Courtney, if i understand your question, i think one way to do that is to use qdec to draw a label on the blob of interest, and the run 'map label to subjects', which creates a label file in each subjects label dir, then you can run stats on that with mris_anatomical_stats.
(btw, i'm putting this answer on the list, as others may have better ideas.) n. On Mon, 2011-01-03 at 16:38 -0500, Gallen, Courtney (NIH/NIDA) [F] wrote: > Hi Nick > > Thanks for the prompt reply. Sorry if my questions seem a bit naïve--this is > my first time using Freesurfer. > > A follow up question to your answer for question 1. I see that the group data > will be plotted in Qdec for significant blobs, but say there is a significant > interaction between two variables and it's not entirely apparent what is > driving this interaction. > Is there a way to extract the mean of this blob for each individual (i.e., > treat it as an ROI or something similar) to determine what's driving the > significance? > > Thanks in advance! > Courtney > > -----Original Message----- > From: Nick Schmansky [mailto:ni...@nmr.mgh.harvard.edu] > Sent: Thursday, December 30, 2010 2:44 PM > To: Gallen, Courtney (NIH/NIDA) [F] > Cc: freesurfer@nmr.mgh.harvard.edu > Subject: Re: [Freesurfer] Interpreting results from Qdec > > ans. 1. - the easiest way is to Ctrl- left mouse click on a blob, and a > plot of the data at that surface vertex will appear. the group will be > apparent from that (say, demented group is thinner than non-demented > group). this data is significance data (log p, so '2' is 0.01), so mean > and stdev wouldnt apply in that case. the file 'y.mgh' is the raw data > of all subjects in the analysis, so you could extract mean and stdev > from that. > > ans. 2. - slide the 'annotation' opacity slider to show the annotation > data (cortical parcellation). the ctrl left click will also put the > region info for that vertex on the lower left of the display. > > see also: > http://surfer.nmr.mgh.harvard.edu/fswiki/FsTutorial/QdecGroupAnalysis > > n. > > On Wed, 2010-12-29 at 10:49 -0500, Gallen, Courtney (NIH/NIDA) [F] > wrote: > > Hi, > > > > > > > > I’m currently running analyses in Qdec and have identified areas that > > show significant effects in my contrasts. I have two questions related > > to interpreting these results. > > > > > > > > 1. How can you interpret the effect in each “blob?” (i.e., which > > group has a greater cortical surface area, etc.). Right now, all I > > know is that there is an effect in certain areas. Can you export this > > data to get means and standard errors? > > > > 2. Is there a way to localize where these effects are? E.g., a > > tool that tells you this effect is located in __ area of the brain? > > > > > > > > Thanks in advance > > > > Courtney > > > > > > > > Courtney Gallen > > > > Post-baccalaureate IRTA > > > > Neuroimaging Research Branch > > > > National Institute on Drug Abuse (IRP) > > > > 251 Bayview Blvd > > > > Suite 200 > > > > Baltimore, MD 21224 > > > > Tel: (443) 740-2631 > > > > > > _______________________________________________ > > Freesurfer mailing list > > Freesurfer@nmr.mgh.harvard.edu > > https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer > > > > The information in this e-mail is intended only for the person to whom it is > addressed. If you believe this e-mail was sent to you in error and the e-mail > contains patient information, please contact the Partners Compliance HelpLine > at > http://www.partners.org/complianceline . If the e-mail was sent to you in > error > but does not contain patient information, please contact the sender and > properly > dispose of the e-mail. > > _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
