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Perhaps a conjunction analysis? Run your difference that you're interested in and then look at the conjunction with the deactivation contrast. Here's a previous post on conjunction analyses in FSL https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=FSL;e2754da.1105 Cheers, Jeanette On Mon, Apr 16, 2012 at 11:56 AM, Andres Roman <[log in to unmask]> wrote: > Hi Eugene, > > I was wondering then that even if im interested in the differences in > deactivations then still the [1 – 1 ] [-1 1] contrast will give me the > answer? Im trying to look differences in the pattern of deactivations in a > group comparison and im not sure about what contrast to use. > > Best wishes > > -- > *Andres > * > > ------------------------------ > *From: *Eugene Duff <[log in to unmask]> > *Reply-To: *FSL - FMRIB's Software Library <[log in to unmask]> > *Date: *Mon, 16 Apr 2012 17:30:06 +0100 > *To: *<[log in to unmask]> > *Subject: *Re: [FSL] Comparisons of deactivations > > > Hi Andres - > > If the region is deactivating, then a [1 -1] contrast will still identify > regions with greater signal in responses associated with ev 1 - i.e. > reduced deactivation in the ev 1 responses. > > Eugene. > > > > On 16 April 2012 16:39, Andres Roman <[log in to unmask]> wrote: > > I have been doing two groups comparisons and a question came up which I > wasn’t sure how to answer correctly. Usually in the group level I use a [1 > –1] [-1 1] contrast which gives me the directionality of the differences > between groups. My questions is that I am particularly interested in the > differences in the ‘deactivations’ or in other words not the [1 0] contrast > of the first level but rather the [-1 0] contrast. I was wondering if the > directionality is based exclusively on the activation pattern I propose it > to handle? Thank you very much. > > > >