Development of a planar microelectrode array offering long-term, high-resolution neuronal recordings

Abstract

All nervous system functions, ranging from simple reflexes to learning and memory, rely on networks of interconnected brain cells called neurons, which initiate and convey electrical information. Monitoring neuronal activities of a large neuronal ensemble, non-invasively and over an extended time period, is pivotal for understanding all brain functions. A variety of neuro-electronic interfaces now allow monitoring of neuronal and ion channel activities. These neuronal monitoring devices are however limited vis-à-vis their efficacy, fidelity and longer-term recording capabilities. Here we report on a novel microelectrode array technology that allows for the detection and characterization of neural activity from individual cells and networks, over long periods of time and with a higher signal-to-noise ratio than commercially available devices.

Our in-house development of planar microelectrode arrays has focused on modifying design parameters and fabrication techniques to improve their performance. One such device, the Soma-Soma Chip (SS-Chip), allows us to record activity from single and paired cells (pre- and post-synaptic neurons) continuously over extended periods of time with a signal-to-noise ratio higher than similar standard devices. This allows for the analysis of neural activity, which can help to characterize firing patterns of neurons at various developmental-stages. Of particular importance is the precise “signatures” of neuronal firing pattern that offers a unique opportunity to decipher how neuronal activity influences brain network connectivity. Our data also underscore the importance of further development of novel microelectrode array technologies. These developments will provide novel tools and open new research opportunities critical for understanding the fundamental cellular and network properties underlying network activity under both normal and disease conditions.