Natural Minor Scale is More Natural to the Brain than Harmonic Minor Scale as Revealed by Magnetoencephalography

Minor mode is known to elicit stronger emotional responses than major mode in the brain. The present work focused on the minor scales and natural and harmonic minor scales were compared in automatic brain responses in an oddball paradigm. The standard stimulus was either the natural or harmonic minor scale, and a deviant stimulus lacked one scale tone of the corresponding complete minor scale. The brain responded to omission of every tone but omission of the tone B flat in the natural minor experiment elicited larger response than that of the other tones. In particular, the response was significantly larger than that to omission of B in the harmonic minor experiment. This result suggested that the brain felt the natural minor scale to be actually more natural than the harmonic minor scale.