Hi
I have an event related design with a cue>outcome design. There are 4 cues and 8 potential outcomes, with the timing between cue and outcome jittered. The task has 4 blocks of 60 trials each. There should be 15 events in each block relating to each cue. The outcomes each have either 10 or 5 events per block (making a total of 60 outcomes per block).
I've entered the onset times into the first level analysis, but the resulting design matrix doesn't appear to have modelled all the events - such that some conditions only have 2 or 3 events per block. Furthermore for two of the conditions in the final block, SPM doesn't seem to be able to find any events at all, and thus registers them as being correlated (see attached .bmp). If I look into the SPM.xX.X matrix this is confirmed, as all the values for these conditions have a value of 0.
I've checked the SPM.Sess structure and the onset times appear to have loaded OK. Does anyone have any ideas why SPM has not been able to model each event? Or does anyone know how I can troubleshoot this problem further?
Thanks
Rob
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