Intriguing brain device similar to heart pacemaker

Keeping up the appearance of having all your marbles is hard work, but [very] important.
― Sara Gruen, Water for Elephants

            Did you see the news coverage of the latest Alzheimer’s testing?  Test subjects are receiving a brain device similar to a heart pacemaker and initial results appear positive. 

Researchers at Ohio State University began in October 2012 to test deep-brain stimulation surgery to see if they can stave off the rapid decline of memory loss and other losses attributable to Alzheimer’s Disease.  The first patient, Kathy Sanford, experienced  enough success that her results are the ones that ignited the news media interest.

Ms. Sanford had been diagnosed with early-stage Alzheimer’s, and it was getting worse.  She still lived independently, posting sticky notes around her house as reminders to herself.  However, she could no longer perform her full-time job.

She underwent the five-hour operation necessary to implant the device, and scientists and doctors will track her for at least two years.  This is an ongoing evaluation about which Doctors feel cautiously optimistic.  The lengthy operation involves drilling holes into the patient’s skull so tiny wires can be implanted into just the right spots.

In December, Johns Hopkins University here in Maryland became part of the study.  The surgery is part of a federally funded, multicenter clinical trial marking a new direction in clinical research designed to slow or halt the ravages of the disease, which slowly robs its mostly elderly victims of a lifetime of memories and the ability to perform the simplest of daily tasks, researchers at Johns Hopkins say. Instead of focusing on drug treatments, many of which have failed in recent clinical trials, the research focuses on the use of the low-voltage electrical charges delivered directly to the brain.

As part of a preliminary safety study in 2010, the devices were implanted in six Alzheimer’s disease patients in Canada. Researchers found that patients with mild forms of the disorder showed sustained increases in glucose metabolism, an indicator of neuronal activity, over a 13-month period. Most Alzheimer’s disease patients show decreases in glucose metabolism over the same period.

This type of deep-brain stimulation isn’t entirely new.  Many people have had DBS to block Parkinson tremors and other movement disorders.  The mild jolts of electricity quiet overactive nerve cells, and move them toward calm.  There are few, if any side effects.    For Alzheimer’s patients, the hope is that constant electrical stimulation of brain circuits involved in memory and thinking might keep those neural networks active for longer, essentially bypassing some of the damage dementia does over time to the brain.

Some of the oral medications that were developed to slow the rapid progress of memory loss and other Alzheimer’s symptoms, have turned out to be a disappointment for those who work with the disease, including neurologists and research scientists.  High hopes during early medication trials could not be backed up by actual results.

“Recent failures in Alzheimer’s disease trials using drugs such as those designed to reduce the buildup of beta amyloid plaques in the brain have sharpened the need for alternative strategies,” says Paul B. Rosenberg, M.D., an associate professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine, and site director of the trial’s Johns Hopkins location. “This is a very different approach, whereby we are trying to enhance the function of the brain mechanically. It’s a whole new avenue for potential treatment for a disease becoming all the more common with the aging of the population.”

Like the medication, the pace maker approach will not target the cause of the disease, nor cure it.  It is hoped that it will slow the damage of the disease.  The pace maker study will be small, as this research is so very new.  Only a few dozen people with early-stage Alzheimer’s will be implanted with the new device in a small number of hospitals. Only patients whose cognitive impairment is mild enough that they can decide on their own to participate will be included in the trial.

According to a recent Johns Hopkins press release, the surgery involves drilling holes into the skull to implant wires into the fornix on either side of the brain. The fornix is a brain pathway instrumental in bringing information to the hippocampus, the portion of the brain where learning begins and memories are made, and where the earliest symptoms of Alzheimer’s appear to arise. The wires are attached to a pacemaker-like device, the “stimulator,” which generates tiny electrical impulses into the brain 130 times a second. Doctors say that patients don’t feel the current.

For the trial, all of the patients will be implanted with the devices. Half will have their stimulators turned on two weeks after surgery, while the other half will have their stimulators turned on after one year. Neither the patients nor the doctors treating them will know which group gets an early or later start.

As for Ms. Sanford, she and her family are very encouraged.  They have already seen improvement in various problem-solving exercises, and are optimistic that her deficits are at least holding steady.

Thanks for reading. Stay well. See you next week.