Many have experienced moments of blinding light, when mind and body dissolved and a flood of joy welled up and erupted in laughter. Yamada Roshi, a great Japanese Zen teacher with whom I studied in 1973, saw the image of the sky opening a mouth that hooted with world-annihilating laughter as he achieved kensho on the commuter train back home to Kamakura . What is happening in the brain during such experiences? We will review the neurophysiological theories that have tried to explain these great moments. Some claim global field synchrony, others see sudden shifts in the orientation centers of the parietal lobe, and some like James Austin find a process of etching away ego structures until the whole house of cards collapses. My own view is that none of these explanations is adequate and that quantum phenomena, or the quasi-quantum field structures posited by Roy John, must be involved. Enlightenment is an event prepared for in ways that have been suggested by the authors mentioned above, but when it happens something entirely new takes place, something that comes from the depths of the mind where quantum processes act in the service of consciousness. To make this idea plausible I will discuss some recent ideas of Roger Penrose, Stuart Hameroff