spatio-temporal brain mapping of motion-onset veps combined with fmri and retinotopic maps时空的大脑映射motion-onset veps结合功能磁共振成像和网膜代表地图.pdf

Spatio-Temporal Brain Mapping of Motion-Onset VEPs Combined with fMRI and Retinotopic Maps 1,2 2 1 1 Sabrina Pitzalis , Francesca Strappini , Marco De Gasperis , Alessandro Bultrini , Francesco Di Russo1,2* 1 Department of Education Sciences for Motor Activity and Sport, University of Rome ‘‘Foro Italico’’, Rome, Italy, 2 Neuropsychology Center, Santa Lucia Foundation, IRCCS, Rome, Italy Abstract Neuroimaging studies have identified several motion-sensitive visual areas in the human brain, but the time course of their activation cannot be measured with these techniques. In the present study, we combined electrophysiological and neuroimaging methods (including retinotopic brain mapping) to determine the spatio-temporal profile of motion-onset visual evoked potentials for slow and fast motion stimuli and to localize its neural generators. We found that cortical activity initiates in the primary visual area (V1) for slow stimuli, peaking 100 ms after the onset of motion. Subsequently, activity in the mid-temporal motion-sensitive areas, MT+, peaked at 120 ms, followed by peaks in activity in the more dorsal area, V3A, at 160 ms and the lateral occipital complex at 180 ms. Approximately 250 ms after stimulus onset, activity fast motion stimuli was predominant in area V6 along the parieto-occipital sulcus. Finally, at 350 ms (100 ms after the motion offset) brain activity was visible again in area V1. For fast motion stimuli, the spatio-temporal brain pattern was similar, except that the first activity was detected at 70 ms in area MT+. Comparing functional magnetic resonance data for slow vs. fast motion, we found signs of slow-fast motion stimulus topography along the posterior bra