You created the analysis by specifying all the parameters needed to analyze the data. Now, using selxavg-sess, the actual analysis takes place. This program separately analyzes the data in each session indicated in the sessid file, then computes the average signal intensity maps for each condition. This average data can be further processed on an individual basis and/or can be used for group analyses.

Note: The -fsd flag specifies the functional subdirectory when you make the analysis, and is not needed in this step. In your Study Directory, run “selxavg-sess” with all the following options:

-analysis analysisname
-sf sessid
-df sesspar

Example:

selxavg-sess -sf sessid -df sesspar -analysis sem_assoc

OUTPUT: This will create a subdirectory with the same name as your “analysisname” (e.g. sem_assoc) under the bold directory . There will be two volumes in this directory, one with stem “h” and one with stem “h-offset”. These are where the hemodynamic averages are stored, i.e.:

h: contains the estimated hemodynamic response at each voxel, along with the standard deviation of the residual error. h-offset: contains a map of the mean value at each voxel.

There is also a text file called h.dat with information about the parameters used during the analysis. Future processing of this analysis will create other subdirectories under “analysisname”.

FsFastTutorialV4.5/905_Average_session-level_data_by_condition (last edited 2011-05-19 15:29:07 by NickSchmansky)