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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Matthew
August 14, 2007 12:27PM
Hi Afni users,

I have, what I think, is a quick question.

I am using the stim_times option with a TENT function of (0, 14, 8) (my TR=2). I have 9 different stimulus types. There are three runs.

I seem to be having a bit of a problem wrapping my head around how to develop my GLT files.

For my GLT files, I believe I need 7 regressors (1 TR = 1 lag = 2 seconds; 14/2 = 7 regressors). So if i wanted to compare stim types 1 and 2 the GLT file should be as so?

0000001111111-1-1-1-1-1-1-100000000000000000000000000000000000000000000000000000000

My confusion is from an example in the course notes posted on the web. The example used the same TENT function, but said this example had "8 beta coefficients for each stimulus class..."

So should I be using 7 or 8?

Also, on a side note: in the example on the web, it mentioned you can add up just the #2,3,4,5,&6 beta weights for one stimulus type... I'm slightly confused at when this is useful?

Thanks!

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Subject Author Posted

quick question: GLT using TENT function

Matthew August 14, 2007 12:27PM

Re: quick question: GLT using TENT function

Gang Chen August 14, 2007 12:53PM