People who can’t see the numbers

We often say “seeing the world through the eyes”, but in fact the eyes only play the role of “seeing”. To understand what the eyes see, you also need your brain to interpret. Since “seeing” and “perceiving” are carried out through the eyes and the brain respectively, and the brain often “distorts” what it sees, which creates visual errors. In life, we are often “cheated” by our brains, which creates visual illusions. Du Fu has a poem, saying: “The clouds in the sky are like white clothes.” “Floating clouds” is what Du Fu sees, while the “white clothes” is just a visual illusion created by his brain’s interpretation.

Recently, the Proceedings of the National Academy of Sciences announced a special patient. The patient code-named RSF has perceptual distortions due to neurological diseases. The numbers 2 to 9 are invisible. It is the only known invisible in the world. Figures of people.

In RSF’s eyes, the numbers from 2 to 9 are not numbers, but a bunch of messy codes. In other words, there is no problem with the patient’s vision, mainly because of an error in the perception pathway. RSF was not born like this. He could see the numbers, but since 2010, he has often experienced headaches and accompanied by temporary blindness. After consultation, the doctor diagnosed it as cortical basal ganglia syndrome, which is a neurodegenerative disease that can cause movement and language dysfunction. However, during the treatment of RSF, the doctor found that he could not see the numbers from 2 to 9.

What is even more confusing is that RSF not only can’t see the numbers, but also shields objects distributed around these numbers. The Johns Hopkins team discovered during the research that RSF can recognize the letter “B” which is very similar to the number “8”, but the number “8” is a bunch of garbled codes in his eyes. In addition, if the numbers are drawn in the form of line boxes, and the patterns that RSF can recognize under normal conditions are drawn in the line boxes, these patterns will also become a bunch of messy codes in his eyes because they are too close to the numbers.

Subsequent research results also showed that RSF could not recognize the numbers from 2 to 9 either singly, consecutively, or mixed with letters. But more complex symbols, such as “#” “¥”, etc., he can easily recognize. In order to eliminate the interference of other factors, the researchers changed the color, size, display time, and even the contrast of the digital image, but to no avail. After many experiments, the researchers finally came to the conclusion: RSF really cannot perceive the numbers from 2 to 9.

Why can’t RSF see the numbers from 2 to 9?

In order to solve this problem, the researchers carried out further experiments. They put the identical portraits in the line boxes of letters and numbers respectively, and the RSF will all produce similar brain waves. This shows that RSF’s brain processes this information, but RSF does not realize that the brain has processed the information. The author of this paper published in the Proceedings of the National Academy of Sciences, David Rosslein, said: “RSF is also the same when looking at numbers. His eyes see 8 and his brain also accepts and processes the visual information of 8. But in In the last step, there was a problem with the nerve supplying visual awareness, so he could not feel the processed information.”

At present, researchers are still not clear about the operating mechanism behind the phenomenon of “invisible numbers”. There is a speculation that there is a problem with the semantic memory of RSF. This memory is related to common sense, and the cognition of the pictophone of characters is particularly important. In order to help RSF recognize the numbers during the treatment, considerate researchers designed a new number shape system for him to refer to the numbers from 2 to 9. In short, it will take a long time for researchers to find the specific root cause of the disease.