Grouping Criteria.

Perfect synchronization, although essential in ensembles, has not been objectively evaluated. Further, the closely associated backbeat feel has not been adequately explained in the literature. This study introduces the groove hypothesis as a novel strategy for achieving perfect synchronization in musical ensembles, particularly in tasks involving backbeat feel. In ensemble playing, musicians must begin their movements before hearing the sounds of others to achieve synchronization. Conversely, in professional music settings, it is believed that target times are shared with an error of ±5ms based on experience, and this is considered perfect synchronization. Furthermore, while the word “groove” is used in various ways, here, it introduces the perspective of those who play groove. By examining the performance of participants using electronic drums with a 65-ms response delay, I identified two distinct synchronization strategies, shedding new light on how musicians and dancers manage rhythmic coordination. Based on the experimental results, the participants (ten university students and four dancers) were divided into Group A, which included six participants who could synchronize, and Group B, which included eight participants whose synchronization was delayed. Their p-values indicated that Group A used different strategies for the two plays. While the metrical swing theory explains why we can match a rhythm, I propose the groove hypothesis as a synchronization strategy for musicians: achieving perfect synchronization facilitated by imagining walking or running. The hypothesis suggests that we are aware of the motion of the center of gravity and that this awareness can be linguistically represented as a quiet inner “singing” in the brain. This idea is a new approach to music and dance performances and is also a proposal for cognitive science that suggests the possibility of linguistic imagery being involved in the perception of musical rhythms and synchronized movement of the body.

尽管完美同步在音乐合奏中至关重要，但目前尚未对其进行客观评估。与之密切相关的强反拍（backbeat）感知尚未在现有文献中得到充分阐释。本研究提出律动假说（groove hypothesis），将其作为实现音乐合奏完美同步的全新策略，尤其适用于涉及强反拍感知的任务场景。在合奏演奏中，乐手需在听到其他演奏者的声响前启动自身动作，方能实现同步。反之，在专业音乐场景中，从业者基于经验认为，演奏者间的目标时间共享误差可控制在±5毫秒以内，这一标准即被视为完美同步。此外，尽管"律动（groove）"一词的用法多样，但本研究中该术语特指律动演奏者的视角。本研究通过测试参与者在响应延迟65毫秒的电子鼓设备上的演奏表现，识别出两种截然不同的同步策略，为揭示乐手与舞者如何实现节奏协调提供了新视角。基于实验结果，本次受试对象（10名大学生与4名舞者）被分为两组：A组包含6名可实现同步的参与者，B组则包含8名同步存在延迟的参与者。两组的p值分析结果显示，A组在两种演奏任务中采用了不同的策略。尽管节拍摇摆理论（metrical swing theory）能够解释人类为何可匹配节奏，但本研究提出律动假说作为面向乐手的同步策略：通过想象行走或奔跑的动作，辅助实现完美同步。该假说指出，人类可感知自身重心的运动，且这种感知可通过大脑中静默的内在"哼唱"以语言意象的形式呈现。这一观点为音乐与舞蹈表演研究提供了全新思路，同时也为认知科学提出了新假说：语言意象或参与了音乐节奏感知与身体同步运动的过程。