Hi Monty,
I'm not sure about including voxel-wise EVs, but I would suggest including the mean of the values in your subject.feat/mc/prefiltered_func_data_mcf_rel.rms files. Assuming you've "scrubbed" out bad volumes with fsl_motion_outliers, you could ignore the "deleted" indices when computing the mean of the relative motion file. This approach won't completely eliminate head motion between groups, but it will at least give you a covariate that helps control for the group differences.
Cheers,
David
> On Mar 13, 2015, at 9:12 AM, Harms, Michael <[log in to unmask]> wrote:
>
> Hi,
> To chime in again here, while including motion parameters as regressors
> does help to some degree, it is not sufficient to eliminate differences
> between groups based on motion.
>
> cheers,
> -MH
>
> --
> Michael Harms, Ph.D.
>
> -----------------------------------------------------------
> Conte Center for the Neuroscience of Mental Disorders
> Washington University School of Medicine
> Department of Psychiatry, Box 8134
> 660 South Euclid Ave. Tel: 314-747-6173
> St. Louis, MO 63110 Email: [log in to unmask]
>
>
>
>
> On 3/13/15 7:44 AM, "Monty Waite" <[log in to unmask]> wrote:
>
> Thanks Eduardo
> What I have is a set of resting fMRI data between patient and control
> I have run a dual regression and randomise between the two groups
> (unpaired t test) and that has shown altered connectivity between the
> groups
> What I would like to be able to show is that this is unlikely to be a
> cause of increased head motion between the groups
>
> If I look at the absolute RMS values for the two groups, there is a
> difference suggesting that the patients were moving more in the scanner
> (no surprise)
>
> How can I add the MCFLIRT outputs to randomise as a voxel specific EV??
>
> Thanking you as always
>
> Monty
>
>
> ________________________________
> The materials in this message are private and may contain Protected Healthcare Information or other information of a sensitive nature. If you are not the intended recipient, be advised that any unauthorized use, disclosure, copying or the taking of any action in reliance on the contents of this information is strictly prohibited. If you have received this email in error, please immediately notify the sender via telephone or return mail.
|