Walter G. Besio, a professor of Biomedical Engineering at the University of Rhode Island, has developed a new kind of electrode that will allow for more accurate brain study.
Besio has been working for the last 20 years to develop the Tripolar Concentric Ring Electrode (TCRE), which improves signal quality when conducting studies that measure electrical activity from the brain. The brain signals received from these electrodes are much clearer and cleaner than any previous methods that have been used.
These electrodes not only record brain activity, but they can also deliver very small amounts of current called transcranial focal stimulation(TFS), that has been shown to be safe and beneficial in animal studies. Besio has been working with Lynn McCane, a graduate student in the University’s Interdisciplinary Neuroscience Program (INP) to test stimulation with these electrodes in people for the first time. The two are testing to see if TFS has any effects on healthy people, and hope to evaluate in future studies if TFS could treat neurological disorders such as depression, schizophrenia and epilepsy. In prior studies conducted by Besio, the TFS was shown to help reduce seizures in rats with epilepsy.
The team uses a computer software known as BCI 2000, which assists them in stimulus presentation and data collection. Subjects sit in a chair across the table from the experimenter and the characters A through J are presented on a screen in front of them. The subjects job is to remember the letter that is two-back and press a button when the letter appears again.
“It’s just a simple short-term working memory task,” said McCane. “Subjects do that for five minutes, then we wait 20 minutes and do it again, and then we wait another 20 minutes and do it again.”
Transcranial direct current stimulation (tDCS) has been shown to improve memory in this kind of task by delivering a low-level of current through the brain over a broad area of the cortex. Unlike tDCS, TFS stimulates a very small area, which provides more targeted stimulation.
“This is called transcranial stimulation, and it is very unique,” said McCane. “Recordings with these electrodes were able to see frequencies from the surfaces of the scalp in epileptic patients that were not seen in traditional electrodes.”
McCane’s job is to recruit subjects, perform the recording sessions and analyze the data for the safety test. The electrodes are placed on the head and the arms of the subject to ensure that no skin reaction occurs before starting the test.
“First, we test the TFS on the arm, and then on the head to check the skin,” said McCane. “Then we do the working memory task.”
The research being conducted is also a double-blind study, where some volunteers receive the stimulation before beginning the test, and some don’t, but neither the subject nor the experimenter know the condition. This is done to ensure fairness and credibility.
In the future, Dr. Besio and McCane hope broaden the use of transcranial focal stimulation to improve the overall quality of life of people with neurological disorders. By studying the brain and working memory with this new electrode, better treatments and therapies could be discovered.
“Once the study is finished, we can move on and decide how it can be used,” said McCane. “It has been shown to help epilepsy in the animal model and it really is a unique kind of simulation. Overall, the goal is to help people and make their lives better.”