ScienceDaily: The study’s findings contradict the common notion that Alzheimer’s disease patients sleep during the day to make up for a bad night of sleep and point toward potential therapies to help these patients feel more awake.
The data came from study participants who were patients at UC San Francisco’s Memory and Aging Center and volunteered to have their sleep monitored with electroencephalogram (EEG) and donate their brains after they died.
Being able to compare sleep data with microscopic views of their post-mortem brain tissue was the key to answering a question that scientists have been pondering for years.
“We were able to prove what our previous research had been pointing to — that in Alzheimer’s patients who need to nap all the time, the disease has damaged the neurons that keep them awake,” said Grinberg, a neuropathologist who, along with psychiatrist Thomas Neylan, MD, is a senior author on the study, which appears in the April 4, 2022 issue of JAMA Neurology.
“It’s not that these patients are tired during the day because they didn’t sleep at night,” noted Grinberg. “It’s that the system in their brain that would keep them awake is gone.”
The opposite phenomenon occurs in patients with other neurodegenerative conditions, such as progressive supranuclear palsy (PSP), who were also included in the study. Those patients have damage to the neurons that make them feel tired, so they are unable to sleep and become sleep deprived.
Grinberg’s team developed the hypothesis that Alzheimer’s patients were having trouble staying awake, after discovering a set of neurons that keep us awake and that are affected in Alzheimer’s from the onset of the disease.