In PNES, what does EEG typically show during events?

• A. During PNES events, EEG shows continuous spike-and-wave discharges.
• B. During PNES events, EEG shows no epileptiform activity.
• C. EEG is not helpful in PNES evaluation.
• D. PNES EEG is identical to epileptic seizures.

Answer: (B)

In PNES, during an event the brain does not generate the epileptic electrical patterns seen in true seizures. So the EEG typically remains without epileptiform discharges—no spikes, spike‑and‑waves, or rhythmic epileptic activity. What you might see instead are normal background rhythms or non-epileptiform activity, with movement or other signals often creating artifact on the tracing.

This is why video-EEG monitoring is so helpful: if a clinical seizure looks convincing but the EEG shows no epileptiform activity during the event, PNES becomes a likely diagnosis. It’s also why stating that EEG is identical to epileptic seizures or that EEG shows continuous epileptic discharges during PNES wouldn’t fit the pattern of PNES. And claims that EEG isn’t useful in PNES evaluation aren’t accurate—EEG (especially with video) is a key tool to distinguish PNES from epileptic seizures.