Case report: Remote neuromodulation with direct electrical stimulation of the brain, as evidenced by intra-operative EEG recordings during wide-awake neurosurgery

ObjectiveTo identify which cortical regions are associated with direct electrical stimulation (DES)–induced alteration of breathing significant enough to impair pulse oximetry (SpO2).MethodsEvolution of SpO2 after 1,352 DES was analyzed in 75 patients with refractory focal epilepsy who underwent stereo-EEG recordings. For each DES, we assessed the change in SpO2 from 30 seconds prior to DES onset to 120 seconds following the end of the DES. The primary outcome was occurrence of stimulation-induced transient hypoxemia as defined by decrease of SpO2 ≥5% within 60 seconds after stimulation onset as compared to pre-DES SpO2 or SpO2 nadir <90% during at least 5 seconds. Localization of the stimulated contacts was defined according to MarsAtlas brain parcellation and Freesurfer segmentation.ResultsA stimulation-induced transient hypoxemia was observed after 16 DES (1.2%) in 10 patients (13%), including 6 in whom SpO2 nadir was <90%. Among these 16 DES, 7 (44%) were localized within the perisylvian cortex. After correction for individual effects and the varying number of DES contributed by each person, significant decrease of SpO2 was significantly associated with the localization of DES (p = 0.019).ConclusionThough rare, a significant decrease of SpO2 could be elicited by cortical direct electrical stimulation outside the temporo-limbic structures, most commonly after stimulation of the perisylvian cortex.

Download Full-text

Experiential phenomena elicited by direct electrical stimulation of the brain

International Journal of Psychophysiology ◽

10.1016/s0167-8760(97)85560-2 ◽

1997 ◽

Vol 25 (1) ◽

pp. 77

Author(s):

Eric Halgren ◽

Patrick Chauvel

Keyword(s):

Electrical Stimulation ◽

Direct Electrical Stimulation ◽

The Brain ◽

Stimulation Of

Download Full-text

Understanding Variable Motor Responses to Direct Electrical Stimulation of the Human Motor Cortex During Brain Surgery

Frontiers in Surgery ◽

10.3389/fsurg.2021.730367 ◽

2021 ◽

Vol 8 ◽

Author(s):

Daniel M. Aaronson ◽

Eduardo Martinez Del Campo ◽

Timothy F. Boerger ◽

Brian Conway ◽

Sarah Cornell ◽

...

Keyword(s):

Electrical Stimulation ◽

Motor Cortex ◽

Motor System ◽

Neurosurgical Procedures ◽

Direct Electrical Stimulation ◽

Human Motor Cortex ◽

Motor Responses ◽

Human Motor ◽

The Brain ◽

Stimulation Of

Direct electrical stimulation of the brain is the gold standard technique used to define functional-anatomical relationships during neurosurgical procedures. Areas that respond to stimulation are considered “critical nodes” of circuits that must remain intact for the subject to maintain the ability to perform certain functions, like moving and speaking. Despite its routine use, the neurophysiology underlying downstream motor responses to electrical stimulation of the brain, such as muscle contraction or movement arrest, is poorly understood. Furthermore, varying and sometimes counterintuitive responses can be seen depending on how and where the stimulation is applied, even within the human primary motor cortex. Therefore, here we review relevant neuroanatomy of the human motor system, provide a brief historical perspective on electrical brain stimulation, explore mechanistic variations in stimulation applications, examine neurophysiological properties of different parts of the motor system, and suggest areas of future research that can promote a better understanding of the interaction between electrical stimulation of the brain and its function.

Download Full-text