Progress of microelectrode arrays for brain signal recordings

The recording technique of microelectrode arrays provides an ideal means for obtaining the large amount of neuronal electric activity, simultaneously. The technique has significant impacts on the intensive investigations for the mechanisms of neurons and their networks, as well as on the development of novel neural prosthetic and therapeutic devices. Utah microelectrode and Michigan microelectrode are two major types of rapidly developed electrode arrays that have been used in neural signal detections in-vivo. In this paper, the manufacture, the structure, the feature and the application of both types of electrode are compared. The principles and methods for the detection and analysis of neural field potentials and unit activity by using the electrode arrays are described. In addition, the challenges and further development in electrode fabrication, in neural signal recording and in signal processing are discussed.