NU 2017-144

INVENTOR

Hooman Mohseni*

SHORT DESCRIPTION

A wireless system that uses infrared light to read and stimulate neurons

BACKGROUND

Building the capability to record the activity of hundreds of thousands of neurons simultaneously could lead to breakthroughs in our understanding of motor control, sensory perception and cognition. To do so, however, requires the development of novel methods for recording the simultaneous activity patterns of large populations of neurons in vivo. Currently, the two leading technologies for neural sensing are wired microelectrode arrays and wireless optogenetics-based devices. Microelectrode arrays has significant limitations, requiring the manual insertion of each neural probe into a particular brain region and are limited in the duration of microneedle implantation as there are negative impacts on brain tissue over time. The optogenetics-based approaches have proved to be more successful due to their wireless nature, but the ability to read several hundred probes continues to be challenging due to the high optical laser power needed and the adverse effect of heat on brain tissue.

ABSTRACT

A Northwestern inventor has developed a new method to read and stimulate neural signals that is both highly scalable and efficient. This method is based on implanting wireless and self-powered microprobes that transmit neural signals to the brain tissue. Each implanted microprobe, which is smaller than 50 µm, encodes the neural signals on an infrared beam that is sent from, and reflects directly back to, a receiver. The use of near-infrared light means the microprobes can in principle work with diameters as small as 5μm, a value comparable to the smallest diameter neuron cell bodies. In vivo and in vitro mouse data have shown that tens of thousands of neurons can be read simultaneously, and with little time delay resulting in a dramatic increase in detail from large scale neural recordings. In addition, the microprobes require only small amounts of energy to transmit information ensuring minimal heat dissipation inside the brain tissue even at a high transmission rate. Furthermore, novel nondestructive methods such as magnetic steering, optical or acoustic tweezing can be used to control the positioning of the microprobes in the brain medium. This technology has the power to develop a human-machine interface at a scale that is many orders of magnitude above existing technology.

APPLICATIONS

• Pain Management
• Brain-Machine link for quadriplegics
• General Brain-Machine interface

ADVANTAGES

• Wireless
• Scalable
• Reduced adverse side effects

PUBLICATIONS

In preparation

IP STATUS

Provisional and PCT applications have been filed.

In vivo experiments show returned signal from implanted probe (sphere retroreflector, green) ~500 mm deep inside an awake mouse brain, with excellent agreement to in vitro results.