abstract  background: the brain response to temporal frequencies (tf) has been already reported, but with no study reported for different tf with respect to various spatial frequencies (sf).  materials and methods: fmri was performed by 1.5t ge-system in 14 volunteers during checkerboard, with tfs of 4, 6, 8 and 10hz in low and high sfs of 0.5 and 8cpd.  results: average percentage bold signal ...

PURPOSE This study examined the number and nature of spatiotemporal channels in the region where the frequency-doubling (FD) illusion would be expected to occur at eight locations spanning the central 30 degrees of the visual field. METHODS The probability of seeing the FD illusion was examined in 17 subjects. Stimuli were presented at 5 octaves of low spatial frequencies, at each of seven fl...

A popular model of visual perception states that coarse information (carried by low spatial frequencies) along the dorsal stream is rapidly transmitted to prefrontal and medial temporal areas, activating contextual information from memory, which can in turn constrain detailed input carried by high spatial frequencies arriving at a slower rate along the ventral visual stream, thus facilitating t...