The exact mechanisms underlying dysfunction of the basal ganglia that lead to Parkinson’s disease (PD) remain unclear. According to the standard model of PD, motor symptoms result from abnormal neuronal activity in dysfunctional basal ganglia, which can be recorded in human basal ganglia structures as functional neurosurgery for PD provides a unique opportunity to record from these regions. Microelectrode and local field potential recordings studies show alterations exist in basal ganglia nuclei as well as in the motor thalamus. Lesioning or stimulation of the basal ganglia results in significant improvement of PD symptoms, supporting the view that basal ganglia–thalamocortical circuits abnormality is important in parkinsonism generation. Different patterns of oscillatory neuronal activity plus changes in firing rate are associated with different parkinsonian motor subtypes. We present recordings of basal ganglia activity obtained with microelectrode recordings in parkinsonian patients, providing pathophysiology insight.

This chapter describes the techniques used in electrophysiology and electrochemistry and explains the figures derived from these methods. The introduction describes how neurons can be modeled as electrical circuits and explains different preparations of electrophysiological samples, the common recording configurations, and the equipment used with these techniques. The techniques are divided into a few major categories: passive neuronal properties, action potential analysis, synaptic events including paired pulse ratios and long-term potentiation, current-voltage plots, and electrochemistry techniques such as fast scan cyclic voltammetry and amperometry.