital cortices for human dynamic and static stereopsis. The subjects were ten ophthalmologists professionally trained to do microscopic surgery. Visual stimuli for dynamic or static stereopsis were performed with solid stereograms displayed in the image guides of a binocular visual stimulation device that we developed. The dorsal occipital portion and the superior parietal lobule (i.e. dorsal parieto-occipital portion) were activated not only in static stereopsis, but also in dynamic stereopsis. The activation showed a right hemispherical dominancy. On the other hand, the temporo-occipital junction (i.e. human MT (middle temporal area) / MST (medial superior temporal area) complex) was activated in dynamic stereopsis. This demonstrates that the dorsal parieto-occipital portion is a common neural processing region for dynamic and static stereopsis.