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Journal of neural transmission (Vienna, Austria : 1996)2025; doi: 10.1007/s00702-025-02947-7

The relationship of early life adversity and physiological synchrony within the therapeutic triad in horse-assisted therapy.

Abstract: In any therapeutic setting, the outcome depends in part on the therapeutic alliance, characterized by mutual understanding, empathy and trust among the participants. This also manifests through physiological synchronization (PS) processes involving breathing, heart and brain. This study examined the dynamics of heart rate variability (HRV) synchronization patterns during horse-assisted therapy. We explored the correlations between the therapist's horse preference, levels of early life adversity (ELA), and PS relationships within and across dyads of participants, therapists, and therapy horses. Our sample of 42 female participants engaged in standardized horse-assisted therapy sessions facilitated by three riding therapists and four therapy horses. PS was operationalized through cross-wavelet power analyses across the different dyads. The results showed, that stronger HRV synchronization between the therapist and horse was associated with stronger HRV synchronization between the horse and participant, as well as stronger HRV synchronization between the therapist and participant. We found a correlation between ELA and HRV synchronization between participants and therapists, with individuals experiencing higher levels of ELA showing lower synchronization. However, this effect of ELA was not observed for HRV synchronization between participants and horses. Furthermore, we found a negative correlation between the riding therapist's preference for a particular therapy horse and the HRV synchronization between the therapist and that horse. These findings contribute to a better understanding of the correlational dynamics in horse-human interactions and may have potential implications for optimizing therapeutic interventions in clinical settings.
© 2025. The Author(s).
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Publication Date: 2025-05-27 PubMed ID: 40423728PubMed Central: 5040734DOI: 10.1007/s00702-025-02947-7Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The article focuses on examining the patterns of heart rate variability (HRV) synchronization during horse-assisted therapy. The role of factors like therapist’s horse preference and levels of early life adversity (ELA) are considered in these dynamics. The findings suggest higher HRV synchronization between the therapist and horse also heightens the same with the horse and participant as well as the therapist and participant, while higher levels of ELA can bring down synchronization between participants and therapists but not between participants and horses.

Understanding the Research

  • The research attempts to understand the dynamics of physiological synchronization (PS), particularly heart rate variability (HRV) synchronization, in horse-assisted psychotherapy. It achieves this by examining its relationship with factors such as the levels of early life adversity (ELA) experienced by the participants and the horse preference of the therapists.
  • Horse-assisted therapy involves interaction between the participant, therapist, and therapy horse. Thus, understanding the synchronization between this triad can help optimize therapeutic interventions.
  • HRV is a measure of the change in time intervals between successive heartbeats and is an important indicator of emotional, psychological, and physiological states of an individual.
  • Physiological synchronization is a phenomenon where participants in a shared experience exhibit similar physiological responses, such as heart rate and breathing patterns. In the context of therapy, a higher degree of synchronization is often indicative of a stronger therapeutic alliance and better therapy outcomes.

Research Methodology

  • A sample of 42 female participants, with three riding therapists and four therapy horses, was engaged in standardized horse-assisted therapy sessions.
  • PS was operationalized through a method called cross-wavelet power analysis – a technique used to study the correlation in the frequency domain between two time-series.

Key Findings

  • The research found that if therapists and horses had a stronger synchronization, so did the horse and participant as well as the therapist and participant, which indicates the effect of establishing clear rapport and understanding between the therapist and horse.
  • The level of ELA among participants influenced the degree of synchrony with the therapist, such that individuals with higher levels of ELA demonstrated lower HRV synchronization.
  • Interestingly, a higher level of ELA did not affect the HRV synchronization between the participants and the horses, underlying the unique therapeutic potential of equine-assisted therapies in supporting individuals with higher ELA.
  • The study also revealed a negative correlation between a riding therapist’s preference for a particular therapy horse and the HRV synchronization between the therapist and that horse. This surprising finding might need further investigation and unpacking.

