Photosensitive epilepsies and photoconvulsive responses in Arabs. The occurrence of photosensitivity (PS) was examined in 327 Arabs greater than or equal to 15 years of age with epilepsy by intermittent photic stimulation (IPS). A control group of 192 nonepileptic Arabs greater than or equal to 15 years of age were also examined by IPS. Of the epileptic patients, 24 (7.3%) were photosensitive, an incidence comparable to that in whites in contradistinction to the reported rarity among African blacks. This finding indicates that environmental factors, particularly excessive sunshine, does not appear to influence the occurrence of PS among epileptic patients. The occurrence of PS among epileptic patients may depend more strongly on the presence of an epileptic syndrome known to have association with PS. 