Researchers attached electrodes to the heads of 23 children, just over half of whom had photosensitive epilepsy.

BBC: Scientists probe cartoon seizures

Photosensitive epilepsy is thought to affect between 0.5% and 0.8% of children aged between four and 14.

BBC: Scientists probe cartoon seizures

Though the phenomenon was observed before television, photosensitive epilepsy, as it is also called, has become far more common as TV has spread.

CNN: Japanese cartoon triggers seizures in hundreds of children

The Broadcasting Code states that broadcasters must take precautions to maintain a low-level risk to viewers who have photosensitive epilepsy and should give warning if they do go ahead with such lighting.

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