My impression is that the band of interest is 0 - 0.01 Hz, although this does
not seem to be an absolute rule. Check out the Biswal paper, and also these:
Achard S, Salvador R, Whitcher B, Suckling J, Bullmore E. A resilient, low-
frequency, small-world human brain functional network with highly connected
association cortical hubs. J Neurosci. 2006 26(1):63-72.
Cordes D, Haughton VM, Arfanakis K, Carew JD, Turski PA, Moritz CH, Quigley
MA, Meyerand ME. Frequencies contributing to functional connectivity in the
cerebral cortex in "resting-state" data. AJNR Am J Neuroradiol. 2001
22(7):1326-33.
Two reasons to be suspicious of higher frequencies are (1) the low sampling
rate of fMRI and (2) physiologic breathing artifact can be as low as 0.3 Hz.
As Stephen Smith mentioned, lowpass filtering is not necessarily the best way
to enforce this frequency band.
On Monday, March 19, 2012 12:07:49 you wrote:
> Hello all,
> I know this is a simple question, which I should know the answer to
> but I am going to put it out there.
>
> Can someone tell me why the study of the resting state temporally
> filters the data to only those frequencies between ~0.01 Hz and 0.08
> Hz?
>
> I know that this was done in Biswal et al. 1995, but I am not clear on
> what the motivation is for this choice.
>
> If someone can point me to papers that I must have missed that would be
> great.
>
> Thank you,
> Jason.
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