Emotional transfer between humans and animals

Emotions can be triggered not only by external stimuli such as images or sounds, but also by looking at another individual and feeling sensations in your own body. This is known as emotional contagion, which is closely linked to the ability to empathize. However, this empathizing with another individual involves yet another component, namely the ability to distinguish whether the emotions felt originate in oneself or in the other person. Effective social functioning requires the ability to distinguish one's own emotional state from that of others, only then can we speak of the ability to empathize. According to an experimental study, adults are more able than children to recognize emotions as their own or others'[1].

Although emotions are automatisms of an individual, they are connected to the social world. Emotions also represent an integrative function between the two antagonisms of the conscious mind and automatism. It is assumed that the original function of emotions concerns the communication system, which is shaped at a young age through mimicry with the environment and emotional contagion. This emotional system is completely dependent on the environment. It can be seen as a tool to coordinate with the environment. Mental and motor adaptive responses would thus provide the necessary plasticity for the emergence of consciousness[2]

People can experience the emotional states of others and use these embodied reactions to understand and predict behavior in complex social interactions. The observer's body plays a special role here, as it is needed for these complex social tasks such as imitation or perspective taking[3]. 

Emotional contagion and empathizing with a counterpart occurs in many mammals and also in birds. One possible benefit is the passing on of information, which optimizes protection against predators. It also facilitates group living. Emotional contagion has already been observed in a large number of species. It must be taken into account that imitation of a certain behavior does not necessarily imply the contagion of a corresponding emotion. An emotion is defined both by its level of arousal and by its positive or negative valence (evaluation). Measuring fluctuations in heart rate is therefore not sufficiently informative for a scientist. At the same time, changes in behavior must also be taken into account. In humans, the cognitive components can still be taken into account, the subjective feeling, the measurement of which in non-human animals is currently considered difficult to impossible. Accordingly, the majority of animal research has focused on objectively measurable components to determine the presence and nature of an emotional state. For example, locomotor activity is one of the most direct, non-invasive behavioral measures of emotional expression, meaning that whether animals approach or avoid a stimulus can inform us about the rewarding or non-rewarding qualities of that stimulus, and thus assume its positive or negative characteristics. However, animals tend to show variation in the way they respond to environmental manipulations, which is attributed to their personalities. For example, individuals of a species differ in their vigilance towards threatening stimuli, their motivation to explore new contexts or their activity level in general. Thus, if we measure only one (behavioral) component instead of a larger set, we limit and potentially confound our interpretations of the respective emotional state. For this reason, it is valuable to broaden efforts to examine a collection of multiple components ranging from behaviors such as redirected behavior, visual orientation, activity level or posture, to vocalizations and, when possible, measures of physiological parameters.[4] 

However, the transfer of emotions also occurs across species. As it occurs particularly in members of the social group or in individuals with strong social bonds, it stands to reason that this is also possible between animals and humans in close relationships. The animal most studied in this respect is the dog (Canis familiaris), one of the oldest domesticated species. Due to their coexistence with humans for more than 30,000 years, they are closely interwoven into human society as bonding partners. They have acquired human-like communication skills and, probably as a result of the domestication process, the ability to read human emotions. In one study, the emotional responses of dogs and humans were evaluated using heart rate variability under a psychological stress condition of the owner. The correlation coefficients of heart rate intervals between dogs and owners were positively correlated with the duration of dog ownership. The sex of the dogs also influenced this. Female animals showed stronger values. These results suggest that emotional contagion from owner to dog may occur especially in females and that the amount of time they share the same environment is the key factor in the effectiveness of emotional contagion. The effect of emotional contagion between dog owners and their companions seems to be more pronounced the longer a dog lives with an owner[5].

A study on the effects of emotional contagion between dogs and humans in a therapeutic setting revealed extremely remarkable findings. Study participants were people with severe post-traumatic stress disorder (PTSD) whose symptoms included re-experiencing traumatic events, avoidance, hyperarousal and cognitive deficits reflected in both emotional and cognitive dysregulation. In recent years, non-pharmacological approaches, and animal-assisted therapy in particular, have been shown to be helpful for a range of disorders including attention-deficit/hyperactivity disorder, autism spectrum disorder and PTSD. In this context, the current study looked at the reciprocal effects of the interaction between animals and humans, an aspect that is currently still the focus of little scientific attention.

In the study, human participants suffering from post-traumatic symptoms underwent 12 months of training with dogs. This involved classic exercises from dog training. The humans therefore focused intensively on teaching dogs something. As a side effect of this simple but concentration-requiring task together with an animal, it was hoped that the psychological symptoms of the people would improve.

7 males and 5 females of the Malinois and German Shepherd breeds aged 1.4 ± 0.5 years took part. They had no previous dog training experience.

In each case, 2-3 participants trained a specific dog. The initial training of the dogs was carried out by professional dog trainers. After learning the basics of handling dogs, the participants were gradually given more responsibility over the course of the year. They were initially responsible for care, later they were allowed to go for walks and then behavior training 3-5 times a week for 3 hours at a time. Each interaction with a dog on a given working day was carried out by a single team member, while other team members and an instructor observed them. Participants learned the principles of dog training, classical and operant conditioning, the effectiveness of various reinforcement schedules, and ethical guidelines for treating and training dogs. Basic discipline exercises with the dogs included responding to verbal commands using a positive reinforcement stimulus, such as food or a training ball, depending on the dogs' individual preferences. Participants also learned to familiarize themselves with different dog training methods, such as the use of a clicker, different types of reinforcement and leadership styles. Negative feedback was allowed to be given verbally (“bad boy”) when necessary and only with the consent of the trainers. The use of non-verbal punishments was prohibited.

The control group also received non-pharmacological interventions, but without animal training. The methods included Eye Movement Desensitization and Reprocessing (EMDR), trauma-focused cognitive behavioural therapy and other methods that have been shown to reduce PTSD symptoms.

After one year, there were significant improvements in PTSD symptoms with a simultaneous reduction in the severity of depressive symptoms in the dog training group. In the control group, on the other hand, there was only an insignificant improvement. Improved emotion and attention regulation was also observed in the dog training group. There were therefore significant positive effects of dog training.

What sets the study apart from others, however, is that following the observation of the positive effects in the subjects of the dog training program, the underlying mechanism of these effects was investigated. The interaction with the dogs came to the fore. In this context, the effects of the training on the dogs were also considered, with remarkable findings. The emotional and attentional performance of the dogs was measured using computer-based objective methods, which assessed various behaviors of the dogs such as fear and selective attention. There was a noticeable negative effect on the dogs' performance. Their anxiety-like behavior increased and their ability to selectively pay attention decreased.

Thus, one year of dog training with the PTSD study participants had positive effects on the humans with negative effects on the dogs. The scientists postulated that the negative effect on the dogs was due to the interaction between dog and owner. However, they questioned whether it was the nature of the interaction or the training method used in the program[6].

If we now assume that emotional contagion has far-reaching significance for our coexistence, whether within a species or across species, it is necessary to take up the aspect of empathy again. This is seen as a fundamental force of morality. Empathy is a phenomenon that has profound effects on various areas of social interaction, be it between humans or between humans and animals. It is important to point out that empathy, which arises on the basis of emotional contagion, is not primarily genetically predisposed. It can be both learned and unlearned. Its roots are not as firm as we like to believe. The adaptive mechanism that distinguishes empathy from pity, envy, gloating and sadism is a product of learning. Research suggests that the mechanism of empathy, emotional contagion, is constructed in the course of development through social interaction. Learned matching implies that empathy is both mobile and fragile. It can be strengthened and redirected by new experiences, and broken by social change.[7]