January 2018 issue
January 31, 2018 | In the wake of Functional Neuromodulation’s failed trial of DBS of the fornix for treatment of Alzheimer’s disease, two research teams and one neurotech startup are investigating different brain targets and therapeutic approaches to treating the disorder.
Dan Rizzuto’s team at Penn has reported positive results using cortical stimulation of the lateral temporal lobe to improve memory in Alzheimer’s patients. Rizzuto has spun off a commercial firm, Nia Therapeutics, which he introduced at the Neurotech Leaders Forum in San Francisco last fall. At the North American Neuromodulation Society meeting in Las Vegas earlier this month, Rizzuto described his team’s strategy of only delivering stimulation during periods of bad memory performance. Delivering stimulation during good memory period actually interferes with recall.
The Penn team has identified an ECoG biomarker based on the presence of both high frequency and low frequency oscillation to characterize good versus bad memory states and uses that indicator to drive stimulation. The team’s previous trial involved 36 human subjects and showed an 18 percent improvement in memory, equivalent to about three years of Alzheimer’s progression. The next study will test 26 subjects.
Meanwhile, a research team at Ohio State’s Wexner Medical Center has reported positive results from stimulation of the frontal lobes in three patients with Alzheimer’s disease. Reporting in the Journal of Alzheimer’s Disease, Douglas Scharre and colleagues from the Neurological Institute at Wexner found that DBS targeting frontal brain regions can reduce the overall performance decline typically seen in people with mild or early stage Alzheimer’s.
“We have many memory aides, tools, and pharmaceutical treatments to help Alzheimer’s patients with memory, but we don’t have anything to help with improving their judgments, making good decisions, or increasing their ability to selectively focus attention on the task at hand and avoid distractions. These skills are necessary in performing daily tasks such as making the bed, choosing what to eat and having meaningful socializing with friends and family,” said Scharre. “The frontal lobes are responsible for our abilities to solve problems, organize and plan, and utilize good judgments. By stimulating this region of the brain, the Alzheimer’s subjects cognitive and daily functional abilities as a whole declined more slowly than Alzheimer’s patients in a matched comparison group not being treated with DBS,” he said.
Scharre collaborated with Ali Rezai, now at West Virginia University. “Our findings suggest that frontal network modulation to improve executive and behavioral deficits should be further studied in patients with Alzheimer’s disease,” said Rezai.
All three study participants showed improvement. One subject was not doing any meal preparation when she entered the study in 2013, but after two years of DBS, she could independently initiate preparations of a simple meal, assemble ingredients, and cook the meal.
Next, Ohio State researchers want to explore non-surgical methods to stimulate the frontal lobe.
