Percent Signal Change for fMRI
نویسنده
چکیده
Quantitative scaling into percent signal change is helpful to detect and eliminate “bad” results with abnormal extreme values. While cognitive effects give signal changes on the order of 1% (and larger in the visual and auditory cortices), signal variations of over 10% may arise from motion and other artifacts in the data. Thus, a quantitative check on measured effect size can be used to screen abnormally large values likely caused by artifacts in the data.
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