Tomoyo Shiramatsu Graduate School of Information Science and Technology, The University of Tokyo

In this study, we focus on rhythm in music as an acoustic Shitsukan. Why does the rhythms in some music induce physical movement in us, but not always in other animal species? In order to answer this question, we will test two hypotheses, i.e., the originated in body and in brain hypothesis, by analyzing brain activity in the auditory cortex and body movement of rats. In behavioral and physiological experiments, we investigate which rhythms induce the most robust body movement and how they induce neural activity in the auditory cortex, and explore the relationship between them. If the originated-in-body hypothesis is correct (i.e., the music in human culture also appeals to rats’ brains), we try to emphasize their rhythmic movements by changing the resonance frequency of the body structure by changing the posture of rats or placing weights on their heads.
If the originated-in-brain hypothesis is correct, we will identify music-like stimuli for rats that are most appealing to the rat brain based on the neural activity of the auditory cortex. In addition to the sensory system, this study will demonstrate the importance of values in the senses, emotions, physical reactions, and behaviors in understanding the deep Shitsukan.