High Resolution Neuro-Electronic Interface System for Electrophysiological Experiments

Neil Joye, Microelectronic Systems Laboratory, EPFL-STI-IMM-LSM, Lausanne

Abstract: The study of neural cellular function and response has been used for decades to better understand the operation of the brain. As technology has improved, neuron scientists have shown increased interest in in-vitro experimentation methodology to support advanced studies of the brain and its neurons operation. Using microelectrode arrays (MEAs), it is now possible for populations of neural cells to be examined simultaneously, thereby providing better insight into the functionality and interconnectivity of cellular networks. Traditionally, MEAs encompass a passive MEA chip with external signal conditioning electronics and a system control that is realized of discrete, off-chip components. Each individual electrode needs to be wired to external electronics, which limits the size of the array. Recently, it has been shown that CMOS electronics overcomes the drawbacks of traditional MEAs. CMOS electronics offers on-chip amplification and multiplexing, which enables the integration of a large number of electrodes. However, there are still some important challenges that need to be solved. Due to micro-fabrication and electrical issues, it is still very difficult to fabricate electrode arrays with high spatial resolution.

Therefore, a new approach based on three-dimensional electrodes is being developed in order to increase the electrical coupling between the neural cells and the electrode array. Thus, MEAs with higher spatial resolution can be achieved. The manufacturing process of the three-dimensional electrodes and the modeling of the neuron-electronic interface will be presented.

About the speaker: Neil Joye received M.Sc (2005) degree in Electrical Engineering from the Ecole Polytechnique Fédérale de Lausanne (EPFL). In his master thesis, he has investigated different applications of neuronmorphic CMOS circuits under the supervision of Prof. Yusuf Leblebici, head of the Microelectronic Systems Laboratory (LSM) and Prof. Tetsuya Asai of the Laboratory of Advanced LSI Engineering, Hokkaido University, Japan. Since 2006, he is a Ph.D student in EPFL/LSM, investigating high resolution MEAs for electrophysiological experiments.

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