Hi,
I am using a task that involves hearing the same story four times followed by two different tasks. I am attempting to look at habituation effects for the repeated story- so areas where activation decreases as the task is repeated. For this contrast I have conducted an ANOVA. The contrast I specified is:
1 -1 0 0 0 0
0 1 -1 0 0 0
0 0 1 -1 0 0
The problem is when I use this contrast I get one giant whole-brain cluster (figure attached). When I conduct individual t-tests, such as 1 -1 0 0 0 0 or 0 1 -1 0 0 0, I don't see any abnormal activation.
Does anyone know what might be going on here? Also might anyone know a better way of looking at habituation effects?
Thank you,
Meera
Meera Paleja, B.Sc. (Hons.), M.A.
PhD. Student, Psychological Science
Brain Imaging and Memory Lab
Department of Psychology
Ryerson University
Phone: (416) 979-5000 ex. 2192
email: [log in to unmask]
“Perhaps the most fascinating and mysterious universe of all is the one within us.” -- Carl Sagan
|