NPR reports... In mice and one person, scientists were able to reproduce the altered state often associated with ketamine by inducing certain brain cells to fire together in a slow, rhythmic fashion... The finding also could be a step toward finding non-drug methods to control states of consciousness... The team used a tool called optogenetics, which Deisseroth helped invent. (As opposed to binaural beats, which use sound, optogenetics) uses light to control the firing of specific cells in the brain. As a result, the team was able to artificially generate this rhythm in the brains of mice.
Watch the Breath
Articles on mindfulness meditation.