For scientists, the size of your pupils measures your intelligence

The result of the study carried out by two researchers at the Georgia Institute of Technology: the size of your pupils measures your intelligence.

That the eyes are the mirror of the soul is a well-known saying. That the gaze can be intelligent or unintelligent, deep or empty is an observation that everyone has made at least once in their lives. And it is also a quirk of writers to spend words or whole sentences to connote or describe in depth the human eye and its actions. A glance can therefore be furtive, or in love, or perhaps filled with hatred. With the pragmatism that distinguishes them, the researchers have proposed instead a "mathematical" interpretation of the gaze, tying the size of the pupils to cognitive abilities, thus giving a possible scientific basis to both subjective first impressions and descriptive techniques in novels.

What is the research

The relationship between the size of the pupil, the hole located in the center of the iris that allows light to enter the eyeball, and cognitive ability would be directly proportional: the larger the hole, therefore, the greater the intelligence. The study, reported in the journal Cognition, was carried out by two research psychologists from Georgia, in the United States, employed at the Georgia Institute of Technology.

The analysis involved half a thousand people, aged between 18 and 35 years. A computer and a high-resolution camera were used to measure pupil diameter, while illumination was carefully kept constant throughout the observation. In fact, pupils react to the presence of light stimuli with a change in diameter (this fact, incidentally, has also made the results of some previous studies contradictory and uncertain, and they have never been able to prove the correlation beyond any margin of doubt).

A larger baseline pupil would therefore, according to the U.S. researchers, have a direct link to fluid intelligence, the ability to control attention and remember. During the test, the camera kept track of pupil size as participants retained information for a period of time, exercised their attention control skills, and thought and reasoned quickly.

What the correlation depends on

The researchers' suspicion is that the mysterious correlation runs through the "locus coeruleus," located at the top of the brain stem and having deep neural connections with the central nervous system. Larger pupils would thus be a sign of a locus that is "well-oiled" and capable of influencing the performance of high-capacity individuals.

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Giuseppe Giordano