Clinical and electroencephalogram characteristics of pilomotor seizures

Background Piloerection, a physiological response to cold or emotional stimuli, is a rare autonomic manifestation of epileptic seizures. The literature on pilomotor seizures remains limited, with its anatomical correlates and electrophysiological mechanisms poorly understood. Methods We conducted a retrospective analysis of 13 patients with pilomotor seizures identified from 8,482 individuals monitored at Epilepsy Center of West China Hospital. Demographic data, seizure characteristics, neuroimaging, and neurophysiological findings were analyzed to determine the epileptogenic zone and associated etiologies. Results Our case series revealed a strong predilection for temporal lobe origin (11/13 patients), with distinctive ictal EEG patterns including rhythmic delta activity. Piloerection was consistently accompanied by other autonomic or psychic symptoms. Most patients responded favorably to anti-seizure medications. Conclusion Pilomotor seizures are associated with temporal lobe epilepsy and are characterized by distinctive ictal EEG patterns, particularly rhythmic delta activity, and are frequently associated with specific etiologies such as autoimmune encephalitis.