Dr. Andrew Newberg of the University of Pennsylvania scanned the brains of long-term practitioners of Buddhism while they were meditating and compared them with images taken when they were not. Newberg saw that blood flow to the posterior superior parietal lobe decreased during meditation. This area of the brain determines the boundaries of one’s body in relation to the environment and allows us to navigate a complex three-dimensional world without bumping into things. “We know that the posterior superior parietal lobe plays that particular role because there are patients with damage in this same region who literally cannot move around without falling,” Newberg reports. “They’ll miss the chair they intended to sit on, and generally have a fuzzy understanding of where their body ends and the rest of the universe begins.” He says that when people have spiritual experiences and feel they become one with the universe and lose their sense of self, it may be because of what is happening in that area of the brain. “If you block that area, you lose that boundary between the self and the rest of the world.” Were the Buddhist meditators merely experiencing an odd side effect of submitting their brains to unusual conditions?

Dr. Michael Persinger, a professor of neuroscience at the Laurentian University in Canada, studied 1,018 meditators in 1993 and found that meditation can bring on symptoms of complex partial epilepsy such as visual abnormalities, hearing voices, feeling vibrations, or experiencing automatic behaviors such as narcolepsy. Note that epileptic patients who suffer from seizures in the temporal lobes have auditory or visual hallucinations, which they often interpret as mystical experiences. Some are convinced that they conversed with God.