In an ‘impossible’ feat, the student manages to contract and dilate the pupils just by thinking

A man is attracting the attention of science by be able to change the size of your pupils just by thinking about the action.

The doctors were surprised and excited about the talent, considered “impossible”, of the 23-year-old student. The case is unique in the world. Previously, people with similar ability used some type of strategy to dilate or contract your pupils.

For example, they might consider looking at direct sunlight to make them smaller or going into a dark room to make them bigger.

But, according to doctors at the University of Ulm (Germany), the author of the feat, identified only as DW, doesn’t seem to use any “artificial” method. The case report was published in the scientific journal “International Journal of Psychophysiology/Elsevier”.

A man can contract and dilate his pupils just by thinking about the specific action
A man can contract and dilate his pupils just by thinking about the specific action Photo: Reproduction/International Journal of Psychophysiology/Elsevier

In an interview, DW did not describe exactly how he does it, telling doctors:

“It’s difficult to explain, as difficult as answering the question ‘What does it feel like to move a finger?’ something, Making it bigger is like letting go totally, relaxing the eye. I have to focus my attention on my eyes and my field of vision and then create tension or relaxation. This is easier for me if I keep one eye closed. I can tell my pupil size is changing because of the change in my vision.”


Pupils change in response to light, focus, excitement, medication, brain damage, emotion like fear, and recreational drugs. The pupil’s function is to change the amount of light that enters the eye. The muscles in the colored part of the eye (iris) change size depending on the stimulus, contracting and relaxing. Movement is automatic and cannot be controlled. At least that’s how the doctors thought.

DW realized he could change pupil size on his own at age 16, when he used to play a lot of computer games. He contacted one of the article’s authors to tell him about his strange ability, which prompted them to take tests. DW proved that can dilate your pupils up to 2.4 millimeters in diameter and contract them to 0.88 millimeters in diameter.

In addition, DW was able to hold an object very close to his eyes and bring it more into focus by further contracting his pupil, even though he was already in “maximum” natural constriction.