Four patients had prolonged, sensory, simple partial seizures (SPS), lasting up to several days, without associated behavioural impairment. In three patients, the SPS often occurred as a prolonged "aura" before a more overt seizure. Descriptions included: "butterflies", rising epigastric sensation; "a thought in the stomach", and an olfactory sensation. Seizure localisation was frontal in one case, temporal in two cases and uncertain in one case. These sensations may represent an under-reported form of continuous, focal seizure activity, which arises from various cerebral regions.