According to Borghammer’s “Aha” moment, it came almost 20 years ago. Neuroscientists were reading papers from researchers investigating REM sleep behavior disorders (RBD). This is a condition in which people develop dreams, often discovered in people who develop Parkinson’s disease, and may be a form of early neurological symptoms.

However, rather than starting from the brain, the team looked for the loss of nerve cells in the heart instead. Parkinson’s disease has historically been linked to depletion of neurons in the brain, but it also affects cardiac neurons that manage autonomic nervous functions such as heart rate and blood pressure. And say Borgamer“In all these patients, the heart is invisible. It’s gone.”

Of course, it’s not literal. However, in these people, neurons that produce the neurotransmitter norepinephrine, which helps control heart rate, were depleted to the point that the heart did not appear on scans using radioactive tracers. This type of neuronal loss is linked to Parkinson’s disease, but no one was diagnosed with the disease at the time, and brain scans appeared to be normal.

What struck Borghammer was that Parkinson’s disease appears to have not followed the same trajectory in all affected people. Although RBD strongly predicts Parkinsonson’s predictions No one has Parkinson’s experience. RBD.

“I realized that Parkinson’s disease must be at least two types,” says Borgamer. Neuronal loss is primarily confined to the brain From the beginning. By 2019, Borghammer,…