You need to include some time for fixation. Ie, your total run time is 180*2=360 sec. The total stimulation time is 12*10*3 = 360 sec. You need to increase the length of the fmRI run (or reduce the total number of stimuli). Usually I include as much fixation as any other condition. In this case, that would be 12*10=120 sec. So try adding 120 sec (ie, incrase --ntp 180) and re-run
On 12/19/2017 05:21 PM, Dirks, Bryce Ronald Alan wrote:
Hello,
I am trying to create the optseq for a cognitive flexibility experiment we are conducting. It consists of 10 flexibility, 10 control, and 10 fixation trials. The flexibility and control trials are 12 seconds long. Our TR= 2s. We want to ensure our trial onsets are not time-locked to our TR. We are also unsure how long our response window should be given our rather long trial duration (12s). The code below is what I have made to try to do this and I keep getting that the schedules were ill-conditioned. Any information on how to resolve this error is appreciated!
/./optseq2 --ntp 180 --tr 2 --psdwin 0 30 1 --ev flexibility 12 10 --ev control 12 10 --nsearch 10000 --nkeep 3 --o cFIST_10trials8s_Run1/
//
Thank you,
*Bryce Dirks* Research Associate Brain Connectivity and Cognition Laboratory Department of Psychology University of Miami Website: http://www.psy.miami.edu/bccl/ Phone:_ (305)284-3286_
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