The Mind on Music

For some reason that no one really understands, there is a psychological effect upon human listeners in regards to the musical scale. The tonic pitch, or tonal center is not only the mathematical center of the scale, but is the psychological center as well. Human perception of the tonic pitch in relation to the other notes of the scale gives each note of the scale, including the tonic pitch, a distinct "personality" or identity. If we were to label each note of the major scale with a number, with the tonic pitch being 1, then the ascending major scale would be 1, 2, 3, 4, 5, 6, 7, 1. The last 1 is an octave above the first, and could also be called 8; an octave above 2 could also be called 9, etc. When individual notes of the scale are played in certain melodic sequences, such as 1, 3, 2, 4, 3, 5, 4, 6, 5, 7, 6, 8, 7, 9... the human ear anticipates the next note to be 8 or 1, the tonic pitch. In the major scale, 2, 5 and 7 are notes that the ear usually expects to be followed by 1, if they are preceded by notes in a certain sequence. The psychological pull is strongest toward the tonic pitch, but this phenomena also exists in other parts of the scale as well. Notes that make the ear expect a certain note to follow them are called tendency tones. This psychological effect extends into harmony, which is the playing of several notes together as chords, and into chord progression, or the sequence of the chords played. This tension and release effect is extremely important in the perception of music.