Cognitive impairments in early Parkinson\u27s disease are known to be linked to complex changes in the dopamine system within the brain. For example, dopamine-producing neurons in one key region of the brain are significantly degenerated, but those in another are spared. Dopamine-replacement therapy (DRT) has been pursued and it has produced significant improvements in certain cognitive functions - unfortunately it also produced significant impairments in others.https://ir.lib.uwo.ca/brainscanprojectsummaries/1019/thumbnail.jp
