A few weeks ago, my local Parkinson’s UK group welcomed a speaker. Dr. Masud Husain, who described his work at Oxford University on Motivation related to Parkinson’s.
Not only was the talk fascinating, it also felt very relevant. The behaviour patterns he described were uncomfortably familiar (in broad outline, although the lines were bolder and blacker for the people Dr. Husain was talking about than they are for me).
There was a man who had a stroke, affecting – very specifcally – the dopamine-producing regions of his brain. He recovered. But he didn’t want to do anything. He didn’t want to not do anything, either. He wasn’t depressed. He was inert. Apathetic. Completely unmotivated. He lost his job. He lost his home. His friends took him in, then they took him to the doctor. “He’s boring,” they said, “he didn’t used to be. He doesn’t do anything at all unless you tell him to do it.” The doctor referred him to Dr. Husain. Dr. Husain gave him Parkinson’s medication, and the man regained some of his lost motivation.
We were shown a video of a couple. She had Parkinson’s. He had gripes. “She doesn’t do anything”, he said. “Except watch television.” She agreed, but she looked uncomfortable. She didn’t want not to do anything – not in the abstract – she wanted to be her former, busy self. But she wasn’t. She couldn’t. Her get up and go had got up and gone.
Dopamine, explained Dr. Husain, has been associated primarily with motor functions, especially in Parkinson’s patients – but that isn’t its only function. It is also associated with pleasure, rewards, and motivation. Basically, it isn’t just the carrier for the signal from brain to muscle to do something. It’s what gets you moving. What gets you out of bed in the morning. What makes you send the signal in the first place.
I was particuarly intrigued by a couple of graphs, which can be seen in Fig. 4 of a “Note” published in Cortex, Volume 69, August 2015, Pages 40–46. The note, by Trevor T.-J. Chong, Valerie Bonnelle, Sanjay Manohar, Kai-Riin Veromann, Kinan Muhammed, George K. Tofaris, Michele Hu and Masud Husain is entitled “Dopamine enhances willingness to exert effort for reward in Parkinson’s disease”.
I have linked the graphic below. The caption is taken from the note.
My take on this is to observe that, with or without medication, the person with Parkinson’s is likely to find it harder to do something they aren’t very interested in than a “normal” person. Without medication, with greater interest, they will eventually reach the same level of motivation as normal (but it’s got to be a really interesting thing!). With medication, they reach “normal” sooner – and then exceed it. So if that really interesting thing comes along, the medicated person with Parkinson’s is not going to let it get away!
Everybody has different interests, and it goes without saying that painting a landscape is not going to float every Parkie’s boat, but relatively few will get excited about doing housework…