Effects of static and dynamic canine-assisted intervention in young adults: sex differences in hormonal, EEG, HRV, and emotional responses

As mental health disorders like depression and anxiety rise, animal-assisted intervention (AAI) has emerged as a promising complementary approach, recognized for its psychological benefits. However, the underlying physiological mechanisms remain largely unexplored. The present study aims to investigate the impact of animal-assisted intervention on physiological, psychological changes and self-reported measurements. Thirteen young adults participated in three activities: meditation, static interaction with a dog, and dynamic interaction with a dog. Salivary hormone levels were measured by ELISA. Brain activity was recorded using electroencephalography (EEG). Cardiac activity was recorded using electrocardiography (ECG) for heart rate variability (HRV) analysis. Participants' emotional states were assessed using the semantic differential method (SDM). Results revealed sex-specific physiological and neurophysiological responses to AAI.​ In females, evidence for changes in oxytocin and cortisol was not consistent after multiplicity adjustment, and the point estimate for cortisol following dynamic activity suggested a decrease, although uncertainty remained. The EEG analyses indicated activity-related differences primarily in relative alpha power across multiple electrodes with some sex effects, whereas low-beta and high-beta effects were minimal after correction. Furthermore, SDM scores demonstrated emotional improvement following static and dynamic activities. These findings suggest that physiological and psychological responses after AAI are dependent on both sex and activity type.