What resolves this contention: Generalizability of the Frank D1/D2 model predic…

What resolves this contention: Generalizability of the Frank D1/D2 model prediction across PD heterogeneity — Brain 2020 contests the universal applicability of the carrot/stick effect. / Levodopa universally reverses Parkinson's negative learning bias to a positive bias across PD patients. / Levodopa enhancement of reinforcement learning is restricted to non-tremor PD subtypes; tremor-dominant patients show no levodopa effect.