Pitch is a perceptual property of sounds that allows their ordering on a frequency-related scale, or more commonly, pitch is the quality that makes it possible to judge sounds as 'higher' and 'lower' in the sense associated with musical melodies. Pitch can be determined only in sounds that have a frequency that is clear and stable enough to distinguish from noise."

Source Wikipedia

Musicians can readily spot a difference of just 1Hz in mid-range musical tones, and accurate pitch perception is thought to be crucial for speech perception - as well as musical appreciation.

The neural mechanisms which allow humans to determine pitch so accurately are as yet undiscovered.

What is known is that the sensory hairs in the cochlea respond to specific frequencies by induced vibration.

In the mid-range region, around the musical note 'A' (440Hz) the most sensitive discrimination tends to have an accuracy of about 1Hz. In the extreme upper and lower frequencies, the accuracy is much less.

Various theories have been proposed and tested ( see Wikipedia) but none gives a complete explanation for all observed capacities.

Computational modelling has provided new insights into the biological mechanisms that may underlie pitch perception, and modern brain imaging techniques have suggested possible cortical locations for pitch mechanisms. Nevertheless, a complete model describing all aspects of pitch perception is still lacking.

How the brain estimates the pitch of a complex sound remains unsolved. Complex sounds are composed of more than one tone. When two tones occur together, a third lower pitched tone is often heard. This is referred to as the “missing fundamental illusion” because the perceived pitch is a frequency (fundamental) for which there is no actual source vibration. This phenomenon exemplifies a larger variety of problems related to how pitch is extracted from complex tones, music and speech, and thus has been extensively used to test theories of pitch perception."

Source : Chaos 13, 1226–1230

Absolute pitch (widely referred to as perfect pitch) is an unexplained auditory phenomenon characterized by the ability of a person to identify or re-create a given musical note without the benefit of a technical reference tone. Early studies found that only around 1 in 10,000 people can do this. More recent studies, however, are showing that the skill of reproducing (or recognising) a piece of music at the correct pitch (though without the ability to actually name the note or key) is far more common that previously thought - perhaps in the region of 20-40% of the population.

See: How well do we understand absolute pitch? Acoust. Sci. & Tech. 25, 6 (2004)

Note: Several species of birds have calls that are accurately pitched to certain musical notes. And have remained so even after many generations (e.g. Chickadees). The implication being that the birds, like humans, must somehow have built-in absolute pitch discrimination.

Further info :Wikipedia

Also see : Rhythm perceptionplugin-autotooltip__plain plugin-autotooltip_bigRhythm perception

Humans (and some other animals*) have an innate sense of 'rhythm', i.e. the ability to detect and react with 'beats' in musical compositions. Professional drummers and percussionists can 'beat time' with accuracies of just a few milliseconds per beat (ref. and Musical appreciationplugin-autotooltip__plain plugin-autotooltip_bigMusical appreciation

Music psychologists are trying to understand the processes that support musical behaviours - including perception, comprehension, memory, attention, emotional effects, and performance.

"Music is more mysterious than language because its