Psychogenic Blindness: Eye-Poppin’ Mind-Bogglers

No need to rush for an eye checkup in case you’re seeing Tetris-like shapes or Tetriminos everywhere, even if you’re not playing it. You’re only experiencing the “Tetris Effect” and there is nothing to worry about it. So, moving on, we have another bizarre case to crack and we have to perform an eye checkup to solve it.

Here is the scenario. What if after being blind for years, you’re suddenly able to see on an occasional basis? Now you see it, now you don’t.

This is what happened to a woman in Germany, whom they called as B.T. At her 20s, she had gone blind because of an accident. In clinical terms, she suffered from cortical blindness. She was also diagnosed with dissociative identity disorder.

After a psychotherapy session with Dr. Bruno Waldvogel in Munich, one of her ten personalities was able to read a few words in a magazine’s title page. Her doctors later found out that she was only blind psychologically or she has what is called psychogenic blindness.

What is psychogenic blindness?

Instead of defining it, let us differentiate an organic or clinically blind person vs. someone with psychogenic blindness. This is a type of eye checkup you can absolutely do at home. However, an eye doctor or an ophthalmologist has the final say on this subject matter.

According to the study conducted by Dr. Neil R. Miller, M.D., entitled “Neuro-Opthalmologic Manifestations of Psychogenic Disease”, here are ways to test the visual acuity loss of a patient:

  • Look directly at the person

A person with organic blindness will look straight at you while a psychogenic blind person will often look at other direction.

  • Using a rotating optokinetic drum:


Rotate the drum in front of the patient who has both eyes open. Note that in this experiment only one eye has a problem. Cover the unaffected eye with the palm of the hand immediately. The eye that has psychogenic blindness continues to show a jerk nystagmus.

What is nystagmus? Based on the American Optometric Association’s definition, it is a vision condition in which the eyes make repetitive, uncontrolled movements, often resulting in reduced vision.

  • Using a mirror:

Place a large mirror in front of the patient and ask him to look ahead directly. Twist the mirror back and forth. The patient will show a nystagmoid movement in the eyes because they cannot avoid following the moving reflection of the mirror.

  • Fingertip touching:

Instruct the patient to touch the tips of their point fingers. This is not a vision acuity test but rather it tests the proprioception of the patient. An organic blind person can easily do this whereas someone with psychogenic blindness cannot.

  • Signing a signature:

Same as the fingertip touching test, a person with psychogenic blindness will have difficulty doing this and may produce a “doodled” signature. Otherwise, he can do this without difficulty.

  • Pupil reaction:

The pupils of a psychogenic blinded person still react to light simulation whereas a naturally blind person must not be affected.

  • Bonus trivia: Patients claiming complete or nearly complete blindness often wear sunglasses. Now you know where sunglasses for sale in the Philippines come in handy in other “ways”.

What happened to B.T.? Based on an article in, “…she almost entirely regained her ability to see.” Thanks to the therapy she went through.

The Tetris Effect: Eye-Poppin’ Mind-Bogglers

No eye checkup could ever fathom this bizarre medical/psychological condition. It may be a trick of an eye or simple case of hallucination or mere illusion, yet it has some sort of scientific explanation. Or maybe it is all in the mind. Blame it to our brain’s plasticity, the ability to shrink and thicken in response to repetitive external stimuli. The brain is really the “control center” of our body because it can easily manipulate us even against our will and sometimes, even subconsciously.

Here is a condition those young at heart and kids who love to play video games will be curious about: the “Tetris Effect”.

Who among you readers aren’t familiar with Tetris? (Don’t you dare raise your hand.) Tetris is a popular game in the 80’s created by Alexey Pajitnov and its birthplace is in Moscow, Russia. How did he come up with such a name? says it is combination of “tetra” (the Greek word of “four”) and “tennis” (the inventor’s favorite sport). It is inspired by a mathematical puzzle game called Pentomino. This game made the Nintendo’s handheld gaming system Game Boy popular. Now it is made “new and improved” to invade the virtual memory of our smartphones and possibly the memory bank of our brains all over again.

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Tetris Blitz by Electronic Arts

The game is fairly simple. You have different colorful shaped blocks that you need to stack to one another in a way it would not overlap in order to “vaporize” the blocks in a single line. Academic experts categorize it as a visual-spatial problem-solving computer game, or a fancy name for “this game teaches you things without you knowing it”.

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Tetris Game Boy by Nintendo

But what in the world is the “Tetris effect”? Is it a post-game experience or the aftereffects of it? This somehow rings true. According to, the “Tetris effect” occurs with any repetitive task that involves particular movements, shapes or colors. It is not just only Tetris, but it can also happen while playing Angry Birds, Candy Crush, and nightmarishly, Flappy Bird (gasp!).

Imagine seeing Tetriminos everywhere; those flying birds or the menacing piggies; those colorful candies; and that annoying red bird launching towards green obstacles. You can also apply it in everyday real-life situations like loading the dishwasher, organizing your shelves or you may check this out.

tetris effect - adult.png

Even if you close your eyes or before visiting dreamland (the state of hypnagogic stage of sleeping), you may see behind your eyelids falling colorful blocks. (What a joy.) This is how you experience the “Tetris effect”.  And no, you don’t need to schedule for an eye checkup to make it go away. explains that it is an unconscious effort of your brain to practice and master a repetitive task even when you’re not doing it. Yep, that is our brain, busy as ever. Our so-called “gray matter” is actually helping us to get better at gaming (i.e. Tetris).

Fortunately, the “Tetris effect” has a positive effect in our mental health. A study posted at, found out after their subjects practiced (played?) Tetris for 30 minutes a day, their brain had “thickened”. This is more likely a sign that their brains have improved its memory capacity. In addition, says it also makes the brain more efficient and helps those who suffer from post-traumatic stress disorder. So, annihilating those pesky blocks has a good outcome after all.

Aaargh! Eye checkup, now!

Wait for more strange medical conditions that our eyes or brains could trick us! The next will definitely need an eye checkup to decipher.

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