The glissando illusion is an

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 p ...

, created when a sound with a fixed pitch, such as a synthesized

oboe The oboe ( ) is a type of double reed woodwind instrument. Oboes are usually made of wood, but may also be made of synthetic materials, such as plastic, resin, or hybrid composites. The most common oboe plays in the treble or soprano range. A ...

tone, is played together with a

sine wave A sine wave, sinusoidal wave, or just sinusoid is a curve, mathematical curve defined in terms of the ''sine'' trigonometric function, of which it is the graph of a function, graph. It is a type of continuous wave and also a Smoothness, smooth p ...

gliding up and down in pitch, and they are both switched back and forth between

stereo Stereophonic sound, or more commonly stereo, is a method of sound reproduction that recreates a multi-directional, 3-dimensional audible perspective. This is usually achieved by using two independent audio channels through a configuration ...

loudspeakers. The effect is that the oboe is heard as switching between loudspeakers while the sine wave is heard as joined together seamlessly, and as moving around in space in accordance with its pitch motion. Right-handers often hear the

glissando In music, a glissando (; plural: ''glissandi'', abbreviated ''gliss.'') is a glide from one pitch to another (). It is an Italianized musical term derived from the French ''glisser'', "to glide". In some contexts, it is distinguished from the co ...

as traveling from left to right as its pitch glides from low to high, and then back from right to left as its pitch glides from high to low. The effect was first reported and demonstrated by

Diana Deutsch Diana Deutsch (born 15 February 1938) is a British-American psychologist from London, England. She's a Professor of Psychology at the University of California, San Diego, and is a prominent researcher on the psychology of music. Deutsch is p ...

in ''Musical Illusions and Paradoxes'', 1995.

References

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WeblinkPDF Document

External links

Deutsch, D. Hamaoui, K. Henthorn, T. The Glissando Illusion: A Spatial Illusory Contour in Hearing. Journal of the Acoustical Society of America, 2005, 117, p. 2476.

Glissando illusion example.

References

External links

See also