Ten patients with Parkinson’s disease were examined using a procedural learning task and Sternberg’s declarative short term memory test, under two condition’s: on dopaminergic medication producing an optimal motor state, and without medication. The performance in the non-declarative task was improved, while reaction times in the declarative memory test were delayed in medicated subjects. The findings lead to the conclusion that dopaminergic medication can impair declarative short-term memory even in doses producing motor improvement.

        Key words: Parkinson’s disease, declarative short-term memory, procedural learning, dopamine, dopa- minergic medication