Whether it’s constant rain, a heat wave or a new love: there are many things that make us sigh in our everyday lives. A habit that scientists say is extremely important for survival.
About twelve times an hour we supposedly sigh unconsciously – and breathe in much deeper than normal. To be precise, we pump twice as much air into our lungs as we would in a normal breath. Researchers have been studying this phenomenon for years, and now US scientists have deciphered the mechanism behind it. Jack Feldman, a neurobiologist at the University of California (UCLA), examined the process and published the results of his study in the journal “Nature”.
What is behind sighing?
The human sigh center is located in the brain stem, where the respiratory center is also located. The breathing itself is automated. However, two tiny arrangements of neurons cause occasional deviations from normal breathing – and these sighs are necessary to ensure that even remote areas of the lungs are supplied with oxygen. The purpose of the sigh is therefore to maintain the exchange of air and re-inflate collapsed alveoli. “When they collapse, they disrupt the lungs’ ability to exchange oxygen and carbon dioxide,” explains Feldman. So sighing is vital.
What do biologists say on this topic?
Sighing also plays a life-sustaining role in infants, as scientists at the University of Bern found out in a study. They found that babies take a particularly deep breath every 50 to 100 breaths, which is controlled by the breathing centre in the brain. The sighing helps babies to develop a regular and stable breathing rhythm. As soon as breathing becomes too slow, the brain adjusts – and interrupts the rhythm with a sigh.
When and why do we sigh?
In general, we sigh in case of grief, stress or simply out of relief. But why in these situations in particular? There is no clear explanation for this. Ulfried Geuter, psychotherapist from Berlin, however, sees the sigh as a kind of reset button for the psyche. Emotions and tensions can be discharged, we can take a deep breath and take a deep breath once in a while to calm down again.