What is Photosensitive Epilepsy / Photosensitive Seizure Disorders?

An epileptic seizure is a sudden and brief surge of electrical activity in the brain, due to abnormal, excessive or synchronous neuronal activity. Seizures are a symptom of many diseases of the brain, collectively called epilepsy. The most common type of seizure is convulsive, with the body muscles contract and relax rapidly and repeatedly, thus resulting in an uncontrolled shaking of the body. In addition, the generalized seizures involve a loss of consciousness. In a complex partial seizure a person may appear confused or dazed and cannot respond to questions or direction.

People with a specific condition, called photosensitive epilepsy (~3-5% of people with epilepsy) may suffer a seizure when frequency of flashing light of computer screens (or monitors), or of content being rendered, is in the range of 3 to 50 flashes per second. Furthermore, people are even more sensitive to red flashing than to other colors.

Video explanation of photosensitive epilepsy:

  1. Seeker – How video games can cause seizures.
  2. Howcast – What is photosensitive epilepsy?

Web Page Evaluation Tool 


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  2. Seizures, WCAG2.0. Url:
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  4. P.A. Howarth. Potential hazards of viewing 3-D stereoscopic television, cinema and computer games: a review. Ophthalmic and Physiological Optics, 31(2), 2011. DOI: 10.1111/j.1475-1313.2011.00822.x.
  5. A.M. da Silva, B. Leal. Pthotosensitivity and epilepsy: current concepts and perspectives – a narrative review. Seizure, 50, 2017, pp.209-218. DOI: 10.1016/j.seizure.2017.04.001.
  6. L. Carreira, N. Rodrigues, B. Roque, M.P. Queluz. Automatic detection of flashing video content. In Proceedings of 2015 Seventh International Workshop on Quality of Multimedia Experience (QoMEX), 26-29 May 2015. DOI: 10.1109/QoMEX.2015.7148104.
  7. J. Sproul, J. MacCallum, S. Ledger. Screens and teens with migraines: visually sensitive learners in contemporary digital classroom. Disability & Society, 32(8), 2017. DOI: 10.1080/09687599.2017.1330455.