There is not a hard and fast formula. With a block length of 16 sec, you will have frequencies at 0.0625Hz and multiples thereof. The closer you are to 0.625, the more signal you are going to lose. Also, if you don't remove the whitening, then FSFAST will compute a highpass filter for you. I think that .01Hz is probably fine, but you could bump it up to .02Hz too
On 8/6/2020 6:11 PM, Nasiriavanaki, Zahra wrote:
Hi Freesurferers
Could you please let me know how I should calculate the high pass filter cutoff? I have seen a bunch of different formulas (i.e 1.5*the stimulation period)? My task is a block-designed task, each stimuli takes 16 seconds and is followed by the next stimuli without an ITI. TR=2, number of conditions=8. I have used a hpf=0.01, Is this correct?
Thanks Mona
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