Auditory illusion


Auditory illusions are false perceptions of a real sound or outside stimulus. These false perceptions are the equivalent of an optical illusion: the listener hears either sounds which are not present in the stimulus, or sounds that should not be possible given the circumstance on how they were created.
Auditory illusions highlight areas where the human ear and brain, as organic survival tools, differentiate from perfect audio receptors; this shows that it is possible for a human being to hear something that is not there and be able to react to the sound they supposedly heard.

Causes

Sounds that are found in words are called embedded sounds, and these sounds are the cause of some auditory illusions. A person's perception of a word can be influenced by the way they see the speaker's mouth move, even if the sound they hear is unchanged. For example, if someone is looking at two people saying "far" and "bar", the word they will hear will be determined by who they look at. If these sounds are played in a loop, the listener will be able to hear different words inside the same sound. People with brain damage can be more susceptible to auditory illusions and they can become more common for that person.

Examples

There are a multitude of examples out in the world of auditory illusions. These are examples of some auditory illusions:
According to Purwins, auditory illusions have been used effectively by various composers, e.g. Beethoven, Berg, Krenek, Ligeti, Honegger, and Stahnke.