Hello,
When modelling the serial correlations with an AR model for the noise in
fMRI, it is usually assumed that the maximum model order is about 5 (e.g.
Penny et al. NI 2003). However, the same references use acquisition times
(TR) values of approximately 2s.
Does anybody know if this value is also valid for very short TRs, e.g. less
than 0.5s?
Thanks in advance,
Cesar
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