A body-brain-behavioral cross-frequency architecture links biological and behavioral periodicities

Spontaneous behaviors, e.g., walking and speaking, are thought to rely on an internal sense of time that provides a scaffold for precise temporal coordination. Yet the endogenous rates of many behavioral processes often diverge from the arbitrarily defined unit of objective time (Chronos), raising a fundamental question: what temporal reference frame coordinates behavior? Recent theoretical work (Buzsaki, 2026) proposed the rich repertoire of subjective time (Kairos) to fluctuate in function of a dynamic cross-frequency architecture linking body-brain periodicities along a lognormal linear progression in the frequency domain. Withing this framework, an emergent sense of time may regulate the rate of semi-periodic behaviors. Using high temporal resolution multimodal recordings, we show that endogenous body-brain periodicities, including pupil fluctuations, saccadic eye movements, respiration, cardiac activity and neural oscillations, as well as spontaneous behaviors such as tapping, walking, and speaking, are organized as an arithmetic progression in a natural logarithmic frequency space. This observation suggests that a unified scaling law may coordinate complex, multi-scale interactions across biological and behavioral timescales. We propose that such organization may provide an emergent temporal reference frame that scaffolds perception and action.