Here is an abridged audio-visual version of this article:
Introduction
We know that dopamine has different roles in different areas of the brain, such as for motor control, motivation, and reward, but dopamine also controls so-called “Go” and “No Go” processes, governing “action” or “inaction”.
Basically, dopamine motivates us towards movement, action or behaviors that are rewarding. Yet it is responsible for demotivating us, inhibiting or suppressing movements, actions or behaviors that are potentially harmful or unrewarding. When the “Go” (action) function of dopamine is active, the “No Go” function is suppressed, and vice verse, so these are competitive processes.
In this article, we look at how imbalances, over-activity, or under-activity in the “Go” and “No Go” processes provide useful explanatory insights into Parkinson’s diagnoses. While the main article isn’t solution orientated, the purpose is to provide a simple, but powerful, concept through which folks with many different types of chronic condition can understand themselves, and understand what is happening to them.
Indeed, I find with chronic conditions, just having this self-understanding, so that it is no longer just an unexplained mystery, can bring very significant relief.
“Go and No Go” or “Action and Inaction”
Both of rhese processes employ dopamine signaling to effect movement, motivation, and decision-making.
The “Go” function pushes us towards action or movement or behaviors associated with dopamine rewards. It drives us towards outcomes predicted to be helpful for survival.
The higher the dopamine levels, e.g. when an outcome is anticipated to be more highly rewarding, the stronger the Go function and the more likely it will drive us to action.
Conversely, the “No Go” function inhibits or suppresses actions, movements or behaviors which are likely to be unrewarding, have negative outcomes or be disappointing. It pushes us towards inhibition, restraint, and impulse control.
As dopamine levels go down, e.g. when an outcome is predicted to be more disappointing or punishing, then the No Go function becomes stronger. So the more likely it will restrain and prevent our actions or behaviors.
So the Go and No Go functions work in competition to regulate behavior. [Technically the two processes are governed by dopamine interacting with two different types of dopamine cell receptors, D1 type receptors for Go, and D2 for No Go].
A useful analogy is a car with a gas/accelerator pedal and a brake pedal. The gas pedal is like the Go function, the brake is like No Go. As dopamine goes up, the harder the gas pedal is pressed while slacking off the brake, and as dopamine goes down, the harder the break is pushed, and the foot is eased off the gas pedal.
Parkinson’s Disease
In folks with a Parkinson’s diagnosis, i.e. those of us who are stuck in stress-induced freeze response, the No Go function is being very strongly activated all the time, and the Go function is highly suppressed.