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

Fig. 1. Timeline of data collection in minutes Note. The timeline presented illustrates the sequence and duration of activities involved in the data collection process, specifically in minutes

Fig. 2. Cross-wavelet power analysis of HRV synchronization: therapy horse and participant during a four-minute segment in an initial HAT session Note. The figure displays a cross-wavelet power analysis of HRV synchronization between the therapy horse and the participant during a four-minute segment in an initial HAT session. The color scale represents the effect size, with warmer colors (red and orange) indicating higher synchronization levels and cooler colors (blue and green) indicating lower synchronization levels. The arrows represent the phase relationship between the HRV signals of the horse and the participant, with the direction of the arrows showing the phase angle. The x-axis represents the time in seconds, while the y-axis represents the period in seconds (the duration of each cycle in the HRV signals, which is inversely related to frequency by the relationship Period = 1/Frequency)

Fig. 3. HF-HRV synchronization of therapy horses and riding therapists Note. This figure illustrates HF-HRV synchronization via cross-wavelet power values between therapy horses (TH1 - TH4) and riding therapists (RT1 - RT3). Violin plots show data distribution, with jittered points and black dots indicating mean values. Error bars represent 95% confidence intervals from bootstrapping. The high density of data points can be explained by obtaining one value per every 10 s for each session in our analysis. The black boxes mark the favorite therapy horse for each riding therapist, highlighting the cross-wavelet power value distributions specific to these preferred horses

Fig. 4. Impact of childhood trauma severity on mean cross-wavelet power between therapy horse and participant. Mean cross-wavelet power therapy horse and participant across intervals (10 s), stratified by Childhood Trauma Questionnaire (CTQ) total scores. Participants were grouped based on their CTQ total scores into the following categories: x ≤ 25 (green), 26 < x ≤ 40 (yellow-green), 41 < x ≤ 55 (yellow), 56 < x ≤ 70 (orange), 71 < x ≤ 85 (red-orange), and > 85 (red). Each point represents the mean value for the group in a given interval, and the lines connect the means across intervals. Error bars represent 95% confidence intervals calculated using bootstrap resampling. The color gradient from green to red visually represents increasing CTQ total scores, indicating higher levels of reported childhood trauma

Fig. 5. Impact of childhood trauma severity on mean cross-wavelet power between riding therapist and participant Note. Mean cross-wavelet power therapy horse and participant across intervals (10 s), stratified by Childhood Trauma Questionnaire (CTQ) total scores. Participants were grouped based on their CTQ total scores into the following categories: x ≤ 25 (green), 26 < x ≤ 40 (yellow-green), 41 < x ≤ 55 (yellow), 56 < x ≤ 70 (orange), 71 < x ≤ 85 (red-orange), and > 85 (red). Each point represents the mean value for the group in a given interval, and the lines connect the means across intervals. Error bars represent 95% confidence intervals calculated using bootstrap resampling. The color gradient from green to red visually represents increasing CTQ total scores, indicating higher levels of reported childhood trauma