Bilateral sound is a type of bilateral stimulation used in eye movement desensitization and reprocessing (EMDR) in the same manner as eye movement. It has been reported to enhance visualization and hypnosis, but this has received little attention in research. Essentially, the sound moves back and forth across the stereo field at a steady rhythm. In this regard, bilateral sound has been used in commercial recordings, and has been applied manually with the use of an electronic metronome or other means. Controversies regarding this and other forms of bilateral stimulation are discussed in the article on EMDR.