Auditory illusions are

illusions An illusion is a distortion of the senses, which can reveal how the mind normally organizes and interprets sensory stimulation. Although illusions distort the human perception of reality, they are generally shared by most people. Illusions may ...

of real sound or outside stimulus. These false perceptions are the equivalent of an

optical illusion In visual perception, an optical illusion (also called a visual illusion) is an illusion caused by the visual system and characterized by a visual perception, percept that arguably appears to differ from reality. Illusions come in a wide varie ...

: 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. Humans are fairly susceptible to

, despite an innate ability to process complex stimuli. Confirmation bias is believed to be largely responsible for the inaccurate judgments that people make when evaluating information, given that humans typically interpret and recall information that appeals to their own biases. Amongst these misinterpretations, known as illusions, falls the category of auditory illusions. The brain uses multiple senses simultaneously to process information, spatial information is processed with greater detail and accuracy in vision than in hearing. Auditory illusions highlight areas where the human ear and

brain The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for ...

, 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. When someone is experiencing an auditory illusion, their brain is falsely interpreting its surroundings and distorting their perception of the world around them.

Causes

Many auditory illusions, particularly of music and of speech, result from hearing sound patterns that are highly probable, even though they are heard incorrectly. This is due to the influence of our knowledge and experience of many sounds we have heard. In order to prevent hearing echo created by perceiving multiple sounds coming from different spaces, the human auditory system relates the sounds as being from one source. However, that does not prevent people from being fooled by auditory illusions. 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.

In music

Composers have long been using the spatial components of music to alter the overall sound experienced by the listener. One of the more common methods of sound synthesis is the use of combination tones. Combination tones are illusions that are not physically present as sound waves, but rather, they are created by one's own neuromechanics. According to Purwins, auditory illusions have been used effectively by the following:

Beethoven Ludwig van Beethoven (baptised 17 December 177026 March 1827) was a German composer and pianist. He is one of the most revered figures in the history of Western music; his works rank among the most performed of the classical music repertoire ...

(Leonore Overture),

Berg Berg may refer to: People *Berg (surname), a surname (including a list of people with the name) * General Berg (disambiguation) * Berg Ng (born 1960), Hong Kong actor * Berg (footballer, born 1963), Ninimbergue dos Santos Guerra, Brazilian footba ...

(''

Wozzeck ''Wozzeck'' () is the first opera by the Austrian composer Alban Berg. Composed between 1914 and 1922, it premiered in 1925. It is based on the drama '' Woyzeck'', which German playwright Georg Büchner left incomplete at his death. Berg attende ...

''), Krenek (''Spiritus Intelligentiae, Sanctus''), Ligeti ( Études),

Violin Concerto A violin concerto is a concerto for solo violin (occasionally, two or more violins) and instrumental ensemble (customarily orchestra). Such works have been written since the Baroque period, when the solo concerto form was first developed, up thro ...

, Double Concerto, for flute, oboe and orchestra), Honegger ('' Pacific 231''), and Stahnke (Partota 12).

Examples

There are a multitude of examples out in the world of auditory illusions. These are examples of some auditory illusions: *

Binaural beats In acoustics, a beat is an Interference (wave propagation), interference pattern between two sounds of slightly different frequency, frequencies, ''perceived'' as a periodic variation in amplitude (music), volume whose rate is the Difference (math ...

* The constant spectrum melody * Deutsch's scale illusion *

Electronic voice phenomenon Within ghost hunting and parapsychology, electronic voice phenomena (EVP) are sounds found on electronic recordings that are interpreted as spirit voices. Parapsychologist Konstantīns Raudive, who popularized the idea in the 1970s, described E ...

: a special case of auditory pareidolia *

Franssen effect The Franssen effect is an auditory illusion where the listener incorrectly localizes a sound. It was found in 1960 by Nico Valentinus Franssen (1926–1979), a Dutch physicist and inventor. There are two classical experiments, which are related ...

* Glissando illusion * Illusory continuity of tones * Illusory discontinuity * Hearing a

missing fundamental The pitch being perceived with the first harmonic being absent in the waveform is called the missing fundamental phenomenon. It is established in psychoacoustics that the auditory system, with its natural tendency to distinguish a tone from anoth ...

frequency, given other parts of the harmonic series *Various psychoacoustic tricks of

lossy audio compression In information theory, data compression, source coding, or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless. Lossless compression ...

McGurk effect The McGurk effect is a perceptual phenomenon that demonstrates an interaction between hearing and vision in speech perception. The illusion occurs when the auditory component of one sound is paired with the visual component of another sound, lea ...

Octave illusion The octave illusion is an auditory illusion discovered by Diana Deutsch in 1973. It is produced when two tones that are an octave apart are repeatedly played in alternation ("high-low-high-low") through stereo headphones. The same sequence is pla ...

/Deutsch's high–low illusion * Auditory

pareidolia Pareidolia (; ) is the tendency for perception to impose a meaningful interpretation on a nebulous stimulus (physiology), stimulus, usually visual, so that one detects an object, pattern, or meaning where there is none. Pareidolia is a specific bu ...

: hearing indistinct voices in random noise. * The Shepard–Risset tone or scale, and the Deutsch tritone paradox * Speech-to-song illusion * Yanny or Laurel

References

External links

Diana Deutsch's Web Page
{{Music cognition Music psychology Psychoacoustics

Causes

In music

Examples

See also

References

External links