Hi Steve,
Thanks for your answer, it shown me I had some wrong assumptions about
what this timing information was, but I would still need some
clarification about the second part of your answer:
> That's right, to be exact, the exact timing of the positive-going
> zero crossing associated with the event, after HRF convolution.
In my case, the timing value for the first TR for each event can be
either 0, 0.2, 05 or 0.8 TR. There are 6 occurences of each, which
corresponds to the distribution of the oversampling interval across my
trials: 6 trials had either 0, 500, 1000 or 1500ms delay between the
beginning of the TR and the onset of the event. I just don't understand
how the timing information of the raw data text file is related to this
delay. Could you clarify this?
Thanks a lot again, your help is very much appreciated.
Stephane
On Wed, Jan 10, 2007 at 04:49:27PM +0000, Steve Smith wrote:
> Hi,
>
> Some of this is covered in the manual at:
> http://www.fmrib.ox.ac.uk/fsl/feat5/output.html
>
> The order of the rows in a ps_tsplot_zstat*_ev*.txt text file should
> be - for each event (in the order they are entered in the original
> design), a set of rows, one for each TR within the peristimulus
> period following the onset of that event.
>
> That's right, to be exact, the exact timing of the positive-going
> zero crossing associated with the event, after HRF convolution.
>
>
> Cheers, Steve.
>
>
> On 8 Jan 2007, at 19:27, Stephane Jacobs wrote:
>
> >Hi all,
> >
> >I'd like to know how events are ordered in the raw data text file
> >corresponding to the peristimulus plots created by featquery. i.e.,
> >should
> >they be ordered in the same way they occurred and are reported in
> >the Ev
> >file fed into FEAT? Because it's not the case for me...
> >
> >Also, the time indicated in the first column is based on the onset
> >of each
> >event, right? Just to check...
> >
> >Thanks a lot,
> >
> >Stephane
>
>
> ------------------------------------------------------------------------
> ---
> Stephen M. Smith, Professor of Biomedical Engineering
> Associate Director, Oxford University FMRIB Centre
>
> FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
> +44 (0) 1865 222726 (fax 222717)
> [log in to unmask] http://www.fmrib.ox.ac.uk/~steve
> ------------------------------------------------------------------------
> ---
>
|