Hi,
in a recent answer to a question concerning event-related fMRI in SPM99
Karl stated:
> Current thinking, in event-related fMRI, suggests
> that rapid presentation is much more efficient. Inter-trial intervals
> (or SOAs) of 1 to 4 seconds are now common. You do not have to worry
> about the responses overlapping each other because (under a linear
> model) they can be separated.
Is it true that when using short SOAs I have to choose 'Interaction
among trials (Volterra )' - YES, because otherwise SPM does not acount
for short presentation rates at all ?
How short can the SOA reasonably be ?
Thanks for your comments,
Susanne
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Dipl. Math. Susanne Weis
IZKF-ZNS, Dept. for Neuroradiology
University of Technology RWTH Aachen
Pauwelstrasse 30, D-52057 Aachen
Tel: +49-241-80-88890 Fax: -88-88440
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