Neural NoiseElectrocorticography (ECoG) records electrical activity directly from the surface of the cerebral cortex using electrode grids or strips placed subdurally. Compared to scalp eeg, ECoG provides substantially higher spatial resolution, broader usable bandwidth extending into high-gamma frequencies (70-200 Hz), and improved signal-to-noise ratio, while being less invasive than penetrating intracortical electrodes.
ECoG has a long clinical history in epilepsy surgery, where subdural grids are used to map seizure foci and eloquent cortex prior to resection. This clinical use has provided opportunities for bci-and-neural-decoding research, with epilepsy monitoring patients contributing to foundational studies of ECoG-based neural-decoding. High-gamma band activity recorded by ECoG has proven to be a robust and information-rich signal for decoding motor, speech, and cognitive processes.
The semi-invasive nature of ECoG positions it as a potential middle ground between scalp EEG and intracortical arrays for chronic BCI applications. Advances in thin-film electrode technology and minimally invasive implantation techniques are driving interest in long-term ECoG-based neural-interfaces for both clinical and assistive applications.