We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:
https://discuss.afni.nimh.nih.gov
Existing user accounts have been migrated, so returning users can login by requesting a password reset. New users can create accounts, as well, through a standard account creation process. Please note that these setup emails might initially go to spam folders (esp. for NIH users!), so please check those locations in the beginning.
The current Message Board discussion threads have been migrated to the new framework. The current Message Board will remain visible, but read-only, for a little while.
I'm not so sure what you mean by 'higher activation': higher beta value or t-statistic? Generally speaking, with a bigger sample size (number of trials or subjects), you would get more reliable results, but the effect estimates would remain unbiased. In other words, more trials should lead to little changes in the effect estimates (beta values), but the t-statistic values might be higher. Is this consistent with your observation?