Electrode location determines which brain regions contribute most directly to the recorded signal. Contacts on the cortical surface sample activity near the cortex, whereas electrodes within brain tissue capture signals from targeted internal regions. This spatial specificity allows investigators to relate electrical changes to particular neural areas, improving interpretation of seizures, functions, and circuit activity.
Because the electrodes are positioned on or within the brain rather than separated from it by the scalp, intracranial electroencephalography can measure activity from selected regions with strong spatial and temporal detail. Scalp EEG remains useful for broader electrical monitoring, while intracranial recordings complement it when researchers or clinicians need more precise information about targeted brain areas.
The electrodes detect voltage changes associated with synchronized neuronal activity. These coordinated changes create measurable electrical patterns that can be examined across targeted brain regions and over time. Their relationship to synchronization helps investigators study normal neural circuits as well as abnormal activity, including patterns associated with epilepsy and other pathological brain processes.
Precise placement links recorded voltage changes to specific cortical or intracerebral locations. In epilepsy evaluation, this localization helps identify seizure onset zones, the regions associated with the beginning of a seizure. The same spatial relationship supports investigation of pathological activity by showing where relevant electrical patterns occur within the brain.
The essential workflow is to place electrodes on the cortical surface or within selected brain tissue, record voltage changes from those contacts, and interpret the activity in relation to the targeted regions. The resulting measurements can then be evaluated for seizure-related patterns, functional responses, neural-circuit activity, cognition, or other pathological electrical changes.
Clinicians use intracranial electroencephalography to examine electrical activity from targeted brain regions when identifying a seizure onset zone is important for epilepsy evaluation. Direct recordings provide localized information that can complement scalp EEG. This information contributes to personalized neurosurgical care by relating abnormal activity to specific areas under consideration.
Before surgery, recordings can help map language, sensory, and motor functions by examining activity in targeted brain regions. This functional information complements seizure localization and supports decisions about how neural areas relate to planned care. In neuroscience, the approach also connects electrical activity with cognition and neural-circuit organization.
Beyond seizure evaluation, intracranial electroencephalography supports studies of neural circuits, cognition, and pathological brain activity. Its detailed recordings allow researchers to examine electrical activity in relation to targeted regions and brain functions. These applications extend the method from clinical localization to fundamental neuroscience and help advance personalized approaches to neurosurgical care.