Stuart,
You can indeed look at covariates at the second level. Using the basic
models button, choose simple regression(correlation). Enter your scans as
usual, and then enter your covariate when prompted (making sure the order of
the covariate is the same as the order of scans).
Under results weight the covariate column with 1 to see the positive
correlation. Use -1 to see the negative correlation.
Hope this helps.
Sterling C. Johnson, Ph.D.
Neuropsychology Neuroimaging Lab
Barrow Neurological Institute
222 W. Thomas Rd. Ste 315
Phoenix AZ 85013
ph: 602-406-3671
fx: 602-406-6115
email [log in to unmask]
> -----Original Message-----
> From: Dr. Stuart WG Derbyshire [mailto:[log in to unmask]]
> Sent: Wednesday, January 30, 2002 11:01 AM
> To: [log in to unmask]
> Subject: Entering a covariate at the second level
>
>
> I noticed a very similar question (perhaps identical) has been
> posted, so I second the desire for an answer!
>
> We have generated contrast images at the first level and used the
> basic models to examine effects at the second level - no problems.
> But we want to enter a subject covariate (age, depression, whatever)
> at the second level. Can we do this? If we can, how do we do this?
>
> Many thanks,
>
> Stuart.
>
>
> UPMC MR Research Center
> PUH B-804
> 200 Lothrop Street
> Pittsburgh
> PA 15213
>
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