Implications of the Findings

  • The insights from this study contribute to our understanding of the dynamics in horse-human interactions during therapy sessions.
  • The findings are likely to have potential implications for clinical settings, providing valuable information that can help to enhance the effectiveness of horse-assisted therapy, particularly by focusing on the significance of human-animal psychophysiological connection.

Cite This Article

APA
Wienhold S, Bär L, Ringleb Z, Zirpel V, Gomolla A, Denk BF, Volkmer N, Gaertner RJ, Klink ESC, Pruessner JC. (2025). The relationship of early life adversity and physiological synchrony within the therapeutic triad in horse-assisted therapy. J Neural Transm (Vienna). https://doi.org/10.1007/s00702-025-02947-7

Publication

Journal of neural transmission (Vienna, Austria : 1996)
ISSN: 1435-1463
NlmUniqueID: 9702341
Country: Austria
Language: English

Researcher Affiliations

Wienhold, Stella
  • Neuropsychology, Department of Psychology, University of Konstanz, Konstanz, Germany. stella.wienhold@uni-konstanz.de.
  • GREAT - German Research Center for Equine Assisted Therapy, Konstanz, Germany. stella.wienhold@uni-konstanz.de.
  • Centre for the Advanced Study of Collective Behavior, University of Konstanz, Konstanz, Germany. stella.wienhold@uni-konstanz.de.
Bär, Larissa
  • Neuropsychology, Department of Psychology, University of Konstanz, Konstanz, Germany.
  • GREAT - German Research Center for Equine Assisted Therapy, Konstanz, Germany.
Ringleb, Zoe
  • Neuropsychology, Department of Psychology, University of Konstanz, Konstanz, Germany.
  • GREAT - German Research Center for Equine Assisted Therapy, Konstanz, Germany.
  • Centre for the Advanced Study of Collective Behavior, University of Konstanz, Konstanz, Germany.
Zirpel, Victoria
  • Neuropsychology, Department of Psychology, University of Konstanz, Konstanz, Germany.
  • GREAT - German Research Center for Equine Assisted Therapy, Konstanz, Germany.
Gomolla, Annette
  • GREAT - German Research Center for Equine Assisted Therapy, Konstanz, Germany.
Denk, Bernadette F
  • Neuropsychology, Department of Psychology, University of Konstanz, Konstanz, Germany.
  • Centre for the Advanced Study of Collective Behavior, University of Konstanz, Konstanz, Germany.
Volkmer, Nina
  • Neuropsychology, Department of Psychology, University of Konstanz, Konstanz, Germany.
  • Centre for the Advanced Study of Collective Behavior, University of Konstanz, Konstanz, Germany.
Gaertner, Raphaela J
  • Neuropsychology, Department of Psychology, University of Konstanz, Konstanz, Germany.
Klink, Elea S C
  • Neuropsychology, Department of Psychology, University of Konstanz, Konstanz, Germany.
Pruessner, Jens C
  • Neuropsychology, Department of Psychology, University of Konstanz, Konstanz, Germany.
  • Centre for the Advanced Study of Collective Behavior, University of Konstanz, Konstanz, Germany.

Conflict of Interest Statement

Declarations. Ethics approval and consent to participate: All procedures performed in our study followed regulations set forth by the Declaration of Helsinki and were approved by the institutional review board of the University of Konstanz (IRB statement 12/2017). Our research did not result in stigmatization, incrimination, discrimination or personal risk to participants. Conflict of interest: The authors declare no conflict of interest. All contributors of this study who have fulfilled the criteria for authorship required by springer nature journals have been included as authors.

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Citations

This article has been cited 1 times.
  1. Denk BF, Pruessner JC, Farah S, Barth C, Putra PU, Lenggenhager B, Grütter J. Cardiac synchrony, peer relationships, and affective experiences in children during group interactions. Sci Rep 2026 Feb 25;16(1).
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