Psychedelia in music (or also psychedelic music, less formally) is a term that refers to a broad set of popular music styles, genres and scenes, that may include psychedelic rock, psychedelic folk, psychedelic pop, psychedelic soul, psychedelic ambient, psychedelic trance, psychedelic techno, and others. Psychedelic rock is also commonly called acid rock. Psychedelia can occur in almost every genre of music, including classical Western art music. Despite roots which extend far back in music history, the term is most commonly applied to music made beginning around 1966, when psychedelic drugs gained in popularity with both the public and popular music scene, and subsequent music influenced by that period. Broadly speaking, psychedelia generally employs non-naturalistic production techniques, which can include extreme stereo spatialization, reverb, reversed, phased, or flanged tape recordings, extensive editing, and extended improvisation. The music is often intended to have a disorienting or destabilizing effect, or to otherwise act on the listeners' sense of "normalcy". .