Neurons encode information by electrical signals. To understand information processing and storage in neuronal networks, one of the most important tactics is to accurately record the small electrical signals generated by individual neurons over time. However, challenges associated with sensitive and noninvasive detection of small neuroelectric activities have hampered the effort for a better understanding of this complex process. Intracellular recording is very sensitive in detecting minuscule neuroelectric signals, but it is highly invasive and causes severe damage to the cell membrane. On the other hand, extracellular recording is non-invasive and very powerful in measuring large numbers of neurons, but it suffers poor signal-to-noise ratio and is unable to detect small synaptic neuroelectric potentials. This project will develop a novel electrical sensor -- nanopillar electrode arrays -- for highly-sensitive and non-invasive recording of neuroelectric activities. Nanopillars protruding from the planar surface will enhance the electric coupling between the neuron and the recording electrode. The new sensor will improve the detection sensitivity by two-orders of magnitude over the current extracellular recording technique. With the combined advantages of high sensitivity, non-invasiveness, and simultaneous multi-cell recording, the integrated device will enable new studies aimed to understand the mechanisms that govern how neurons in a network coordinate their activities in space and time and how those activities might encode external information.
The proposed research focuses on developing sensitive instrument to facilitate the quantitative measurements of signal propagation in neuronal networks. The education component of this proposal complements the research goal in (1) incorporating instrumentation fundamentals in an undergraduate laboratory course, (2) introducing research writing and presentation skills to undergraduate lab reports, and (3) mentoring under-privileged high school students in the research laboratory.
