I am planning to do an fMRI study in depression. Previously, power calculation was not commonly done for fMRI studies but recently it seems to have become a prerequisite for grant applications. I would greatly appreciate your views on this.
Please see Mumford & Nichols (2008). Power calculation for group fMRI studies accounting for arbitrary design and temporal autocorrelation. http://www.sciencedirect.com/science/article/pii/S1053811907007100
And their sofrware fmripower: http://fmripower.org/index.html