Whether it's a sigh of relief, or a sigh of grief, we all sigh throughout the day. But what's the actual purpose of sighing? Psychology Today points to a few studies that suggest it's not only a sign of communication but a breathing method that makes us feel better.
A sigh can have all types of meanings. It might be a sign of sadness, frustration, or even plain old annoyance. One study suggests that sighing tends to have a soothing effect on the person actually doing it. Psychology Today describes it like so:
By studying breathing patterns of participants for 20 minutes while sitting quietly, the authors found that during the time preceding a sigh, breathing begins to vary, changing in speed or shallowness.
When breathing in one state for too long, Vlemincx says, the lungs become stiffer and less efficient in gas exchange. Intermittently adding a sigh to the normal pattern, then, stretches the lung's air sacs (alveoli). This feeling may give one a sense of relief.
That said, we don't perceive a sigh the same way in others as we see it in ourselves. In one experiment, researchers asked participants to also share what they thought when other people sighed:
In each of the four cases, participants imagined people to be sighing out of negative feelings 10 times more often than for positive reasons. Furthermore, when others sigh, it's perceived as sadness — but when we sigh, we do so out of frustration.
A sigh is one of those subtle cues we all give off, and if you're ever in a conversation with someone who sighs, it might be a good idea to second-guess your intuition that the person is sad about something.
Why Do We Sigh? [Psychology Today]