With careful thought, brain sensors connect neurons with actions
Neurologists who work to unlock the secrets of brain activity encounter what one might call the Las Vegas effect: “What happens in the brain, stays in the brain.”
The skull and dura mater are efficient insulators, keeping high-frequency electrical activity from leaving the brain. And between the blood-brain barrier and the brain’s aggressive immune system, nothing enters the brain without a fight—essential for staving off disease, but tough for medical interventions.
This is the challenge for Biomedical Engineering Associate Professor Justin Williams. He and his students develop sensor technologies that capture stronger and more medically valuable signals from the brain, for use in therapies for stroke and epilepsy patients. This computer-directed therapy could be beneficial for millions of people who are living with epilepsy or the effects of chronic stroke. Williams says it is especially promising for patients who have reached a plateau in traditional therapies.
With sensors that are placed directly on the dura mater, the tough coating between the skull and brain tissue, Williams’ advance represents a “tradeoff of risk and reward.” His approach has led to improved measurement of key brain activity while staying outside the blood-brain barrier to avoid complications of infection. The sensors work by monitoring the part of the brain responsible for a particular action—in stroke patients, for example, arm or leg movement. “We coordinate the brain’s intent to move your arm with the actual movement, with the goal of facilitating faster recovery,” Williams says.
This is a high-technology twist on traditional stroke therapies, which work to retrain the brain to control specific movements. But with technology, there is a precise connection between cause and effect. “The way the brain rewires is it looks for coincidences,” Williams says. “That’s the fundamental basis of learning and brain plasticity: the idea that ‘neurons that fire together, wire together.’”
Supported by both the National Institutes of Health and the Coulter Foundation for Translational Research, Williams has clinical trials underway with colleagues at UW Health. The epilepsy team includes Neurological Surgery Assistant Professors David Niemann and Karl Sillay. The stroke project includes Radiology Assistant Professor Vivek Prabhakaran and Neurology Assistant Professor Justin Sattin.