HONOLULU, Dec. 2, 2025 — Some music is for grooving: It evokes spontaneous dancing, like head bopping, jumping, or arm swinging. Other music is for swaying, or for crying, or for slow dancing. Music makes people move, but whether musicians intentionally induce specific movements with their compositions, such as vertical bouncing or horizontal swaying, or what musical features would contribute to these distinctions, is more complex.
Shimpei Ikegami, an associate professor at Showa Women's University, sought to understand how musicians express intended bodily movement directions using specific acoustic features.
"It's almost magical how something we hear with our ears can influence our entire body. In Japan, we even have terms to describe distinct rhythmic feelings to music," Ikegami said.
Ikegami will present his musical results Tuesday, Dec. 2, at 2:55 p.m. HST as part of the Sixth Joint Meeting of the Acoustical Society of America and Acoustical Society of Japan, running Dec. 1-5 in Honolulu, Hawaii.
Four professional pop musicians composed short musical excerpts intended to elicit either "tate-nori" (vertical, up-and-down movement), "yoko-nori" (horizontal, side-to-side movement), or neither movement type.
Ikegami quantified the acoustic characteristics of the excerpts, measuring features such as loudness, beat clarity, rhythm complexity, and timbre. By comparing the prominence of features across intended-movement conditions, he found that vertical "bop" music was characterized by a clearer beat and percussive sounds, fueling listeners with the rush of high-energy workout songs. In contrast, horizontal "sway" excerpts were smoother and included less percussive sounds, creating a mellow and atmospheric musical impression. In a listener-rating experiment, participants heard each excerpt and rated the extent to which it made them feel like moving vertically and horizontally. Ikegami found that the listeners' directional dancing inclinations matched the musicians' intended expressions.
Ikegami's findings suggest that the way musicians express certain qualities of danceability is specific and quantifiable. He aims to further explore commonalities and differences between musical profiles that induce vertical versus horizontal bodily movement.
"In the immediate future, I am investigating the psychological impressions — how the music is perceived by listeners. I am also deeply interested in cultural differences in these phenomena," said Ikegami. "I believe that advancing my understanding of how music influences our body movements could be beneficial in fields such as health care, rehabilitation, and education."
