Hello to all !
I'd like to thank Steve for his very helpful response to my posting about FEAT and the
pre-whitenng step it includes.
There is a couple of other issues I wanted to inquire about.Here they are:
-The FEAT output includes a file called filtered_func_data.hdr.Looking in the
website I see it contains the high-pass filtered data that are then fed into
FEAT.Is there any way of getting the high+low-pass filtered dataset?
-I use a custom made MATLAB routine to save my data as 4-D ANALYZE
datasets for loading into FEAT.In the header, I take care to fill the following
fields:sizeof_hdr,extents=16384,dim,datatype and bitpix.Pixdim I fill in with
ones and the rest is filled in with zeros or spaces.I was wondering if there is any
other piece of information in the header that is used by FEAT to fit a model,and
must therefore be included.
-when it comes to convolving with an HRF model,(egGamma), I suppose the
different parameters(egSTDdev,Meanlag...) are defined essentially by whatever
assumption one makes about the form of the HRF.Nevertheless,does the TR
play any role in making a good guess about these parameters?
Thanks !
Charis.
Charidimos Tzagarakis MD
Brain Sciences Center and University of Minnesota.
Address:
Brain Sciences Center (11B)
Minneapolis VA Medical Center
One Veterans Drive
55417 Minneapolis MN
USA
Tel:612-725-2000 ext 1756
email: [log in to unmask]
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