Project Goals: The PI will investigate using light from flexible displays to wrap around and stimulate nerves genetically modified to be light sensitive.
a) Nontechnical Abstract:
Biolelectronic medicine is a new approach to treating diseases by direct stimulation of specific nerves which triggers the body to treat itself without the use of pharmaceuticals. This emerging area of research shows incredible promise for a variety of diseases, but current methods of stimulating individual nerves within a fiber are inaccurate and/or cause damage to the nerve. Optogenetics is a new technique has revolutionized interface with the nervous system by using light to stimulate nerves rather than more traditional electrodes. Light can stimulate a nerve without physically penetrating and damaging the nerve like many electrical stimulation techniques. However the optical stimulation has only been shown with low resolution in two dimensional patterns. This work exploit flexible display technology used in flat panel televisions; a small array will wrap around and stimulate the nerve in a three dimensional configuration. The goal is to simultaneously shine several pixels, each too weak to stimulate, on the nerve to get enough light to activate the nerve where the beams cross. This will give very specific targeting of nerves. In addition, this grant will support the development of a bioelectronics workshop. The workshop will allow students, especially underrepresented minority students, to make their own measurements from the brain of a bug and their own muscles. The students will learn about how these bioelectronics can enable therapeutic and prosthetic technology.
b) Technical Abstract:
Bioelectronic medicine is a new approach to treating disease by direct stimulation of specific nerves which triggers the body to treat itself without the use of pharmaceuticals. Targeted stimulation of the nervous system can upregulate the body's response to immune deficiency and downregulate its response to autoimmune disease. Traditional nerve stimulation uses electrical stimulation outside of the nerve fiber to target individual axons or groups of axons, but the resolution of this technique is very poor. Squeezing the nerve can improve this resolution but only near the surface. More invasive techniques cut open the nerve and substructures to place extremely fine wires next to the nerves to improve resolution, but this is very invasive and can cause damage. This work leverages a new technique for neural stimulation, optogenetics. Optogenetics is the use of light to stimulate neurons that have been genetically sensitized to specific wavelengths. While this technique has revolutionized neural interface, the implementation has been fairly low resolution and two dimensional. This work uses ultra-thin flat panel display technology wrapped around the sciatic nerve to stimulate motor neurons. This enables a stimulation technique that is non-invasive to the nerve. In addition, it will increase the resolution of stimulation beyond other techniques external to the nerve. Multiple emitters can be used with optical power below the threshold for optogenetic stimulation simultaneously, so the intersection of the emitted light from each of the pixels will be sufficient to stimulate the axon. This should increase the resolution with which stimulation can be targeted within a nerve fiber. The efficacy of the system will be demonstrated using transgenic mice with motor neurons specifically transfected. An arrays of emitters will be wrapped around a mouse sciatic nerve with electromyography (EMG) used to confirm the stimulation. In addition, this grant will support the development of a bioelectronics workshop. The workshop will allow students, especially underrepresented minority students, to make their own neural and EMG recordings. The students will learn about how these bioelectronics interfaces can enable therapeutic and prosthetic technology.
