Generally associated with the 1960s and the mind-expanding drug LSD. There are many earlier examples of artists taking drugs in order to heighten their awareness and enlarge their mental vision, but it was the hallucinatory effects of LSD that had such a powerful effect on artists. Day-glo and anti-naturalistic in colour, Psychedelic art often contained swirling patterns, erotic imagery and hidden messages, all aiming to refer to the changing states of consciousness while under the influence of the drug. Much of the art grew out of the hippy community in San Francisco, in particular the artists Stanley Mouse, Rick Griffin and Alton Kelley who were commissioned by the rock promoter Bill Graham to produce posters for the bands The Grateful Dead, Jimi Hendrix and The Big Brother Holding Company.