code/analysis for population coding / behavior portion of svd R01 renewal

SVD requests:

• TBP invariance: active vs. passive d’ for ref-ref/tar-tar/ref-tar A1 vs. PEG
• TBP breakdown of 1st vs. 2nd order contributions to delta dprime. (ref vs. tar only?). Do the other tasks show the same effects (PTD, BVT)? If so, maybe include them in the same plot with diff color?
• Behavior performance vs. ref-tar D’ — for all data? (PTD, TBP, BVT) assuming they all show the same trend
• BVT: invariance analysis. I know it’s only A1, which is find. the point is (I think) that we don’t see evidence for invariance