Dear all:
Before asking my question I would simply like to describe the
experimental paradigm:
- Each run within the experiment contained 3 randomly presented
event types or conditions (A, B and C)
- Each event type or condition was presented every 13 sec (stimulus
duration was 2 sec and ISI was 11)
- TR for the experiment was 3.25 sec
- 160 volumes were acquired during the run, but because of buffer
size problem, every 4th volume was discarded after acquisition, leaving only
120 volumes.
Now the original authors (this experiment was performed by another
lab within our institution, so I do not quite have all the details) would
like to analyze the data using an event-related approach, but I advised them
that this would be problematic because of the missing data points. My
question is simple, how would one properly handle the data? Were guessing
setting it up as a box car model and then using random effects analysis (20
subjects were scanned). Any comments or suggestions, as always, are greatly
appreciated.
Walter S. Marcantoni
Centre de Neuroscience de la Cognition
Université du Québec à Montréal
Montreal, Canada
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