Relive the knowledge:
Parkinson's disease（Parkinson’s disease (PD) patients, the largest feature occurs when the EPS（Extrapyramidal Syndromes, or called extrapyramidal symptoms, which factor is the brain neurotransmitter of the proportion of abnormalities in 5－HT increase or Dopamine to reduce in order to make the brain 5-HT and Dopamine relative proportions of change and emergence, but to note the emergence of EPS does not necessarily have Parkinson's.

While cannabis is the main ingredient THC（THC）, you can make the neurons to secrete more Dopamine so that the brain transfer of substances the ratio of re-to give balance and order to the EPS symptoms reduced.