We don’t always pay attention and over the years we’ve probably learned to stop our tongue from sticking out just like that, but often while we’re concentrating on a specific activity or trying to make some precise movement with our hand, we also stick our tongue out. What exactly is the connection between hand movements and our mouth?
The social meaning of speaking on purpose may vary according to culture and situation. In Tibet, sticking out the tongue is a sign of respect or blessing. In other ancient cultures it symbolizes cruelty and defiance and every day it is used by us to express a variety of feelings such as disgust, embarrassment or contempt. There are also those who have made a career out of it, according to Miley Cyrus who explained that she started the act to deal with her insecurities. But what does this not always polite action mean when it occurs in other situations and not on purpose?
One in the mouth, one in the hand
Our tongue and hand movements are interconnected on an unconscious level, and the strange interaction between them occurs even though the two are controlled by completely different nerves. A person who suffers from a spinal cord injury and paralyzed hands does not lose the ability to speak. One of the basic explanations for sticking out the tongue at the same time as hand movements is called motor overflow. That is, threading a needle or performing other fine motor skills, is an action that requires cognitive effort and it floods the brain circuits that affect nearby circuits, activating them as well.
According to a 2015 study by neuroscientist Dr. Gillian Forrester, motor overflow can occur during complex activities that involve using our hands, causing some of us to stick out our tongues. Forrester and her team followed a group of four-year-old children as they performed motor tasks. Subtlety. In all of them, the children stuck out their tongues mainly in moments that required high concentration. The researchers point out that sticking out their tongues is not only a matter for children, and adults also make unconscious mouth movements while performing manual tasks. The interesting finding was that the tongue in most cases was biased towards the right, which indicating that it is controlled by the left hemisphere of the brain, the side responsible for language processing.
How are motor skills related to our ability to speak?
But, it turns out that the hand-to-mouth relationship is a little more complex. According to Douglas Fields, professor of neuroscience, when you look at the neural wiring of the brain, you can see that the areas that control the tongue are not that close to the area that controls the fingers. The connection between the tongue and the hands must then be somewhere else in the brain, probably in an area where complex neural circuits perform more sophisticated functions, such as our ability to speak.
The automatic connection between the hand and the mouth is so innate that we are usually not aware of it, but we do it all the time. Fields claims that the coordination between the tongue and the hand is deeply rooted in the unconscious neural circuits of the brain, and probably originates from the eating movements of our ancestors from hand to mouth alongside the language development process. It can be assumed that it started with hand gestures, and they were gradually combined with appropriate sounds and sayings.
According to Fields, there is partial overlap in our neural networks between language and motor skills and high fine motor skill predicts good linguistic ability. Indeed, several studies have suggested that brain regions that control certain language functions, such as processing the meaning of words, are also involved in fine motor control. A study published in 2019 revealed a correlation between good syntactic ability and motor skill and there is also evidence that early motor skills may influence language development and motor developmental delays can predict later language problems.