This post is a game of two halves.
The first half will explain the concept of a surgical procedure for Parkinson’s called ‘subthalamic deep brain stimulation‘, in which doctors permenantly implant electrodes into the brain to stimulate a region – the subthalamic nucleus. By stimulating this region with electrical impulses, doctors can provide a better quality of life (in most cases) to people with severe features of Parkinson’s.
In the second half of this post, we will look at an approach to doing the same thing,… but without the electrodes.
Rather, researchers are using gene therapy.
In today’s post, we will discuss what deep brain stimulation is, what gene therapy is, and how the gene therapy approach is having a different kind of impact on the brain to that of deep brain stimulation.
Welcome to the first half of today’s post.
It begins with you asking the question:
What is deep brain stimulation?
Deep brain stimulation (or DBS) is a treatment method that involves embedding electrodes into the brain to help modulate the brain activity involved in movement.
It is a prodcedure that is usually offered to people with Parkinson’s who have excessive tremor or debilitating dyskinesias.
First introduced in 1987, deep brain stimulation consists of three components: the pulse generator, an extension wire, and the leads (which the electrodes are attached to). All of these components are implanted inside the body. The system is turned on, programmed and turned off remotely.
The contents of today’s post may not be appropriate for all readers. An illegal and potentially damaging drug is discussed. Please proceed with caution.
3,4-Methylenedioxymethamphetamine (or MDMA) is more commonly known as Ecstasy, ‘Molly’ or simply ‘E’. It is a controlled Class A, synthetic, psychoactive drug that was very popular with the New York and London club scene of the 1980-90s.
It is chemically similar to both stimulants and hallucinogens, producing a feeling of increased energy, pleasure, emotional warmth, but also distorted sensory perception.
Another curious effect of the drug: it has the ability to reduce dyskinesias – the involuntary movements associated with long-term Levodopa treatment.
In today’s post, we will (try not to get ourselves into trouble by) discussing the biology of MDMA, the research that has been done on it with regards to Parkinson’s disease, and what that may tell us about dyskinesias.
Good times. Source: Carwash
You may have heard this story before.
It is about a stuntman.
His name is Tim Lawrence, and in 1994 – at 34 years of age – he was diagnosed with Parkinson’s disease.
Tim Lawrence. Source: BBC
Following the diagnosis, Tim was placed on the standard treatment for Parkinson’s disease: Levodopa. But after just a few years of taking this treatment, he began to develop dyskinesias.
Dyskinesias are involuntary movements that can develop after regular long-term use of Levodopa. There are currently few clinically approved medications for treating this debilitating side effect of Levodopa treatment. I have previously discussed dyskinesias (Click here and here for more of an explanation about them).
As his dyskinesias progressively got worse, Tim was offered and turned down deep brain stimulation as a treatment option. But by 1997, Tim says that he spent most of his waking hours with “twitching, spasmodic, involuntary, sometimes violent movements of the body’s muscles, over which the brain has absolutely no control“.
And the dyskinesias continued to get worse…
…until one night while he was out at a night club, something amazing happened:
“Standing in the club with thumping music claiming the air, I was suddenly aware that I was totally still. I felt and looked completely normal. No big deal for you, perhaps, but, for me, it was a revelation” he said.
His dyskinesias had stopped.