Cross-Species Dyadic Synchrony as a Mechanistic Framework for Human–Animal Interaction: A Conceptual Review

Cross-Species Dyadic Synchrony: A Conceptual Review This conceptual review synthesizes emerging evidence of physiological and behavioral synchrony in human-animal dyads, proposing cross-species dyadic synchrony as a parsimonious mechanistic framework for human-animal interaction (HAI) research. Abstract Human–animal interactions (HAI) exhibit co‑occurring alignment across physiological and behavioral layers. This review synthesizes evidence from dog–human and horse–human dyads, focusing on autonomic entrainment (heart rate variability, HRV) and behavioral coordination (locomotor and postural micro‑adjustments). Autonomic entrainment co‑occurs with, and potentially informs, behavioral alignment, highlighting reciprocal and context‑sensitive patterns. Divergences between physiological and behavioral mechanisms underscore multi‑level regulatory complexity. Empirical updates, including Keeling et al. (2021), Proops et al. (2018), and Marcelli et al. (2023), strengthen behavioral and physiological silos while maintaining conceptual scaffolding. Implications for measurement integration, cross‑species comparisons, and future causal modeling are discussed. Keywords: human–animal interaction, dyadic synchrony, autonomic entrainment, behavioral coordination, heart rate variability Key Contributions:- Synthesizes dog-human and horse-human studies across autonomic entrainment (HRV) and behavioral coordination (locomotor/postural alignment)- Outlines provisional multi-level regulatory model (autonomic ↔ behavioral bidirectional interaction)- Addresses HAI field critiques regarding anecdotal mechanisms and vague relational constructs- Provides methodological recommendations including time-series analysis, pre-registration, and multi-modal measurement **Target Audiences:** Psychophysiology, animal behavior, equine-facilitated learning, animal-assisted interventions Preprint available via: | SSRNAuthor: Charles J. Wolf, Independent Researcher, CopenhagenLicense: CC-BY 4.0