AFNI Message Board

Dear AFNI users-

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.

Sincerely, AFNI HQ

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Donald McLaren
January 17, 2005 01:01PM
Does anyone have a method for deciding whether a BOLD response is positive or negative in an Event-related design? I've narrowed it down to two possible equations in my mind, but I am open to others.

Equation 1: Positive response is when the sum of all IRF coefficents is greater than 0; Negative response is when the sum of all IRF coefficents is less than 0.

Equation 2: Postive response is when the sum of all IRF coefficents (when each coefficent has the average of the first and last coefficent subtracted out); negative response is when that sum is neagtive.

Any thoughts would be appreciated.
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postive versus negative responses

Donald McLaren January 17, 2005 01:01PM