Ever experienced the tetris effect? Have you ever had a crush on someone and suddenly started seeing them everywhere? Whether if you’re walking around campus, at one of the cafes, or out having fun – they are everywhere. Isn’t it eerie? It’s as if the universe is giving you a sign…or maybe it isn’t? Well, let’s unravel how this phenomenon is not magic. It’s just psychology.
What is the Tetris effect?
Short answer
This is called the Tetris effect. To put it simply, it is the brain’s tendency to rewire itself based on whatever we repeatedly think about, focus on, or invest ourselves emotionally in. We start to see more of what we are already paying attention to.
Long answer
The term ‘Tetris Effect’ was first popularized after a study by Robert Stickgold and colleagues at Harvard Medical School found that people who played Tetris (A block game) for hours began experiencing hypnagogic imagery (vivid mental images that appear right before they sleep) consisting of falling Tetris blocks. It was said that playing the video game for extended periods made them see it in their thoughts, dreams, and even real-world objects. Interestingly, even amnesic patients, who could not consciously recall playing, still reported Tetris imagery during their hypnagogic states (the phase between wakefulness and sleep). This suggested that visual and cognitive exposure was strong enough to alter subconscious processing.
This phenomenon is based on neuroplasticity, the brain’s ability to rewire itself based on repetitive experiences. The more you engage with a thought or activity, the stronger the neural pathways associated with it become.
Enter – Frequency Illusion
In order to fully explain how this phenomenon of seeing someone everywhere works, we need to understand the concept of frequency illusion (also known as the Baader-Meinhof phenomenon). This effect is explained by two cognitive processes –
- Selective attention – This is the ability to select and focus on certain stimuli in an environment, while simultaneously ignoring the peripheral or distracting information. In nature, humans have an unconscious cognitive ability to filter information and choose which stimuli they would like to place their attention towards. So here, once you have noticed something, your brain subconsciously begins to ‘scan’ for it.
- Confirmation Bias – This, on the other hand, is the tendency to seek out information that confirms our existing beliefs, with a complete disregard for any contradictory evidence. Therefore, when your attention is on this stimulus you will start noticing it more, which will confirm your idea that it is occurring more frequently, when in reality, the frequency has not changed at all.
First, attention is triggered. Second, repeated noticing creates the illusion of increased frequency.
A strong example is the 11:11 concept. Where it is believed that seeing this number is often interpreted as a message from the universe. Logically, we know that in a day 11:11 occurs twice, so even if you see it once a day every day you assume it is a sign. However, it is frequency illusion that is guiding this cognitively. Even though you might look at the clock several times during the day, you end up only focusing on the instances in which you actually see 11:11, which is why you are illusioned into believing that you see it more often
How they work togetherÂ
Now combining the Tetris Effect and the Frequency Illusion shows us how something small can begin to reprogram the brain’s perception of reality and create an obsession. One works from the inside out where repetition creates patterns in your neural pathways. The other works from the outside in where your brain begins spotlighting those patterns in the world around you. These together create a self-reinforcing loop. The more you think about something/someone the more space it takes up in your working memory. This makes your brain start prioritizing that information, making it quicker to notice it. What follows is a kind of perceptual echo chamber –
You think about it → you notice it more → it feels more important to you → you keep thinking about it.
This cycle strengthens itself with every repetition and rewires how you pay attention, what you notice, and how you interpret the world around you. In the end, the obsession doesn’t just filter your reality; it begins to reshape it.
Conclusion: hacking the game
Now that you are consciously aware of what is happening cognitively, the trick lies in using this loop to your advantage. If your brain is going to rewire itself based on what you focus on, then it’s a no-brainer that what you choose to focus/obsess over is the key. Whether it’s a goal, a habit, or a mindset, repeated affirmation/attention to it can train your brain to see more of it and believe in it more deeply.
By being intentional and conscious with your focus, you can master the hack of the same feedback loop that reinforces anxiety, fear or fixation and redirect it towards growth, purpose, or self-belief. The brain is always adapting, whether you are conscious of it or not. The question is: what are you feeding it?
Because in the end, it’s not just about seeing more of what you already notice every day. It’s about becoming the kind of person who naturally notices and attracts the life you want. Always remember, you become what you think about. You are what you attract.