Noninvasive brain implant could someday translate thoughts into movement

ScienceDaily (June 17, 2011) — A brain implant developed at the University of Michigan uses the body's skin like a conductor to wirelessly transmit the brain's neural signals to control a computer, and may eventually be used to reactivate paralyzed limbs.

The implant is called the BioBolt, and unlike other neural interface technologies that establish a connection from the brain to an external device such as a computer, it's minimally invasive and low power, said principal investigator Euisik Yoon, a professor in the U-M College of Engineering, Department of Electrical Engineering and Computer Science.

Currently, the skull must remain open while neural implants are in the head, which makes using them in a patient's daily life unrealistic, said Kensall Wise, the William Gould Dow Distinguished University professor emeritus in engineering.

BioBolt does not penetrate the cortex and is completely covered by the skin to greatly reduce risk of infection. Researchers believe it's a critical step toward the Holy Grail of brain-computer interfacing: allowing a paralyzed person to "think" a movement.

"The ultimate goal is to be able to reactivate paralyzed limbs," by picking the neural signals from the brain cortex and transmitting those signals directly to muscles, said Wise, who is also founding director of the NSF Engineering Research Center for Wireless Integrated MicroSystems (WIMS ERC). That technology is years away, the researchers say.

Another promising application for the BioBolt is controlling epilepsy, and diagnosing certain diseases like Parkinson's.

The concept of BioBolt is filed for patent and was presented on June 16 at the 2011 Symposium on VLSI Circuits in Kyoto, Japan. Sun-Il Chang, a PhD student in Yoon's research group, is lead author on the presentation.

The BioBolt looks like a bolt and is about the circumference of a dime, with a thumbnail-sized film of microcircuits attached to the bottom. The BioBolt is implanted in the skull beneath the skin and the film of microcircuits sits on the brain. The microcircuits act as microphones to 'listen' to the overall pattern of firing neurons and associate them with a specific command from the brain. Those signals are amplified and filtered, then converted to digital signals and transmitted through the skin to a computer, Yoon said.

Another hurdle to brain interfaces is the high power requirement for transmitting data wirelessly from the brain to an outside source. BioBolt keeps the power consumption low by using the skin as a conductor or a signal pathway, which is analogous to downloading a video into your computer simply by touching the video.

Eventually, the hope is that the signals can be transmitted through the skin to something on the body, such as a watch or a pair of earrings, to collect the signals, said Yoon, eliminating the need for an off-site computer to process the signals.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Michigan, via EurekAlert!, a service of AAAS.

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

Noninvasive brain implant could someday translate thoughts into movement

ScienceDaily (June 17, 2011) — A brain implant developed at the University of Michigan uses the body's skin like a conductor to wirelessly transmit the brain's neural signals to control a computer, and may eventually be used to reactivate paralyzed limbs.

The implant is called the BioBolt, and unlike other neural interface technologies that establish a connection from the brain to an external device such as a computer, it's minimally invasive and low power, said principal investigator Euisik Yoon, a professor in the U-M College of Engineering, Department of Electrical Engineering and Computer Science.

Currently, the skull must remain open while neural implants are in the head, which makes using them in a patient's daily life unrealistic, said Kensall Wise, the William Gould Dow Distinguished University professor emeritus in engineering.

BioBolt does not penetrate the cortex and is completely covered by the skin to greatly reduce risk of infection. Researchers believe it's a critical step toward the Holy Grail of brain-computer interfacing: allowing a paralyzed person to "think" a movement.

"The ultimate goal is to be able to reactivate paralyzed limbs," by picking the neural signals from the brain cortex and transmitting those signals directly to muscles, said Wise, who is also founding director of the NSF Engineering Research Center for Wireless Integrated MicroSystems (WIMS ERC). That technology is years away, the researchers say.

Another promising application for the BioBolt is controlling epilepsy, and diagnosing certain diseases like Parkinson's.

The concept of BioBolt is filed for patent and was presented on June 16 at the 2011 Symposium on VLSI Circuits in Kyoto, Japan. Sun-Il Chang, a PhD student in Yoon's research group, is lead author on the presentation.

