What does "interictal" activity refer to in an EEG context?

In the context of EEG (electroencephalogram) monitoring, "interictal" activity refers specifically to brain activity that is recorded between seizures. This term is derived from the prefix "inter-" meaning "between" and "ictus," which refers to a seizure or convulsion.

During the interictal period, the brain is not experiencing an active seizure but may exhibit various types of electrical activity, including normal patterns or potential abnormalities that could indicate conditions such as epilepsy. This can help clinicians in diagnosing and managing seizure disorders, as the interictal activity provides crucial information about the overall electrical activity of the brain between episodes of seizure activity.

This understanding is vital for interpreting EEG results, as the characteristics of interictal activity can play a significant role in differentiating between various types of epilepsy and guiding treatment decisions. The other concepts, such as brain activity during a seizure or specific sleep activity, do not accurately define what interictal activity entails.