A Method for Chronic Registration of Brain Cortical Electrical Activity in Rats

Electrocorticogram registration and analysis (electrocorticography, ECoG) is widely used in small-animal biomedical research. To date, a considerable number of techniques for ECoG electrode manufacture and implantation have been proposed. Many commercial manufacturers of neurophysiological equipment offer a wide variety of such electrodes, ranging from the simple needle or concentric ones to flexible microelectrode arrays. However, due to several reasons, neurophysiological methods (including ECoG) are much more rarely used in practical research than, for example, behavioural testing or molecular genetics. In this paper, we propose a simple and straightforward method for rat ECoG electrode assembly and implantation. Brain electrical activity registration in laboratory animals can be used to evaluate the functional state of the central nervous system, the effects of pharmacological interventions, and sensory system function by recording visual and somatosensory evoked potentials. The method we propose can be employed in neuropharmacological as well as neurophysiological experiments and may prove a valuable addition to the more conventional biomedical research techniques.