One of the biggest tragedies of Alzheimer’s is by the time patients suspect something is wrong, there’s usually not a whole lot that medicine can do to help.
The disease causes buildups of amyloid plaques and tau protein tangles that irreversibly degrade the brain, which leads to symptoms like confusion and forgetfulness. At the moment, there are only handful of medications available to treat the disease. Most are targeted at maintaining memory, and there’s nothing to stop symptoms from getting progressively worse to the point where they become fatal. There also isn’t a lot of new development in the field. Pharma giants like Pfizer, for example, have discontinued their research in further treatments in part because so many clinical trials fail.
However, in a recent pilot study, researchers at Ohio State University found a potential alternative: deep brain stimulation.
Deep brain stimulation works by continuously tickling neurons in the frontal lobe of the brain with electrodes. Over the course of two years, three patients who had these electrodes implanted maintained more of their mental faculties than a group of control patients, who started out at similar stages of the disease. One woman in the test group even started making meals for herself—an ability she had lost in 2013.
Deep brain stimulation has been used to treat hundreds of thousands of patients with Parkinson’s, another kind of neurodegenerative disease. Researchers have also tried using it to treat Alzheimer’s, but only to mixed success. Most of these studies have targeted brain regions associated with memory and spatial awareness—usually some of the first to be destroyed by amyloid and tau.
In the Ohio State study, the researchers chose a different target: the frontal lobe, which is an outer region of the brain, and tends to suffer the effects of Alzheimer’s much later in the disease’s progression. This is the region that we use to make plans, cook, run errands—essentially, the skills needed to live alone.
“We chose this target that focuses on these cells that are still functioning pretty well, not actively degenerating like the memory circuits,” says Douglas Scharre, a neurologist and lead author of the paper. For reasons scientists don’t totally understand, “use it or lose it” is true when it comes to cognitive function. Stimulating these neurons with electrodes apparently keeps them active enough to slow down destructive chemical buildup around them.
The work, which was published (paywall) Jan. 30 in the Journal of Alzheimer’s Disease, isn’t promising to reverse Alzheimer’s-related brain damage, or stop it’s progression entirely. All three patients still worsened over the course of the study. But the level of independence they maintained—assessed through a Clinical Dementia Rating scale—was higher than those who did not receive this kind of stimulation. Notably, all of them chose to keep the stimulation going after the trial period ended because they liked its effects.