Self-induction of epileptic seizures by eyeclosure: incidence and recognition

Self-induction of epileptic seizures is generally regarded as a rarity, chiefly observed in patients of subnormal intelligence. During EEG recordings with open eyes in a consecutive series of 48 photosensitive patients, however, 13 subjects induced paroxysmal activity of seizures by eyeclosure with forced upward deviation of the eyes. Eyeclosure on command produced a different type of oculographic artefact and induced paroxysmal activity in only one subject. Two patients were of subnormal intelligence but all displayed psychiatric or psychosocial problems. The incidence of induced paroxysmal activity was reduced by reduction of ambient lighting. Eight patients admitted self-induction of seizures. We conclude that this phenomenon occurs more often than was previously supposed and can be recongnized by the recording in photosensitive patients of prolonged EEGs with eyes open and in a brightly lit environment.