Rice University engineers develop ultra-flexible nanoelectrodes for brain stimulation therapy

The Future of Sensory Prosthetic Devices with Ultra-flexible Electrodes

The nanoelectrodes provide precise and minute electrical pulses, enabling controlled neural activity excitation. In addition, compared to traditional electrodes, they need a significantly reduced current for neuronal activation, achieving an order of magnitude improvement.

The comparison is evident when one looks at the current state of brain stimulation therapies. Traditional implantable electrodes, used for treating conditions such as Parkinson's disease, epilepsy, and obsessive-compulsive disorder, often cause adverse tissue reactions and unintended alterations in neural activity.

Chong Xie, a corresponding author of the study and an associate professor of electrical and computer engineering, likened the effect of traditional electrodes to "blowing an airhorn in everyone's ear or having a loudspeaker blaring" in a room full of people. In contrast, the nanoelectrodes developed at Rice offer more precision and less disruption.

"Instead of a loudspeaker, now everyone has an earpiece," Xie said.

The advanced control over signal frequency, duration, and intensity could open the door to innovative sensory prosthetic devices. "When a larger current is employed, neuron activation becomes more widespread and diffuse," said Luan. "However, we successfully reduced the current and demonstrated a significantly more focused activation."

Luan and Xie are part of the Rice Neuroengineering Initiative, a collaborative effort to create an implantable visual prosthetic device for visually impaired patients. They envisage a future where these electrode arrays can be implanted to restore poor sensory function, with the level of precision in neuron activation crucial for generating accurate and precise sensations.

Starting from July 1, Luan will assume the position of associate professor. Under his leadership, the team has published a series of research papers demonstrating the electrode's capability to facilitate improved recording of brain activity over extended periods.

Roy Lycke, a postdoctoral associate in electrical and computer engineering, and Robin Kim, a graduate student, have led the study. Lycke and Kim have played vital roles in conducting the research, supported by the National Institute of Neurological Disorders and Stroke and Rice internal funds.