Leveraging integrated electronics in neuronal studies

Abstract

The development of treatments for neurological disorders is constrained by the absence of an experimental tool that can interrogate the mammalian brain in its most natural state. Using currently available electrical or optical methods, researchers can simultaneously record intracellular signals from only a couple dozen neurons. However, by adding a silicon integrated circuit (IC) chip to the experimental setup, researchers can communicate with several thousands of neurons at the same time, but only through extracellular signals and thus missing important details in the conversation with and between each neuron. In this work, I describe our pursuit of creating an electrophysiology system that records the intracellular behavior of a large neuronal network in parallel. This neuroelectronic interface utilizes an IC chip having a dense array of platinum black (PtB) electrodes across its surface, with each electrode boasting its own microscale amplifier. Combining these features with sustained electrode current injection, we can capture stable, sensitive intracellular signals at each electrode. The arrayed operation of the IC, a hallmark of silicon technologies, gives the parallelism that can benefit a broad range of neuronal research, including functional connectome mapping and high-throughput drug screening. Here, I elaborate on the lifecycle of our neuroelectronic interface from its fabrication to experimental use, focusing on how the IC chip is packaged for biochemical experiments and the advantages of adding PtB to each electrode. After this detailed account of its development, I highlight key experiments that demonstrate its contribution to brain research.