In order to improve the signal-to-noise ratio,we could filter the raw data.In fNIRS study, sometimes the range of filtering is approximately 0.02-0.08(e.g. some the resting state studies)，but sometimes is approximately 0.02-0.8 （e.g. some cognitive studies ). I want to know what is the rule of  the selection of filtering in fNIRS study.

3Q ^_^