Audio-analgesia is the relief of pain using white noise or music without pharmacological agents. It was first introduced by Gardner and Licklider in 1959. There are many studies of its use in dental, obstetric, and palliative care contexts. The most recent review reports mixed results for effectiveness. is similar to breathing exercises during cramps before administration of epidurals. It has also been suggested that music may stimulate the production of endorphins and catecholamines.