Thanks Gang -

We are interested in the behavioral effect as we have shown that aged monkeys have increased connectivity with various seed regions involved in learning and memory. This analysis was done with 3dttest++ without covariates but I get similar results with covariates if centered as different. We are unable to compare the 2 aged groups due to lack of statistical power so we wanted to see if functional connectivity varies with behavioral performance across all ages. I realize your new bayesian method might work for these type on analyses (and you had run some analyses for us on a different, even less powered group of animals - in hindsight, I should have given you these datasets instead). At this point, however, we are looking for something simple akin to what was published in Ash et al. (https://www.pnas.org/content/113/43/12286). Here, they also extracted some connectivity data to plot against performance but I am not quite sure how they did that. Any ideas there?

In theory, comparing all of the groups you suggested would be ideal, however, I don't think that is feasible with the number of animals we have. We have done each unimpaired vs. young and impaired vs. young using 3dttest++ without covariates and show different Fc maps when each group is compared to young - I thought this would indicate that significant clusters/regions/activity observed in unimpaired but not impaired might be important for cognition.

Yes - I see a Young_behavior and Aged_behavior. Young_behavior has significant clusters while Aged_behavior does not. Would this indicate then that young animals have increased connectivity between the seed and these positive clusters and that this connectivity is important for cognitive performance? Does this say there is no relationship in aged animals and just young?