Oh, Sorry, it chould probably have been .0313Hz. Assuming that it is 16 sec on and 16 sec off, then the period is 32 sec. 1/32sec = .0313Hz
On 8/7/2020 11:29 AM, Nasiriavanaki, Zahra wrote: > Could you please explain how you came up with “0.0625 Hz”? > You mentioned in your first email: “With a block length of 16 sec, you will > have frequencies at 0.0625Hz and multiples thereof.” > > Thanks > Mona > >> On Aug 7, 2020, at 10:42 AM, Douglas N. Greve <dgr...@mgh.harvard.edu> wrote: >> >> Sorry, I don't have a paper on it >> >> On 8/7/2020 10:27 AM, Nasiriavanaki, Zahra wrote: >>> Hi Doug >>> >>> Thanks so much for your reply. This is a question that a reviewer has >>> pointed out. They were concerned that with the stimuli duration of 16 sec, >>> maybe I am not using the correct hpf cutoff. >>> Could you please refer me a paper about this? >>> >>> Thanks >>> Mona >>> >>> >>>> On Aug 7, 2020, at 10:15 AM, Douglas N. Greve <dgr...@mgh.harvard.edu> >>>> wrote: >>>> >>>> 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 >>>>> >>>>> >>>>> _______________________________________________ >>>>> Freesurfer mailing list >>>>> Freesurfer@nmr.mgh.harvard.edu >>>>> https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer >>>> _______________________________________________ >>>> Freesurfer mailing list >>>> Freesurfer@nmr.mgh.harvard.edu >>>> https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer >>> _______________________________________________ >>> Freesurfer mailing list >>> Freesurfer@nmr.mgh.harvard.edu >>> https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer >> _______________________________________________ >> Freesurfer mailing list >> Freesurfer@nmr.mgh.harvard.edu >> https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer > > _______________________________________________ > Freesurfer mailing list > Freesurfer@nmr.mgh.harvard.edu > https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
