Dear SPMers,
Would anyone know the best way to model 'events' in which 2 stimuli are
presented? This is a fast-paced, event-related fMRI paradigm in which each
3-second trial contains 2 stimuli separated by 1 TR (1.5 sec). Any advice
would be greatly appreciated!
:> Daniel
Daniel Weissman, PhD
Center for Cognitive Neuroscience
Duke University
Durham, NC 27705
phone: (919)-681-1029
fax: (919)-681-0815
e-mail: [log in to unmask]
----- Original Message -----
From: "John Ashburner" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, May 15, 2001 4:56 AM
Subject: Re: sgi, matlab6 and spm99
> I don't know if you are doing the "adjustment" or not. If you are, then
it
> is likely to slow the processing down considerably.
>
> Changing maxMem makes no difference to the realignment. I don't think
that
> increasing swap will have any effect on speed, although it can prevent the
> occasional crash through lack of memory.
>
> Best regards,
> -John
>
> > Hello all,I have set up and compiled spm99 on our sgi o2s with matlab6.
> > We can get things to run, but they are incredibly slow...it can take
4-30
> > hours to do realignment, for example....we are frustrated both by the
> > inconsistencies in time and the length of time it takes to do the
> > processing (the dataset is 264 reps and 19 slices-fMRI).
> >
> > We have fooled with the maxMem variable, and we have increased the swap
> > space to 1gb...given the inconsistencies, it is difficult to determine
if
> > these changes have had any effect....but it looks like our problem
> > persists.
>
> --
> Dr John Ashburner.
> Wellcome Department of Cognitive Neurology.
> 12 Queen Square, London WC1N 3BG, UK.
> tel: +44 (0)20 78337491 or +44 (0)20 78373611 x4381
> fax: +44 (0)20 78131420
> http://www.fil.ion.ucl.ac.uk/~john
> mail: [log in to unmask]
>
>
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