thanks Jon,
i didn't know that a simple block design analysis is possible to compute
the visual area boundaries...
(which is the reason why I tried to fit it into the standard sfa-sess
analysis)...
could you explain me (shortly) what to do than with my data
regards,
Lars.
-design info: 8hz flickering checkerbords, 20 scans at horizontal
meridian, 20 scans vertical..x10 repetitions...
Jonathan Polimeni schrieb:
hi lars,
the FSFast retinotopy analysis stream is geared towards temporal phase
encoded data analysis, which produces field sign maps that can be used to
define area boundaries.
if you opt to use stationary wedge stimuli to activate the horizontal and
vertical meridian representations in visual cortex rather than the
traditional phase encoding stimulus paradigm, since the vertical and
horizontal meridian representations also lie along area boundaries, you
can identify them in your data through a standard block design paradigm
analysis. this is straightforward but outside the retinotopy stream.
instead you can use 'mkanalysis-sess' and 'selxavg3-sess' as described on
the fswiki.
of course it is possible to interpret your periodic stimulus as temporally
phase encoded and run the usual frequency analysis (i.e., 'sfa-sess'), but
i think that the block design analysis is more appropriate for your data.
hope this helps!
-jon
Lars Kuchinke, PhD
Freie Universität Berlin
Allgemeine Psychologie
Habelschwerdter Allee 45
14195 Berlin
[EMAIL PROTECTED]
www.fu-berlin.de/allgpsy
Tel: 030 838 55776
___
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
