TOWARDS A VERSATILE SYSTEM FOR ADVANCED NEURONAL RECORDINGS USING SILICON MULTISITE MICROELECTRODES

he current understanding of how the nervous system functions is based on numerous observations of the behaviour of single units or a small ensemble of units correlated to some external stimulation or behavioural event [1]. However, the processing power of the nervous system lies in its network and interconnections [2]. Thus, the key to understand the nervous system is to make simultaneous observations of the activity of numerous cells forming acting and responding networks [3-5]. The obviously resulting need for a high number of extracellular recording sites placed in close proximity to those cells within the brain is a well know fact [6]. However, even the most up-to-date techniques are still depending on the use of singular microelectrodes or micro-wires to be implanted into the brain area under observation [7]. The use of bundled (stereo- or tetrodes) or brush-like arranged microelectrode-arrays helps to increase the number of recording sites, however, long and tedious implantation surgeries are still mandatory [8]. It appears therefore highly desirable to increase the productivity of a single surgery by implanting a multitude of recording sites at once [9]. Our project VSAMUEL set out to bring current micro-machining technologies to work and to produce not only batchfabricated multi-site microelectrode arrays, but high quality data acquisition systems as well.