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History
Early researches on selective auditory attention can be traced back to 1953, when Colin Cherry introduced the "cocktail party problem". At the time, air traffic controllers at the control tower received messages from pilots through loudspeakers. Hearing mixed voices through a single loudspeaker made the task very difficult. In Cherry's experiment, mimicking the problem faced by air traffic controllers, participants had to listen to two messages played simultaneously from one loudspeaker and repeat what they heard. This was later termed the dichotic listening task.

Though introduced by Cherry, Donald Broadbent is often regarded as the first to systematically apply dichotic listening tests in his research. Broadbent used the method of dichotic listening to test how participants selectively attend to stimuli when overloaded with them, deriving at his filter model of attention in 1958. In his model, Broadbent theorized that due to limited capacity, the human information processing system takes on the form of a "bottleneck" and performs an "early selection" before processing. Information first enters into an unlimited sensory buffer, out of which one is filtered out and passes through, while all others that are not selected quickly decays and are not understood. However, Broadbent's model contradicts with the cocktail party phenomenon as it predicts people would never respond to their names since unattended information is discarded before being processed.

A competing theory with Broadbent's early selection model would be Deutsch & Deutsch's late selection model proposed in 1963. The model theorizes that all information and input, wether intentionally or unintentionally, are attended to and processed for meaning. Later in the processing routine, just before information enters the short-term memory, a filter analyzes the semantic characteristics of the information, passing through stimuli containing relevant information while barring out unimportant content. This notion suggests that weak response to unattended stimuli comes from internal decision of information relevance, where more important stimuli are prioritized and enters the working memory first.

In 1964, Anne Treisman, a graduate student of Broadbent's, improved his theory and proposed her own attenuation model. In this model, unattended information is attenuated, tuned down compared to attended information, but still processed. For example, you are exposed to three other sources of sound in a coffee shop while ordering a drink (chatter, coffee brewer, music), Treisman's model indicates that you would still pick up on the latter three sounds while attending to the cashier, just that they would be more muffled as if their "volumes" were turned down. Treisman also suggests that there exists a threshold mechanism which words from the unattended stream can grab one's attention. Words of low threshold, higher level of meaning and importance, such as one's name and "watch out", redirects one's attention to where it is urgently required.