Goosebumps (Piloerection) Are the Seizure Itself, Not a Warning
Piloerection episodes represent autonomic simple partial seizures—they are the ictal event itself, not merely an aura preceding a larger seizure. 1, 2
Understanding Pilomotor Seizures
Pilomotor seizures are a distinct subtype of simple partial seizures with autonomic manifestations originating from temporal lobe epileptic activity. 1 The goosebumps themselves constitute the seizure discharge, though they may progress to more complex seizure activity.
Key Clinical Characteristics
Piloerection spreads in a "Jacksonian march" pattern, typically remaining ipsilateral to the epileptic focus but occasionally spreading contralaterally. 1
These episodes are often accompanied by other autonomic symptoms including cold shivers, cold sweats, and ictal tachycardia. 1, 3, 4
Pilomotor seizures may occur as isolated simple partial events or progress to complex partial seizures with impaired awareness, and rarely to secondary generalization. 1
The episodes can occur with remarkable frequency—in documented cases, pilomotor seizures have been recorded at rates of one every 15 minutes during acute repetitive phases. 4
Anatomical Origin and Lateralization
Temporal lobe origin is the consistent anatomical substrate, with epileptic generators localized to mesial temporal structures. 1, 2, 4
Left hemispheric predominance has been observed in patients presenting with cold shivers and goosebumps as principal ictal manifestations. 3
Both symptomatic and idiopathic etiologies occur, including structural lesions (glioblastoma, meningioma, hippocampal sclerosis, arteriovenous malformations, trauma) and genetic cases with positive family history. 1, 2
Diagnostic Approach
Video-EEG monitoring is essential to capture and characterize these brief autonomic events, as interictal EEG may show temporal foci but ictal recording confirms the diagnosis. 1, 4
MRI with epilepsy protocol is the imaging modality of choice to identify structural temporal lobe pathology, as focal seizures have considerably higher neuroimaging yields than generalized seizures. 5
Detailed history from both patient and witnesses is critical, as pilomotor seizures are frequently underestimated or misinterpreted by patients and physicians alike. 1
Treatment Implications
Parenteral benzodiazepines (lorazepam) effectively terminate acute repetitive pilomotor seizures, as demonstrated in documented cases of pilomotor status epilepticus. 4
Carbamazepine provides effective chronic seizure control for pilomotor seizures, consistent with its first-line status for focal-onset epilepsy. 1
Phenytoin is an alternative first-line agent for focal seizures when carbamazepine is contraindicated. 6, 1
Critical Clinical Pitfalls
Do not dismiss isolated piloerection as anxiety or a non-epileptic phenomenon—when stereotyped and recurrent, these episodes warrant full epilepsy evaluation. 1
Do not assume goosebumps are merely an aura—they represent the seizure discharge itself, though they may herald progression to more complex seizure activity. 1
Recognize that pilomotor seizures can present as simple partial status epilepticus, requiring urgent parenteral antiepileptic treatment. 1, 4
A normal interictal EEG does not exclude the diagnosis—video-EEG monitoring to capture actual episodes may be necessary for definitive diagnosis. 5, 7