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Dear SPMers, I am new to MEG analysis and SPM. That said, I have run into an issue with my between-group analysis. I have 2 groups (19 participants in each; healthy, clinical) and 2 conditions of interest (35-41 trials in each; control, experimental). I started out with a full factorial design including groups and conditions as factors, each with 2 levels (in Specify 2nd-level batch). In between group comparisons for clinical>healthy contrast in both control and experimental conditions, I found highly significant activations in bilateral ventral temporal and orbitofrontal areas across all time windows of interest (50-450ms after stimulus onset). The activations in healthy>clinical contrast for both conditions comprised entirely distinct set of areas, involving superior parietal, pre and post central gyri and subcortical areas throughout all time windows of interest. I re-ran these analyses using two-sample t-tests per condition and found the same sustained activations. Next, I tried within-group, paired t-tests to contrast between conditions in each group separately. This resulted in significant activations in the areas that we had expected and temporal pattern of activation in different time windows also makes sense. Any ideas as to what's going on in my between-group analyses? I can provide more details regarding my groups and conditions/task and screenshots of my SPM results, if needed. Thanks, Priyanka ________________________________ This e-mail may contain confidential, personal and/or health information(information which may be subject to legal restrictions on use, retention and/or disclosure) for the sole use of the intended recipient. Any review or distribution by anyone other than the person for whom it was originally intended is strictly prohibited. If you have received this e-mail in error, please contact the sender and delete all copies.