an fmri study of human visual cortex in response to spatiotemporal properties of visual stimuli
نویسندگان
چکیده
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 change demonstrated the amplitude of the fmri response to different tfs was maximal in 6hz for high sf of 8cpd, while, it was maximal at tf of 8hz for low sf of 0.5cpd. conclusion: the results are useful for vision therapy (such as the treatment of amblyopia) and visual task selecting in fmri studies.
منابع مشابه
An fMRI study of human visual cortex in response to spatiotemporal properties of visual stimuli
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 signa...
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عنوان ژورنال:
iranian journal of radiation researchجلد ۳، شماره ۴، صفحات ۱۹۱-۱۹۴
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