Michel M. Maharbiz (Advisor)

One of the fundamental challenges in monitoring and modulating central nervous system activity is the lack of tools for simultaneous non-invasive interrogation of local neuronal ensembles in different regions of the brain. Despite recent advances in neural modulation techniques, including a rapidly expanding optogenetic and imaging toolset, we still lack a robust, minimally- invasive optogenetic stimulation platform. The ability to independently deliver light to multiple highly-localized regions of the brain would drastically improve in vivo optogenetic experiments. Illuminating a...

There is a need for non-invasive methods of neural probing without genetic modification for both clinical and scientific use. It has been found that action potentials are accompanied by small nanometer-scale membrane deformations in firing neurons. These mechanical waves, known as “action waves”, travel down axons in concert with action potentials and could be used to determine neuronal activity. Because acoustic waves are far less lossy in the brain than electromagnetic waves, we believe it may be possible to detect action waves from neurons up to 4 millimeters away with a...

Assembly at the microscale involves manipulation of one or more components relative to another in order to create a microstructure or device composed of these two or more components that would be difficult or impossible to monolithically fabricate. One specific class of problems that is well suited to microassembly rather than microfabrication is the creation of very high aspect ratio out-of-plane microstructures. As size and complexity of these out-of-plane microstructures grows, it becomes compelling if not necessary to automate the device assembly. To this end, we are developing...

Chronic monitoring of nerve activity with minimally invasive medical devices creates broad opportunities from therapeutic treatments to human augmentation. These closed-looped neural recording and modulation systems require small, low power wearable devices to enable freely moving subjects while still allowing real- time processing of recorded data. An ultrasonic backscatter system called Neural Dust (ND) demonstrated ultrasound's increased power efficiency over electromagnetic (EM) energy for sub-mm scale implantable devices used for wireless electrophysiological neural recording....