Protocol for extracellular recordings in the external globus pallidus of the behaving/awake monkey

Extracellular recordings in behaving animals are useful for establishing associations between neuronal activity and behavior. Here, we describe how to record in the external globus pallidus (GPe) of monkeys engaged in a behavioral task. We detail the stereotaxic surgery for chamber and head-holder implantation, the post-operative MRI scan to ascertain the GPe coordinates and validate the position of the chamber, and the data collection. This protocol makes it possible to examine the electrophysiological features of GPe neurons in behaving monkeys. For complete details on the use and execution of this protocol, please refer to Katabi et al.¹