June 4, 2012
Researchers Experimenting With Electronic Brain Stimulation Techniques
Despite the fact that it has been vilified by some in the past, scientists are experimenting with various types of electrical brain stimulation, hoping that some day it will not only be able to treat a wide array of disorders but also enhance a person's cognitive abilities.
In a June 2 article, Kerri Smith of the Observer focuses on several different varieties of such treatments, including transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and deep brain stimulation (DBS), which are currently being studied by experts hoping to firmly establish their benefits to the medical community.The first technique, TMS, is used by some experts to analyze the areas of the brain that control movement, she said. Furthermore, the stimulation technique "may yet prove to be an effective therapy for all kinds of disorders of brain and mind."
"In the United States, TMS is already in use for severe depression, and although it hasn't made its clinical debut here yet, some researchers think it might one day be able to treat not only depression but obsessive-compulsive disorder, tinnitus, even Alzheimer's disease."
Smith adds that the technique could also be used to enhance the function of a healthy brain.
The second method, tDCS, is being used by researchers at University College London (UCL) in order to try and treat speech problems that result from strokes.
"Techniques such as this were in vogue in Europe as early as the late 1880s, where doctors would pass a current through the brain or a muscle to discern disability," Smith said. "The modern kit is simple; a battery powering a pair of electrodes stuck on to the scalp over the parts of the brain involved in a particular task."
Jenny Crinion, a speech therapist at the UCL Institute of Cognitive Neuroscience, and colleagues are working with 24 patients trying to help overcome conditions like aphasia, a condition in which patients are left struggling to find the words they want to say.
With such patients, Smith says that the researchers apply electrodes to the left prefrontal cortex -- the area of the head known to be affected by strokes -- and deliver a mild current for a 20 minute period while patients are focused on a laptop displaying pictures which they are asked to identify.
The training continues for a period of six weeks, and Crinion tells the Observer that the program has been effective. Without brain stimulation, the computer-based training improves patient re-learning by 55%, while the stimulation increases that figure to 92%.
The third type featured in the article, DBS, requires surgeons to "implant electrodes directly into the bit of the brain they want to stimulate," Smith wrote. "It's used when a region of the brain doesn't function properly or is missing. It's been pioneered in Parkinson's disease, where a small group of neurons buried deep inside the brain starts to die and the electrodes take over their job."
The procedure is currently in clinical use in the UK, and globally, tens of thousands of patients have undergone the procedure, she said.
"There are hints that it could also help psychiatric conditions," Smith explained. "The next likely candidate is depression, while some researchers have even implanted electrodes to manage the symptoms of obsessive-compulsive disorder. But, researchers caution, DBS is a serious operation and not an option for all Parkinson's patients. Drugs are still the best way for most to relieve their condition."