We hug each other when we are happy or when our heart cries, sometimes just to say hello. Hugs play a role important in our lives and they are a powerful tool of non-verbal communication. This gesture, for anatomical reasons, is only possible for primates. Embracing is also experienced from birth onwards in mother–infant interactions and is thus accompanying human social interaction across the whole lifespan. Despite the importance of embraces for human social interactions, their underlying neurophysiology is unknown.
Strong feelings influence the way of embracing
Laterality or asymmetry in actions physics is known above all for what concerns the predominance in the use of one hand or foot: in most people the hand is the dominant feet are the right ones, and therefore the people use their right hand, for example, to grab a cup and right foot to kick a ball. A study published in 2022 by Packheiser et al., demonstrated in a well-powered sample of more than 2500 adults that humans show a significant rightward bias during embracing. Additionally, this general motor preference is strongly modulated by emotional contexts: the induction of positive or negative affect shifted the rightward bias significantly to the left, indicating a stronger involvement of right-hemispheric neural networks during emotional embraces. So, results show that strong feelings lead to a shift left. This fits with the fact that emotions are predominantly processed in the right hemisphere, which controls the left half of the body.
Hugs’ effects on human health
Although research on the evolutionary and social significance of hugs is relatively new, some effects of hugging have already been discovered physiological parameters such as blood pressure, which drops, and on concentration of oxytocin, which increases. Correlational studies found predominately that frequent hugging is also associated with lower levels of proinflammatory cytokines, or improved immune system response to a cold virus.
The role of the oxytocin is important: this causes a reduction of cortisol concentration, which controls the body’s immune reactions. During acute stress, this hormone reduces the immune reaction: the person does not develop symptoms of the disease and being able to continue to “work”.
Even if the research in the field of neuroscience is still in the early stages of hugging, this very ancient ritual has a role important not only in the communication of emotions, but also in the promotion of well-being physical and psychological.
References:
[1] https://doi.org/10.1007/s00426-018-0985-8
[2] “A stretto contatto” – Sebastian Ocklenburg, Julian Packheiser – Mind (december 2024).
