The impulse control center in the brain has been discovered. How could it help Parkinson’s patients?
Some of the most common treatments for Parkinson’s disease have side effects that affect decision-making. A study has now identified a part of the brain where these side effects could be triggered, potentially giving us a way to manage them.
Led by researchers at Fujita Health University in Japan, the study looked at the effects of pramipexole on mice. Pramipexole can be used alone or with other medicines to manage the symptoms of Parkinson’s disease, but it can also cause harmful compulsive behaviors such as gambling, overeating or shopping.
Pramipexole works by mimicking the neurotransmitter dopamine, which is reduced in the brains of people with Parkinson’s disease. In this case, the researchers engineered mice to show similar neuronal damage before treating them with pramipexole.
The mice were then subjected to risk-reward tasks designed to replace gambling, and indeed the mice exhibited compulsive behavior—choosing high-risk, high-reward options that corresponded to how addicted gamblers might act, write .
Most common treatments for Parkinson’s disease have side effects
Close observation of the mice’s brains led the researchers to a part of the nervous system called the external globus pallidus, which helps regulate voluntary and subconscious movements, and which was abnormally active in the gaming mice.
The external globus pallidus has already been successfully targeted by deep brain stimulation, and this research suggests that it could also help manage the side effects of pramipexole.
“Our findings could lead to the development of new drugs or interventions that specifically target the external globus pallidus,” says Hisayoshi Kubota, a neurologist at Fujita Health University.
“This would help prevent or reduce decision-making impairments in Parkinson’s patients.”
The discoveries could lead to the development of new drugs
When mice were injected with drugs to “turn off” the external globus pallidus, the animals’ gambling behavior became more normal, providing further evidence that neurons in the region and their connections are not working as they should.
This research is still in its infancy, but knowing where in the brain the wiring breaks down—assuming it’s the same in humans as it is in mice—is a good start. The researchers suggest that this could even help those who have compulsive habits, after further studies are conducted.
Although a means to reverse the neurodegeneration of the disease has not yet been discovered, improving therapies that slow its progression can make a significant difference. These new findings should help make these treatments more effective.
The research was published in
