Dogs showed lower parasympathetic activity during mutual gazing while owners did not

Table 5 Results of LMM of the change in each HRV parameter for 6 s before and 6 s after the moment dogs gazed at human participants

	meanRRI			SDNN			rMSSD
	β	t	p	β	t	p	β	t	p
Dog's HRV
Intercept		60.545	< 0.001		22.740	< .0001		14.246	< .0001
Dog's sex (female dog)	− 0.079	1.231	0.242	0.030	− 0.249	0.808	0.080	− 0.440	0.668
Owning period	0.015	0.872	0.393	*− 0.087*	*− 2.502*	*0.024*	− 0.098	− 1.897	0.075
Episodes (OW ep.)	*− 0.015*	*− 2.407*	*0.016*	*− 0.097*	*− 5.688*	< *0.001*	*− 0.105*	*− 4.815*	< *0.001*
Time	0.000	− 0.300	0.764	− 0.002	− 0.473	0.636	0.003	0.523	0.601
Episodes (OW ep.) * Time	− 0.001	− 0.663	0.508	0.005	1.254	0.210	0.001	0.278	0.781
Adjusted R²	0.622			0.586			0.658
Human HRV
Intercept		*97.017*	< *.0001*		*14.679*	< *.0001*		*10.641*	< *.0001*
Dog's sex (female dog)	0.041	− 1.085	0.298	0.091	− 0.673	0.513	0.170	− 0.961	0.354
Owning period	0.000	− 0.008	0.994	− 0.034	− 0.793	0.442	− 0.031	− 0.557	0.587
Human participant (owner)	− 0.009	− 1.950	0.052	− 0.404	*− 20.440*	< *.0001*	*− 0.413*	*− 21.800*	< *.0001*
Time	0.001	0.969	0.333	− 0.001	− 0.358	0.721	− 0.002	− 0.442	0.659
Human participant (owner) * Time	0.000	0.248	0.805	− 0.002	− 0.379	0.705	0.001	0.348	0.728
Adjusted R²	0.605			0.564			0.634

β indicates partial regression coefficient
Dog’s sex: female dog against male dog
Episodes: OW episodes (dogs with owners) against ST episodes (dogs with strangers)
Human participants: owner against stranger
Bold italicized numbers indicate that the results were statistically significant

ISSN: 1880-6562