Dlaczego się uśmiechamy? Ekspertka UŁ w Światowy Dzień Uśmiechu

Why do we smile? The simplest answer is to cooperate and increase the chances of survival. It seems that in the process of evolution, those who quickly and easily inspire trust and a sense of security in their fellow humans have a greater chance of passing on their genes. Nice, friendly people have a greater chance of getting help in a dangerous situation. They can also, through their behaviour, evoke positive feelings in others. As Mark Twain used to say – "The human race has only one really effective weapon and that is laughter". Dr hab. Katarzyna de Lazari-Radek, Associate Professor at the University of Lodz who is a philosopher and an ethicist, an expert on well-being, happiness and pleasure, and the University of Lodz Vice-Rector for Internationalisation of Science and Education comments on the occasion of World Smile Day, which is observed on the first Friday of October.

Smile! Endorphin, serotonin, dopamine – an emotional cocktail that evokes positive feelings

Let's imagine that in the hall of the university we meet a friend whom we haven't seen all summer. Or, while browsing social media, we come across a video of a small sleeping cat with a round belly, or we are just leaving for our dream Erasmus mobility. In a split second, our brain perceives this data as positive, releases a whole set of hormones: endorphins, serotonin, oxytocin, dopamine and signals the facial muscles to contract into a smile. The contracting muscles send a positive signal back to the brain, which pours even more hormones into our bloodstream. This is the automatic way in which the process of feeling and showing joy and pleasure occurs.  

Happiness and satisfaction in the form of a smile are recognised and replicated the fastest

Nice, friendly people have a better chance of getting help in a dangerous situation. They can also evoke positive feelings in others through their behaviour. Observing such a person in the above situations, there is a good chance that we will also smile and experience joy. Although every day we observe different emotions in ourselves and others, it is happiness and satisfaction in the form of a smile that we recognize and replicate the fastest. There are many hilarious social experiments that show that a smile is the easiest to catch. Mirror neurons and empathy are responsible for this reaction.  

Smile – reduces stress, lowers blood pressure and slows down the heart rate

I have already mentioned the brain biochemistry that triggers feelings of excitement, pleasure or euphoria in us. It is wonderful to experience them. We like it when a smile turns into laughter, sometimes to tears. We tell jokes, we love comedy and stand-up comedy. Smiling reduces stress, lowers blood pressure and slows down the heart rate. Finally, when we are happy and relaxed, we are more willing to work, learn more effectively and are more creative. 

As reported by American scientists (seriously!) a smile works in this health-promoting way, even when it is fake. Our brain does not recognize our intentions but receives impulses from the contracting facial muscles responsible for smiling (e.g. by holding a pencil between the teeth). This means that facial expressions not only reflect our emotional state but can also change it. When we form our lips into a characteristic horseshoe shape, even in a forced way, the signals sent to the brain can lead to the feeling of positive emotions, such as joy or peace.  

This simple biological mechanism of informing our surroundings what mental state we are in is shared by many animals, although the expression itself varies by species. There is still no consensus among primatologists as to whether great apes express contentment using their mouths. There is, however, no doubt about what the energetic wagging of dog’s tail means. Cats purr, birds spread their wings, rats jump for joy. The non-verbal language of emotional communication is fascinating and worth observing and learning in order to better understand ourselves and the world around us.

a portrait photo of Dr hab. Katarzyna de Lazari-Radek, Associate Professor at the University of Lodz(photo: Bartosz Kałużny, Communications and PR Centre, University of Lodz)

World Smile Day was initiated by Harvey Ball, the known for creating the iconic smiley face symbol in 1963. This symbol is supposed to represent exactly what we want to see as often as possible in other people on a daily basis – a selfless smile and joy of life. Because as it turns out, the age-old saying “laughter is the best medicine” is not just a metaphor.

Text: Dr hab. Katarzyna de Lazari-Radek, Associate Professor at the University of Lodz, Faculty of Philosophy and History, University of Lodz

Edit: Communications and PR Centre, University of Lodz