Psychedelic art is any art that has been inspired by the experiences and hallucinations caused by psychoactive drugs like LSD. The term psychedelic was first coined by Humphry Osmond and means mind manifesting. Technically, all art could be referred to as psychedelic, but usually when we use the term we mean the style of art that developed in the 1960s. The art movement was a visual response to the psychedelic rock music of the time.
There are some key features of psychedelic art. It uses fantastic, surreal and metaphysical subject matter. It uses bright colors, and can use very contrasting colors. It uses fractal, paisley, and kaleidoscope type patterns. Some pieces of psychedelic art use a style called Horror vacui style, which when the whole space is filled with detail. Other pieces morph objects, themes and on occasion collage. There can also be spirals, circles, diffraction patterns and motifs. Some posters repeat the motifs, others use optical illusions. Psychedelic art and posters can also use lettering and typography to complete its effect.