Re: [Freesurfer] opseq2 efficiency vs VRF

2010-04-22 Thread Douglas N Greve
First of all, the number of stimuli should not influence the estimate of the % change, only its variance (ie, it won't bias you to find a change that is not there). Having said that, you can get some non-linearities if stimuli are too close to each other, so you'll want to make sure to check th

[Freesurfer] opseq2 efficiency vs VRF

2010-04-22 Thread raij
Hi Doug and other Freesurfers, We are trying to balance the power of different event-related fMRI runs (each consisting of a different experimental condition with different interstimulus intervals) using the optseq2 definition for efficiency. Our outcome metric is the BOLD % signal change amplitu