Music perception requires the generation of internal representations, the music must be analysed in several dimensions, recognised, and acted upon. Music relies on the relation between elements, rather than on absolute values of elements. For example – a tune relies not on the pitches of its melody but on the arrangement of the intervals between the pitches.
Pitch (melodic) and time-based (temporal) relations have traditionally been treated separately. Dissociation between melodic and temporal processing has been seen in sight-reading and singing, and suggest that the two dimensions operate in separate neural systems.
Evidence suggests that listeners use scale structure in melodies for perception and memory. This evidence points to the existence of neural networks that are specialised for the processing of scales in melodies.
Pitch relations in chord sequences are governed by the harmonic and perceptual principals similar to that of the scale. Some chords are more related to one another, with one chord acting as a reference (the tonic). By the age of 5, the degree of harmonic appropriateness of chord progressions appears to be assimilated, based on passive exposure to western tonal tradition.
Two types of time relations are fundamental to the temporal organisation of music (rhythm). The segmentation of an ongoing sequence into temporal groups of events based on their durational values, and the extraction of an underlying temporal regularity or beat. Studies reveal that there is a dissociation between grouping (metrical organisation) and regularity (beat) and are processed separately.