Dear SPMers, I need your help with the interpretation of results of a correlation analysis that I am carrying out between brain metabolism on FDG PET and a cognitive test in a group of patients with dementia
A higher test score indicates better performance
When I set the contrast at 0 0 0 +1 (I have age and sex as covariates) I find no significant cluster
When I set the contrast at 0 0 0 -1 I do find an area of significant (inverse) correlation with the test
Is this an area of hypometabolism, or hypermetabolism, or some kind of artifact?
If it’s hypometabolism, it might might make perfect sense from a cognitive viewpoint… precisely, it might indicate reduced metabolism in an area that physiologically inhibits the cognitive function that my test is measuring (therefore patients with more severe hypometabolism in this area obtain a better score on the test)
Is this reasoning correct?
Thanks a lot for your contribution!
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