*binaural vs. dichotic listening
Both of these terms refer to the ability of selective attention or the ability to attend to one thing and ignore others. Dichotic listening occurs when two messages are presented to separate ears, while binaural listening is when two messages are presented to both ears simultaneously.
Colin Cherry used these two types of listening in his famous experiment of the Cocktail Party Problem in the 1950's. In his experiment he mostly used dichotic listening. He would have participants would be presented with messages either by means of dichotic or binaural listening. For dichotic they would be presented with one message in the left year and another message to the right ear. They would then be asked to pay attention to one message (attended message) and ignore the other (unattended message) and to shadow or repeat the attended message out loud.
Donald Broadbent also used dichotic and binaural listening techniques in his experiments that demonstrated his filter model known as the early-selection model. Broadbent selection model helped to explain how selection is actually achieved. According to Broadbent’s early selection model, attention occurs first than pattern recognition. He was able to show this through experiments that included both dichotic and binaural listening that showed participants were able to identify physical characteristics (where attention) to shadow messages, but not semantic or meaning characteristics (what exactly something is). Physical characteristics such as location were better identified in dichotic listening, while sound or pitch (male vs. female voice) were better identified in binaural tasks. Semantic characteristics such as language or meaning of messages were unable to be identified by participants.