Network effects of deep brain stimulation

Abstract

The ability to differentially alter specific brain functions via deep brain stimulation (DBS) represents a monumental advance in clinical neuroscience, as well as within medicine as a whole. Despite the efficacy of DBS in the treatment of movement disorders, for which it is often the gold-standard therapy when medical management becomes inadequate, the mechanisms through which DBS in various brain targets produces therapeutic effects is still not well understood. This limited knowledge is a barrier to improving efficacy and reducing side effects in clinical brain stimulation. A field of study related to assessing the network effects of DBS is gradually emerging that promises to reveal aspects of the underlying pathophysiology of various brain disorders and their response to DBS that will be critical to advancing the field. This review summarizes the nascent literature related to network effects of DBS measured by cerebral blood flow and metabolic imaging, functional imaging, and electrophysiology (scalp and intracranial electroencephalography and magnetoencephalography) in order to establish a framework for future studies.

Keywords: deep brain stimulation; electrocorticography; magnetoencephalography.

Fig. 1.

Schematic of network modulation by deep brain stimulations (DBS) in 3 major targets. Brain regions modulated by DBS of the subthalamic nucleus (STN; orange), thalamus (red), and nucleus accumbens (yellow) are indicated (in the contralateral hemisphere for visual clarity). S1, primary sensory cortex; M1, primary motor cortex; SMA, supplementary motor area; PMC, premotor cortex; DLPFC, dorsolateral prefrontal cortex; ACC, anterior cingulate cortex; PHG, parahippocampal gyrus.