Intracranial event-related potentials

Abstract

An event-related potential (ERP) is any stereotyped EEG response to external or internal stimuli that is associated with cognitive or affective activity involved in processing the stimulus or preparing an action. Despite its long-lasting history human intracranial ERPs still represent an extremely useful tool for investigating many higher-level brain functions. They can provide us a better understanding of the cortical areas involved in certain cognitive or affective processes (spatial information) as well as of the sequence at which different cortical areas get involved (temporal information). This capacity definitely can be exploited in many basic research questions. The clinical use of iERPs in the presurgical evaluation of individual patients (as a predictor of postoperative memory deficit or as an index of the epileptogenic zone) is promising, but has to be further approved. Depth ERPs offer a window into the neuronal circuitry of mental processes in the human brain and serve as a touchstone for thoroughly evaluating the non-invasive techniques. Event-related fMRI and some other new sophisticated neuroimaging techniques complement, rather than replace, intracranial ERPs. The lecture will provide an update of the method and its use in the clinical neurophysiology.