Toronto: Has someone close to you just been diagnosed with Parkinson's disease? Well, chances are the disease has been progressing quietly but insidiously for more than 10 years, new research shows.

The research, published in the journal Nature Communications, sheds new light on the surprising resilience of the brain during the asymptomatic period of Parkinson's.

In their study, a team led by Universite de Montreal neuroscientist Louis-Eric Trudeau demonstrated that movement circuits in the brains of mice are insensitive to an almost total loss of active secretion of this chemical messenger.

This observation is surprising because dopamine is a chemical messenger recognised for its importance in movement. And in Parkinson's disease, dopamine levels in the brain drop inexorably.

"This observation went against our initial hypothesis, but that's often the way it is in science, and it forced us to re-evaluate our certainties about what dopamine really does in the brain," said Trudeau, a professor at the varsity's Department of Pharmacology and Physiology and Department of Neurosciences.

Using genetic manipulations, the team eliminated the ability of dopamine-producing neurons to release this chemical messenger in response to the normal electrical activity of these cells. Has someone close to you just been diagnosed with Parkinson's disease? Well, chances are the disease has been progressing quietly but insidiously for more than 10 years, new research shows.

The research, published in the journal Nature Communications, sheds new light on the surprising resilience of the brain during the asymptomatic period of Parkinson's.

In their study, a team led by Universite de Montreal neuroscientist Louis-Eric Trudeau demonstrated that movement circuits in the brains of mice are insensitive to an almost total loss of active secretion of this chemical messenger.

This observation is surprising because dopamine is a chemical messenger recognised for its importance in movement. And in Parkinson's disease, dopamine levels in the brain drop inexorably.

"This observation went against our initial hypothesis, but that's often the way it is in science, and it forced us to re-evaluate our certainties about what dopamine really does in the brain," said Trudeau, a professor at the varsity's Department of Pharmacology and Physiology and Department of Neurosciences.

Using genetic manipulations, the team eliminated the ability of dopamine-producing neurons to release this chemical messenger in response to the normal electrical activity of these cells.