It is widely acknowledged that dogs and humans share a strong emotional bond and often mirror each other's behavior. For about two decades now we now that inter species emotional contagion can result in acute short term stress synchronization. Emotional contagion refers to the process by which emotions can spread from one individual to another, resulting in a shared emotional experience. This fascinating phenomenon has been observed not only in humans but also in dogs, suggesting a powerful emotional connection between these two species.

Emotional contagion involves the unconscious mimicry of emotional expressions, vocalizations, and behaviors between individuals. When one individual experiences an emotion, such as happiness or fear, it can elicit a similar emotional response in others, leading to a shared emotional state. This process can occur within and across species, highlighting the empathic nature of emotional contagion. Dogs are sensitive to human emotional cues and can display emotional contagion. Dogs are also known to perceive and interpret human facial expressions, tone of voice, and body language, allowing them to mirror emotions expressed by their human companions. For example, if a person exhibits fear, aggression, anxiety or sadness, it can trigger similar emotional responses in dogs, leading to increased stress levels in both the dog and human. That mirroring of stress we call stress contagion and was believed to be short term mirroring. A phenomenon observed in Law enforcement and police K9’s. The elevated stress from the handler results in elevated stress of the K9. The same observations are made in the sport dog world, where handlers gets stress in trial and competitions resulting in lesser performance of the dog due the short term stress mirroring.

Recent scientific studies have focused on exploring the connection between dogs and their owners, particularly concerning stress levels. Research suggests that long-term stress is not only experienced by humans but can also extend to their canine companions, resulting in a fascinating long term synchronization of stress levels between the two species. We learned that dogs rely on verbal and non-verbal cues to gauge their owner's emotional state, and we know that dogs can accurately discern subtle signs of stress such as elevated heart rate, changes in body language, and even the release of stress-related hormones like cortisol.

Synchronized Stress Responses:

In a groundbreaking study by Dr. Ann-Sofie Sundman, her and a team researchers examined the cortisol levels of both dogs and their owners over an extended period. They studied and explored the intriguing relationship between human hair cortisol concentration (HCC) and dog hair cortisol concentrations (DHCC). Cortisol is a hormone produced in response to stress, and elevated cortisol levels are indicative of chronic stress. The study revealed a remarkable synchronization of cortisol patterns in dogs and their owners. When owners experienced higher stress levels, their dogs displayed corresponding increases in cortisol. Conversely, when owners were less stressed, the cortisol levels in their dogs also decreased. Her and other studies have demonstrated a unique connection between human and dog cortisol levels, suggesting that dogs are more sensitive to their owners' stress levels then previously believed. Just as dogs can mirror the stress levels of their owners through behavioral and physiological changes, they may also reflect similar levels of cortisol in their hair. It is believed that the presence of a chronically stressed human can contribute to elevated cortisol levels in their canine companions.

Factors Influencing Synchronization:

Several factors play a role in the synchronization of stress levels between dogs and their owners. Firstly, the emotional bond shared between the two is crucial. Dogs are highly attuned to their owner's emotions, forming a strong psychological connection. Additionally, dogs and humans often share the same living environment, making them susceptible to common stressors such as work-related pressures, relationship issues, or financial burdens. These shared stressors further contribute to the synchronization of stress levels.

1. Breed Variations and Hair Cortisol Concentrations:

Breed-specific differences have been observed in many physiological and psychological aspects of dogs, including their response to stress. It is plausible that these breed differences may also manifest in variations in DHCC. Certain breeds are more predisposed to exhibiting different cortisol levels in their hair. Factors such as genetics, breeding history, and temperament could potentially contribute to breed-specific variations in DHCC.

2. Sex Differences:

Gender is another factor that may influence DHCC. Hormonal differences between male and female dogs could play a role in cortisol production and regulation. Studies have shown slight variations in DHCC between male and female dogs, with some suggesting higher cortisol levels in females. However, more research is needed to understand the specific mechanisms behind these sex differences and their impact on DHCC.

3. Effects of Lifestyle:

Lifestyle factors, including the environment, routines, and socialization of dogs, can have a significant impact on their stress levels and subsequent cortisol concentrations. Dogs living in consistently stressful environments or experiencing disruptions in their daily routines may exhibit higher DHCC. Conversely, dogs with enriched and supportive lifestyles, with ample opportunities for exercise, play, and social interaction, may demonstrate lower cortisol levels in their hair. Diet, healthcare, and exposure to other animals or challenging situations could also influence DHCC.

Implications for the Canine - Human Bond:

Understanding the effects of human HCC, breed, sex, and lifestyle on DHCC can have practical implications for both dogs and their owners. Elevated cortisol levels in dog hair may indicate persistent stress and potential health risks. Recognizing this correlation allows owners to pay closer attention to their dogs' well-being and seek appropriate interventions to reduce stress levels for both the dog and themselves. Additionally, this knowledge further reinforces the importance of providing a supportive and stress-free environment for the overall welfare of dogs. The synchronization of long term stress levels between dogs and their owners yields important implications for both parties' mental and physical well-being. It highlights the reciprocal nature of the human-dog relationship, emphasizing how our emotions impact our furry companions and vice versa. Recognizing this synchronization can potentially allow owners to become more aware of their own stress levels by observing changes in their dogs. Moreover, it underlines the importance of creating a harmonious and stress-free environment for both humans and their four-legged friends.

This emerging field of research exploring the synchronization of stress levels between dogs and their owners has shed new light on the unique bond shared by these two species. The findings affirm the strong emotional connection between humans and their canine counterparts, revealing that long-term stress can be mutually experienced. As further studies continue to investigate this fascinating phenomenon, it is increasingly evident that the well-being of dogs and their owners, their success in training and learning together, is intricately interconnected. Blaming the dog for “disobedience’ should be reconsidered quite often. In many cases in failure in training, giving the dog the benefit of the doubt and start some self reflection is probable the smart choice. Always promoting a calm and stress-free environment for both you and your dog is essential in nurturing a healthy and harmonious and balanced relationship.