The BioBolt looks like a bolt and is about the circumference of a dime, with a thumbnail-sized film of microcircuits attached to the bottom. The BioBolt is implanted in the skull beneath the skin and the film of microcircuits sits on the brain. The microcircuits act as microphones to 'listen' to the overall pattern of firing neurons and associate them with a specific command from the brain. Those signals are amplified and filtered, then converted to digital signals and transmitted through the skin to a computer, Yoon said.

Another hurdle to brain interfaces is the high power requirement for transmitting data wirelessly from the brain to an outside source. BioBolt keeps the power consumption low by using the skin as a conductor or a signal pathway, which is analogous to downloading a video into your computer simply by touching the video.

Eventually, the hope is that the signals can be transmitted through the skin to something on the body, such as a watch or a pair of earrings, to collect the signals, said Yoon, eliminating the need for an off-site computer to process the signals.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Michigan, via EurekAlert!, a service of AAAS.

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

New technology could inspire brain implant for detecting and treating seizures

ScienceDaily (June 2, 2011) — Tiny electrodes have been coated with a drug-loaded polymer in an attempt to design an implant capable of detecting a number of neurological symptoms, such as those associated with an epileptic seizure, and treating them simultaneously.

In a study published June 2, 2011 in IOP Publishing's Journal of Neural Engineering, researchers have developed a novel technology to precisely modulate individual neurons in rats, allowing the molecular, neuronal, and circuit functions to be analysed with unprecedented precision.

Based on the electrical conducting properties of the polymer Polypyrrole (PPy), the researchers, from the University of Pittsburgh, have demonstrated a novel way of loading specific drugs onto an array of electrodes and triggering their release into cultured neurons, allowing for a more precise insight into the cellular mechanisms of neuronal networks.

On top of this, the researchers have also demonstrated how the release of drugs could be informed, in real-time, by the recording of activity in neurons, a step essential for creating a closed-loop system that both diagnoses and treats symptoms simultaneously, creating several potential applications.

Co-author Professor X Tracy Cui said, "We envision an implanted device in the future that will monitor the brain activity, detect or predict an onset of epileptic seizure, and send the command to the electrode at the most appropriate location, releasing an anti-convulsive drug to prevent the seizure."

Multielectrode arrays (MEAs) -- small devices that can control or record the electrical circuitry in neurons -- have long been used as a way of measuring neuronal activity and transforming this into an action; technologies such as ear implants and cardiac pacemakers have benefited from them.

Recent advances, however, have allowed MEAs to be coupled with devices that release specific drugs in order to test how neural circuits function, as well as investigating the underlying mechanisms within neuronal cells.

The researchers coated PPy, containing all of the necessary neurochemicals, onto an MEA. Whilst positioned on the cultured rat brain, the polymer was electrically stimulated, causing the neurochemicals to dissociate and diffuse away to the necessary locations.

Results showed that the drugs retained their activity and function with spatial and temporal precision.

Current state-of-the-art drug delivery methods, such as picospritzer and ionotopheriesis, give researchers a greater understanding of cellular mechanisms of neural dynamics; however, both of these techniques are limited to a few sites and face the risk of drug leakage.

By having the required neurochemicals dissociate from the polymer, this technique avoids the need for an external reservoir containing the drug, which would greatly increase the size of a potential implant and could cause tissue damage.

Professor Cui continues, "By directly loading a drug of interest onto an individual electrode site and using an electrical signal to trigger its release, we can precisely control the drug delivery site with ease. Additionally, our technology can be used for a combination of exogenous chemicals such as subtype-specific receptor antagonists, thus potentially allowing for more precise dissection of neural circuit function at the molecular level."

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Institute of Physics, via EurekAlert!, a service of AAAS.

Journal References:

Stauffer et al. Rapid modulation of local neural activity by controlled drug release from polymer-coated recording microelectrodes. J. Neural Eng., 2011 [link]Stauffer et al. Rapid modulation of local neural activity by controlled drug release from polymer-coated recording microelectrodes. Journal of Neural Engineering, 2011; [link]

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

View the original article here