Basic principles of deep brain and cortical stimulation

Electrical stimulation of the nervous system is utilized to modify neuronal activity and alleviate symptoms of neurological or behavioural disorders. There are multiple applications of electrical stimulation, ranging from peripheral functional electrical stimulation for post-spinal cord injury paralysis to deep brain stimulation for movement disorders and emerging indications. This chapter focuses on the basic principles of deep brain and cortical stimulation. Stimulation parameters and electrode configurations can be selected in such a fashion as to improve the efficacy of stimulation and reduce undesirable side effects. Although motor cortical stimulation was pioneered for the management of central post-stroke pain, recent studies have investigated the effects of cortical stimulation on motor recovery after stroke and depression. Several factors can influence the outcome of cortical stimulation such as the thickness of cerebrospinal fluid layer.