Dear Mayuresh,
I suspect from your description that you are looking for parametric
modulation, eg. a HRF that varies in size with some other response
measure. That is easily implemented in spm5 (when you have a vector of
response measures of the same length as onsets) , i can refer to the
manual that comes with spm5.
[blunt self promiotion] For some examples, see these 2 studies (the 2nd
also used RT), where we used parametric modulation with success
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=Abstract&list_uids=16473025&query_hl=1&itool=pubmed_docsum
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1460-9568.2005.04129.x
[/blunt self promiotion]
Good luck,
Bas
Mayuresh Korgaonkar wrote:
> Hello SPM authors and list,
>
> We have collected event related functional scans for each subject
> along with behavioral measures (RTs) for each event trial. We have 2
> event types: event type A with behavioral measure for each event over
> the entire run and event type B which acts as a control and does not
> have a behavioral measure. There are about 70 event trials of A with
> 70 behavioral measures for each trial. We are basically interested in
> finding functional areas which were activated with increasing RT and
> vice versa.
> I would imagine a correlation analysis would be the way to go about this.
> Reading from the archives, such correlation analyses seem to be done
> at the group level. Is there a way to do this analysis at every
> subject level? How should I procede with this? How would I define my
> contrasts?
>
> Also we are interested in looking at group effects. Would it be valid
> to use the contrast images defined in the single subject level entered
> at the group level? or a separate design would be needed?
>
> I am using SPM2.
>
> Thanks,
> Mayuresh
>
> ------------------------------------------------------------------------
> Want to start your own business? Learn how on Yahoo! Small Business.
> <http://us.rd.yahoo.com/evt=41244/*http://smallbusiness.yahoo.com/r-index>
--
--------------------------------------------------
Dr. S.F.W. Neggers
Division of Brain Research
Rudolf Magnus Institute for Neuroscience
Utrecht University Medical Center
Visiting : Heidelberglaan 100, 3584 CX Utrecht
Room A.00.1.24
Mail : Huispost A.01.126, P.O. Box
3508 GA Utrecht, the Netherlands
Tel : +31 (0)30 2503386
Fax : +31 (0)30 2505443
E-mail : [log in to unmask]
Web : http://www.fmri.nl/people/bas.html
--------------------------------------------------
|