It would be wild if it comes out that not only does he have Parkinson's, but he's using medical marijuana to control his symptoms:

Eight-seven percent of patients (n = 60) were noted to exhibit an improvement in any PD symptom after starting MC. Symptoms with the highest incidence of improvement included cramping/dystonia, pain, spasticity, lack of appetite, dyskinesia, and tremor.

Here's a short video of the effects in action. Night & day difference in <5 minutes.

dementia combined with weed for the Parkinson's and Adderall for focus would be a hell of a cocktail