Is the hMT+/V5 Complex in the Human Brain Involved in Stereomotion Perception? An fMRI Study

摘要

Binocular disparity is one of the most powerful sources of depth information. Stereomotion is motion-in-depth generated by disparity changes. This study is focused on the hMT+/V5 complex, which is known to support both motion and disparity processing in primates. Does the motion-complex process Stereomotion as well? BOLD functional magnetic resonance imaging (fMRI) was used. The fMRI contrasts of Stereomotion vs stationary stimuli, as well as lateral non-stereoscopic motion vs stationary stimuli, showed strong fMRI activation of the motion complex. Direct contrasts of Stereomotion vs different types of lateral-motion also revealed differential activity but in a restricted subregion of the motion complex, suggesting a distinct stereomotion-selective neuronal subpopulation within it. No consistent activation was found for the stimuli viewed non-stereoscopically. The stereomotion-specific locus revealed within the hMT+/V5 complex contributes to the understanding of Stereomotion perception and of interactions between motion and stereo mechanisms, as well as to the understanding of the organization of overlapping functionally distinct neuronal subpopulations.