Recordings of the hippocampal field potentials and unit activity by using linear silicon electrode array

The rapid development of silicon microelectrode arrays provides an ideal means for the study of spatio-temporal features of neuronal activity in the brain. The stability of the linear silicon electrode array (LSEA) in recording neuronal potentials and its validity in recording unit activity are investigated. The experimental results showed that during the recording of field potentials in the hippocampal CA1 region of anesthetized rats, upward and downward movements of the recording probe for a distance of 200 μ did not affect the orthordromic and antidromic evoked potentials significantly. The data indicated that the probe movements caused very small damage to the neurons, and the recording was stable. The contact sites that located in the pyramidal cell layer acquired CA1 neuronal unit activity validly. Different types of unit activity from independent neurons were easily distinguished in epochs of recording from a same recording site. These results demonstrated the features of the LSEA, including the facility of probe manipulation, the stability of recording and the abundance of data acquirement. The data will be helprul to the researchers involved in the application of microelectrode array for neuroscience researches.