ABSTRACT
The human ear is sensitive to acoustic waves in a wide range of frequencies, and can detect very small frequency variations, a resolution of less than 0.5% in the discernible threshold. On the other hand, the western music is based on scales that have frequency transitions of 20 times that resolution. In neuropsychological terms, the existence os scales can be justified by the facility that it offers the brain to process, identify, and store a melody that is formed by a temporal sequence of discrete pitch values, which are related in some way, as in a harmonic series. Tonality is related to music centered around a home key, based on a major or minor scale. A major key is a type of music based on a major scale, which is traditionally considered happy sounding, while a minor key is a kind of music based on a minor scale, which is traditionally considered sad sounding.
