You have probably heard it said many times that eyes are the window to the soul. But that’s not all! Scientists have found evidence that eyes may be a gateway to a person’s brain. but how?
The pupil is the entrance to the light path into the eye. Researchers think that light may not be the only input to the pupil. According to previous research by scientists, pupils change shape due to fatigue, high or low light, arousal and even emotions. The importance of the pupils is so great that many false or even narcotic tests are based on the size of the pupils.
The Georgia Institute of Technology Laboratory, after conducting numerous studies, found that changes in the pupil size of individuals indicated their internal characteristics; One of these characteristics is people’s intelligence. In other words, scientists believe that the level of intelligence of each person can be detected through his pupil.
To test the pupil hypothesis, the scientists performed several different experiments. In one of these experiments, a number of people were asked to take an intelligence test; The response of these people was then compared with their pupils. The results were undeniable! People with larger pupil scores performed better on this test. In this test, skills such as intelligence, reasoning, concentration and memory were tested and the results showed that the size of the pupil is directly related to these skills.
The relationship between intelligence and pupil size was discovered when scientists were looking at differences in memory power in different people. In this experiment, pupil dilation was used as an effective factor on memory. At first, when we compared the relationship between pupil size and student intelligence, we were unsure of our findings.
At first we did the experiment on a small scale and then we used more people during the experiment to give a definite opinion. In one of the experiments on this hypothesis, we used more than 500 people between the ages of 18 and 35. In this experiment, using an eye tracker, a device that uses a powerful camera and computer to photograph the light of the pupil and cornea, the pupil size of the participants was measured.
At the beginning of the experiment, the pupil size of each participant was measured at rest. Each participant then stared at the blank computer screen for four minutes; During all this time, the device was recording the size of each participant’s pupil. Finally, we calculated the average pupil size of each person’s eye.
For further explanation, we should add that the pupils are in the black part and in the center of the iris (colored part) of the eye. Pupil diameters can vary from 2 to 8 mm; In other words, the expansion and contraction of the iris muscles change the size of the pupil. It is true that the pupils change size due to too much or too little light, but we placed all participants in a dimly lit environment for more validity of the experiment.
Subsequent tests included intelligence tests, the ability to make decisions in the face of new situations, memory capacity and the ability to remember information, and the degree of concentration and attention when faced with misleading factors.
For example, in an attention control experiment, participants had to ignore a glowing star in the corner of a computer screen and avoid looking at it; But they have to watch a letter on the opposite side of the star, although the word disappears after a few seconds and it becomes very difficult for the participants to ignore the star in the corner of the page. The reason this experiment is so difficult is that humans are inherently ready to react to the movement of objects in their field of vision; This explains the success of early humans in hunting. In fact, we asked the participants in this experiment to ignore this inherent characteristic and desire to react by ignoring the star.
Overall, the results of all these experiments showed a mysterious relationship between the participants’ pupils and the brain. It is interesting to know that the pupil size of individuals was inversely related to age; Older participants had smaller, more limited pupils.
In this experiment, when we compare participants with the standard age gap, we simply find the relationship between pupil size and IQ.
Why is the size of a person’s pupil directly related to their IQ?
To answer this question, we must first understand the brain processes when observing objects. Pupil size is related to activity in the locus ciruleus nuclei in the brain bridge. The brain bridge is the part of the brainstem that has large nerves connected to other parts of the brain.
Locus ciroleus secretes norepinephrine, which acts as a neurotransmitter and hormone in the brain and body. This hormone regulates processes such as perception, attention, learning and memory. In addition to monitoring these actions, this hormone is responsible for connecting different parts of the brain to each other and can execute inhibitory or stimulatory messages by affecting its target organ.
Impairment of brain activity and its analysis due to injury, accident or old age can have many consequences on a person’s learning. One of the problems that results from brain dysfunction is Alzheimer’s disease, attention deficit disorder, hyperactivity, and so on. In fact, the key to the body’s function is coordination, and the brain uses most of its energy to control this coordination and to organize the organs. This happens even when we are not doing something; Like staring at a blank computer screen for several minutes in a row.
But the main hypothesis in this article is that people with larger pupils are thought to be doing more with their locus ciruleus. In fact, Locus ciruleus helps the brain at rest to better recognize and function.
We still need a lot of research to find out the truth behind the pupil, but all we know is that these similarities are not coincidental and the pupils have many secrets.