It has the makings of a science fiction movie: Zap someone’s brain with mild jolts of electricity to try to stave off the creeping memory loss of Alzheimer’s disease.
A dramatic shift is beginning in the disappointing struggle to find something to slow the damage of this epidemic: The first U.S. experiments with “brain pacemakers” for Alzheimer’s are getting under way. Scientists are looking beyond drugs to implants in the hunt for much-needed new treatments.
The research is in its infancy. Only a few dozen people with early stage Alzheimer’s will be implanted in a handful of hospitals.
Ohio resident Kathy Sanford, 57, was among the first to sign up. Her early stage Alzheimer’s was gradually getting worse.
Then doctors at Ohio State University explained that constant electrical stimulation of brain circuits involved in memory and thinking might keep those neural networks active for longer, essentially bypassing some of dementia’s damage.
Sanford decided it was worth a shot. “The reason I’m doing it is, it’s really hard to not be able, sometimes, to remember,” Sanford said.
A few months after the five-hour operation, Sanford said she felt good, with an occasional tingling that she attributes to the electrodes. A battery-powered generator near her collarbone powers them, sending the tiny shocks up her neck and into her brain. It’s too soon to know how she’ll fare; scientists will track her for two years.
More than 5 million Americans have Alzheimer’s, and that number is expected to rise rapidly as baby boomers age. Today’s drugs only temporarily help some symptoms. Attempts to attack Alzheimer’s presumed cause, a brain-clogging gunk, so far haven’t panned out.
The new approach is called deep brain stimulation, or DBS. While it won’t attack Alzheimer’s root cause either, “maybe we can make the brain work better,” said Ohio State neurologist Dr. Douglas Scharre.
Implanting electrodes into the brain isn’t new. Between 85,000 and 100,000 people around the world have had DBS to block the tremors of Parkinson’s disease and other movement disorders. Canadian researchers back in 2003 stumbled onto the Alzheimer’s possibility. They switched on the electrical jolts in the brain of an obese man and unlocked a flood of old memories. Continuing his DBS also improved his ability to learn. He didn’t have dementia, but researchers wondered if they could spur memory-making networks in someone who did.
A healthy brain is a connected brain. One circuit signals another to switch on and retrieve the memories needed to, say, drive a car or cook a meal.
At least early in the disease, Alzheimer’s kills only certain spots. But the disease’s hallmark gunky plaques act as a roadblock, stopping the “on” switch so that healthy circuits farther away are deactivated, said Dr. Andres Lozano, a neurosurgeon at Toronto Western Hospital whose research sparked the interest.
So the plan was to put the electrodes into hubs where brain pathways for memory, behavior, concentration and other cognitive functions converge, to see if the jolts reactivate those silenced circuits, added Ohio State neurosurgeon Dr. Ali Rezai.
Lozano’s team found the first clue that it’s possible by implanting six Alzheimer’s patients in Canada. After at least 12 months of continuous stimulation, brain scans showed a sign of more activity in areas targeted by Alzheimer’s. Suddenly, the neurons there began using more glucose, the fuel for brain cells. “It looked like a blackout before. We were able to turn the lights back on in those areas,” Lozano said.
Lauran Neergaard covers medical issues for the Associated Press.