Frontal lobe seizures have greatly variable clinical and EEG manifestations depending on the origin and spread of the epileptogenic focus.
Seizures arising from the primary motor cortex and the supplementary motor area have been relatively well defined:
- Frontal seizures from the motor cortex
- Simple focal motor clonic or tonic-clonic seizures with or without Jacksonian march to neighboring motor regions. Hand and mainly thumb, face, and lips are preferentially affected (per the motor homunculus).
- Myoclonic seizures are unilateral or bilateral such as in epilepsia partialis continua of Kozhevnikov.
- Tonic postural motor with clonic movements.
- Frontal seizures from the supplementary sensorimotor area (SMA)
- Stereotyped hypermotor seizures of bilateral and asymmetric tonic posturing of limb girdles, often with contraversion of the eyes and head, vocalizations, or speech arrest.
- Brief for sec.
- Abrupt onset and termination.
- Nocturnal circadian distribution; rarely occur in awake states.
- High frequency, sometimes many per night.
- Lack of post-ictal confusion.
- Somatosensory and ill-defined auras (not epigastric) are common.
Epileptic seizures generated in frontal lobe regions other than the motor cortex and the SMA are less well specified. These are:
- Cingulate. Cingulate seizure patterns are complex partial with complex motor gestural automatisms at onset. Autonomic signs are common, as are changes in mood and affect. Gelastic seizures of frontal lobe origin emanate from this region.
- Anterior frontopolar. Anterior frontopolar seizure patterns include forced thinking or initial loss of contact and adversive movements of head and eyes, with possible progression including contraversive movements and axial clonic jerks and falls and autonomic signs.
- Orbitofrontal. The orbitofrontal seizure pattern is one of complex partial seizures with initial motor and gestural automatisms, olfactory hallucinations and illusions, and autonomic signs.
- Dorsolateral. Dorsolateral seizure patterns may be tonic or, less commonly, clonic with versive eye and head movements and speech arrest. Seizures characterized by unusual symptoms of "forced thinking" and "forced acts" usually emanate from the dorsolateral intermediate frontal lobe.
- Opercular. Opercular seizure characteristics include mastication, salivation, swallowing, laryngeal symptoms, speech arrest, epigastric aura, fear, and autonomic phenomena. Simple partial seizures, particularly partial clonic facial seizures, are common and may be ipsilateral. If secondary sensory changes occur, numbness may be a symptom, particularly in the hands. Gustatory hallucinations are particularly common in this area.
This page was adapted from:
The educational kit on epilepsies: The epileptic syndromes By C. P. Panayiotopoulos Originally published by MEDICINAE
21 Cave Street, Oxford OX4 1BA
First published 2006 and reprinted in 2007