Scientific pitch notation creates a linear pitch space in which an octave spans 12 semitones, where each semitone is the distance between adjacent keys of the piano keyboard. Distance in this space corresponds to musical pitch distance in an equal-tempered scale; 2 semitones being a whole step, 1 semitone being a half step. An equal-tempered semitone can also be subdivided further into 100 cents. Each cent is semitone or octave. This measure of pitch allows the expression of "microtones" not found on standard piano keyboards. The notation is sometimes used in the context of meantone temperament, and does not always assume equal temperament
Octave experience octave equivalency, and its biological basis apparently is an octave mapping of neurons in the auditory thalamus of the mammalian brain. Studies have also shown the perception of octave equivalence in rats , human infants , and musicians but not starlings , 4–9 year old children , or nonmusicians . Most musical scales are written so that they begin and end on notes that are an octave apart. For example, the C major scale is typically written (shown below), the initial and final C's being an octave apart. \override Score.TimeSignature #'stencil = ##f \relative c' { </score> Because of