Hi Doug,

the p-values are all much lower when I combine both the counterclockwise and clockwise stimuli and the angle maps look completely different.
I have noticed that for the eccentricity data I have the same problem (contracting and expanding rings).

Below you can find the images (it is macaque MION fMRI data).




Thanks,

Thomas

On 06 Aug 2012, at 19:43, Douglas N Greve wrote:

what is it that is noisy? The angle map or the p-value map? Can you send
pics?
doug

On 08/06/2012 12:41 PM, Thomas Janssens wrote:
Hi,

I am currently analyzing some retinotopy data.
For the polar angle stimulus we had both clockwise and counterclockwise stimuli.
Both of them started at the top of the screen (12 o'clock), each run includes 4 full cycles and ends with the last wedge slightly before/after 12o'clock.

We have created seperate paradigm files (direction pos /  direction neg) for the clockwise and counterclockwise runs and followed the steps as indicated by the "FsFastIndividualRetinotopyAnalysis".
However, when we run the Freesurfer retinotopy analysis on the whole data set, the polar angle is very noisy.
When we run the same analysis separately for the clockwise and counterclockwise runs separately, the results look much better.
Could anyone tell me what I am doing wrong?

Thanks!

Thomas





_______________________________________________
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer



--
Douglas N. Greve, Ph.D.
MGH-NMR Center
greve@nmr.mgh.harvard.edu
Phone Number: 617-724-2358
Fax: 617-726-7422

Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting
FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html

_______________________________________________
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer



Thomas Janssens, PhD student FWO
Laboratorium voor Neuro- en Psychofysiologie
K.U.Leuven Medical School
Herestraat 49, B-3000 Leuven (Belgium)
phone +32 16 33 00 35
cell phone +32 494 115 509
thomasj@nmr.mgh.harvard.edu
thomas.janssens@med.kuleuven.be