Deep brain stimulation is a procedure in which a surgeon implants a neurostimulator, which emits electrical stimulation to certain areas of the brain. The Mayo Clinic notes that the U.S. Food and Drug Administration (FDA) approved the use of deep brain stimulation in 1997 for essential tremor and later in 2002 for Parkinson's disease. But can it work as a treatment for Alzheimer's disease?
In Parkinson's disease, deep brain stimulation can help with symptoms such as walking problems, rigidity, slowed movement and tremor. The MayoClinic.com points out that Parkinson's disease patients who undergo deep brain stimulation include those who do not have stable responses to their medication, such as levadopa. In these cases, deep brain stimulation works by sending electrical signals to areas of the brain involved with movement, which prevents abnormal neural signals.
The National Institute of Neurological Disorders and Stroke (NINDS) explains that the set up for deep brain stimulation involves three parts: an electrode; a neurostimulator, which is the battery pack; and the extension. The surgeon implants the electrode in a specific region of the brain, which he or she identifies using an imaging scan, such as a magnetic resonance imaging (MRI) scan or computed tomography (CT) scan. With the neurostimulator, the surgeon implants that near the collarbone, then connects the two parts with the extension, which is also underneath the skin. The electrical signals are sent from the neurostimulator through the extension and up through the electrode to the brain.
In the Alzheimer's disease study published in the Annals of Neurology, the researchers investigated the effects of deep brain stimulation on a group of patients with mild Alzheimer's disease. HealthDay News reports that the study consisted of six patients with electrodes implanted in areas of their brain associated with memory, which lasts for 12 months. During this period where they underwent deep brain stimulation, the participants continued to use their Alzheimer's disease medications. The researchers found that some patients had an improvement in cognition. Using imaging scans, the researchers saw that the participants had an increase in glucose metabolism, which shows a higher level of brain activity. The participants did not have sleep problems or changes in weight or body chemistry after undergoing the surgery for deep brain stimulation.
While the results from this study show some promise, the results are very preliminary. To investigate further, HealthDay News reports that the researchers will do a phase 2 study, which will include more participants.