Ramirez suffered two head injuries at age five where he was knocked unconscious, one of which he was hit by a swing and another in which a dresser drawer fell on him, which doctors say caused his epilepsy later on as a child. He had his first seizure in fifth grade and subsequently suffered from one or two dozen petite mal seizures every month along with a few grand mal seizures until he entered his teens. Later he was diagnosed with Temporal Lobe Epilepsy. His biggest disappointment was being thrown off the football team because of his seizures. Due to the epilepsy he also suffered from recurring vivid dreams where monsters were chasing him and once at seven had visions of monsters running around his yard. (Source: http://reviewessays.com/print/Richard-Ramirez/24310.html)
There is reason to believe Temporal Lobe Epilepsy may have played a role in his murders, since the temporal lobe is responsible for rationality. Sufferers typically have extreme moods and poor impulse control, such as Vincent Van Gogh, who was prone to fits of madness as well as depression. Van Gogh ran from the house during a thunderstorm as a result of an argument with his family. Other famous sufferers include Sylvia Plath and Edgar Allan Poe.