Dear SPMers (Rik / JB / Christian?)-
are t-testings on the hrf-regressor alone feasible when modelling the
response by the canonical hrf and its temporal derivative? I know that
usually you would recommend F-testing, but in my case the TR is rather short
(~0.32s, at an SOA quite below 2s) when compared to the time constants (p in
spm_hrf ) of the canonical hrf and I think this would give me some
justification for t-testings here. I would prefer modelling the temporal
derivative to account for variance due to different slice timings as well as
to variable hrf-onsets in my particular case. Both the SPM{F} as well as the
SPM{t} I have generated so far make some sense, but the latter are much
better restricted to the areas expected of hosting the activation I am
looking for.
TIA-
Andreas
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