Flexible nanoelectrodes can provide effective brain stimulation, Rice Univeristy Engineered materials are soft on neurons and can serve as sensory prostheses.
These types of implantable medical devices designed for brain stimulation are usually very hard and bulky for what is one of the softest and hardest tissues.
To solve that problem, Rice University engineers developed tiny, highly invasive nanoelectrodes that can serve as an implantable platform to deliver long-term, high-resolution stimulation therapy.
According to a study published in Cell Reports, these small devices that are implanted in the body are stable, durable, and the tissue-electrode interface has little scar or damage to the mouse. The devices produced electrical stimulation that more closely matched neural signal patterns and amplitudes than stimulation from intracortical electrodes.
The high compatibility of the device and the precise control of spatio-temporal stimuli may allow the development of new brain stimulation systems such as neural prostheses for patients with sensory or motor disorders.
“This paper uses imaging, behavioral and histological methods to show how electrodes implanted in the body can improve stimulation efficiency,” said Lan Luan, assistant professor of electrical engineering at the computer and the corresponding author of the said study. “Elected we deliver small amounts of electricity to stimulate nerve activity in a controlled manner.
“We can reduce the current to stimulate neuronal activity by orders of magnitude. Pulses can be as subtle as a few hundred microseconds in length and one or two microamperes in amplitude.
A new electrode design developed by researchers at the Rice Neuroengineering Initiative represents a significant improvement over conventional electrodes used to treat conditions such as Parkinson’s disease, epilepsy and other neurological disorders, which can cause negative physical responses and negative changes in neuronal activity.
Chong Xie, assistant professor of electrical and computer engineering and corresponding author of the study said, “Conventional electrodes are very invasive.” They take thousands or even millions of neurons at the same time.
“Each of these neurons should have its own rhythm and be organized in a certain pattern. But when you shock them at the same time, you disrupt their activity. In some cases, it works well for you and has the desired therapeutic effect. But if, for example, you want to encode emotional information, you need more control over the stimulus.
Xie compared stimulation from conventional electrodes to the disturbing effect of “blowing a horn in everyone’s ears or broadcasting a voice” in a room full of people.
He said: “We used to have this big speaker, but now everyone has headphones.
The possibility of adjusting the frequency, duration and strength of the signal may allow the creation of new sensor prostheses.
“Neuron upgrades are more widespread if you use a large current,” Luan said. “We can reduce the current and show that we have a lot of targeted input. This can lead to higher resolution stimulus devices.
Luan and Xie are directors of the Rice Neuroengineering Initiative and their lab is also working on the development of a visual prosthesis for blind patients.
“Imagine one day being able to implant an electrode system to restore impaired emotional function: the more attention is focused on the neuron, the better your emotions are,” Luan said.
Previous types of devices were used to record brain activity.
Luan said, “We have several papers showing that the close tissue coupling created by our flexible electrode design improves our ability to record brain activity over long periods of time with good signal-to-noise ratio. ,” said Luan. was promoted to partner. teacher from July 1.
Source: Rice University
