ACTIVATION OF AREA V5 BY VISUAL-PERCEPTION OF MOTION DEMONSTRATED WITH ECHOPLANAR MR-IMAGING

Cortical activation in visual association areas known to be responsibl e for the perception of motion was investigated in two volunteers who viewed a projected animated cartoon periodically ''run'' and ''frozen' ' during collection of echoplanar MR images. Ten axial, contiguous, 5 mm thick, T-2-weighted, gradient-echo images (TE 40 ms, TR 3000 ms) de picting BOLD contrast were acquired through the occipital lobe using a GE Signa 1.5 T system with an advanced NMR operating console. Images were analysed by time series regression modelling estimating power in the MR signal at the ON-OFF frequency of motion. Highly significant ac tivation in response to motion perception was identified in both subje cts bilaterally in area V5.