Electroencephalogram γ-band activity during the perception of music key levels

An interdisciplinary research field, music perception involves various disciplines, such as psychology, neuroscience, and even physics. Research on music perception offers us a window into the mechanism of the brain. In music perception, the same distance of key shift in different directions tends to be perceived as different degrees of change. It, however, still remains unclear whether directional asymmetry is specific to key shift perception or a general phenomenon of key perception. Using both behavioral and electroencephalogram methods, this study examined Chinese nonmusicians' subjective ratings and electroencephalogram γ-band activity related to a piece of music performed at three different key levels and presented in three separate performances, none of which contained a key shift. This study showed that directional asymmetry is a general phenomenon of key level perception rather than specific to key shift perception. Furthermore, a counterclockwisely modulated key is related to stronger γ-band spectral power than a clockwisely modulated key.