What do extreme sports, doomscrolling, addiction, Parkinson's disease, and ADHD all have in common? When Glenn Peterson started on a higher dosage of medication to treat his Parkinson's disease symptoms, he didn't expect the consequences it would have. He was taking a dopamine precursor medication — a drug the body converts to dopamine when it reaches the brain — to treat his symptoms. While the brain converts dopamine precursors directly into dopamine, dopamine-agonist medications mimic dopamine by activating dopamine receptors in the brain. "I kind of started to realise that what was driving me to spend was also driving me to scroll."