A recent and very interesting scientific research shows two surprising facts. The first is that chewing improves cognitive function, memory, attention and concentration and the second is that to make the most of this connection between chewing and the brain we must observe our pupils. But let's proceed in order and try to understand what the study says. The research was published in the journal Frontiers in Systems Neuroscience by a team from the University of Pisa (Tramonti Fantozzi et al, Front Syst Neurosci, Dec 2021).
The connection between chewing and the brain
Studies carried out in recent years have already demonstrated that chewing improves cognitive functionality. Even just the action of chewing gum can improve attention and concentration, reduce reaction times and increase the speed of neuronal processes. Chewing, in fact, improves oxygenation of the brain. It is believed that this action is due to the ability of chewing to keep stress under control and to regulate, through the activation of the trigeminal nerve, the ascending reticular activating system, or ARAS. ARAS is a complex of neurons in the central nervous system responsible for controlling wakefulness and attention. The point is that this trigeminal activation and its impact on cognitive function also affects the network of neurons that regulate pupil size. If we add to this that an asymmetry in the size of the pupils can sometimes be a sign of an alteration at a cognitive level, as shown by recent research, it is legitimate to hypothesize that there is a link between the difference in pupil size, chewing and cognitive function. To shed light on this aspect, Italian scientists have developed the research we are talking about today.
Attention when an eye pupil is smaller than the other, the study
Scientists recruited 30 volunteers, including 21 with a difference in size between the two pupils. Study participants underwent tests to evaluate cognitive function and medical examinations to study the activation of the trigeminal and brain areas before and after performing a chewing exercise. What has emerged is that the side of the mouth corresponding to the smallest pupil is the one least used for chewing. This is because the ARAS neuron system tends to try to bring balance during chewing, stimulating the use of both sides, and the signals it sends cause the pupil of the less used side to constrict. Scientists have also been able to see that chewing on the side that is less used can improve cognitive function, which is not the case if you chew only on the side that is most used, which loses sensitivity and activates the brain to a lesser extent. Not only that, the Pisan scientists have also managed to understand, through medical diagnostic techniques, that an asymmetry of the pupils caused by incorrect chewing also causes an asymmetry in the functioning between the cerebral hemispheres and the hippocampus, the fundamental part of the brain for memory and learning, is affected.
Italian research has therefore added a very important element to the research carried out so far. And that is that it is true that chewing, during lunch or simply gum, is a tool at our disposal to improve cognitive functionality and avoid alterations in the functioning of the brain, but it is also true that we must avoid having a side of the mouth more used than the other to present this beneficial effect. Therefore, it is important to take care of the health of the mouth and try to avoid chewing only on one side but prefer both, alternating them. In this way it is possible to rebalance chewing, reduce the difference in the pupils, which in fact is only a signal of something altered, and improve attention, cognitive functionality and the work of the hippocampus.