Optical Illusion

Can our culture change our brains

How culture shapes our interpretation of reality

Illustration of an optical illusion

Which line is longer, A or B? Now suppose you asked this question to a cattle herder in Kenya or a hunter-gatherer on a small Philippine Island. Who would answer this question correctly? Who would be misled by the illusion? Around 1880, the young German psychiatrist Franz Carl Müller-Lyyer wanted to study how the human brain sees the world' Hei was only in his early thirties, but in his field, he was already a rising star. At that time, optical illusions were very popular in psychology. Frans wanted to leave his mark on the field.

Here is an excerpt from the book by Michaeleen Doucleff; Hunter, Gather, Parent.

"When the researchers looked at the results from other cultures, things got interesting. In some indigenous cultures, such as the hunter-gatherers of southern Africa and the farmers of the Ivory Coast, people were not deceived by the illusion at all.° They saw the two lines as they were drawn, as two lines of equal length. In all other cultures, susceptibility to the illusion fell between the two extremes; between the deluded Americans and the imperturbable Africans, people of fourteen other cultures thought the two lines were different in length but not nearly as different as the Americans thought.

The researchers hypothesized that the illusion most misleads Americans because we live in "constructed environments." or in right-angle environments. Blocks surround us. We see them everywhere we look. We live in blocks (houses), sleep in blocks (beds), cook on blocks (stoves), commute in blocks (trains), and fill our homes with blocks (chests of drawers, tables, benches, sideboards, etc.).

Scientists hypothesize that this exposure to blocks trains our brains to form the Müller-Lyer illusion on a particular way: when we see the two arrows, our brain takes a shortcut.* Subconsciously, we turn the two-dimensional lines on the page into the corners of three-dimensional blocks (or, more precisely, drawings of the corners). Why does this subconscious switch make us believe the top line is shorter than the bottom? Imagine that the two lines are the corners of a building. The line at the bottom, with the arrows pointing outward, resembles an angle that recedes from our vantage point or one that is farther away from us. The top line, with the regular arrows, looks like an angle facing us or closer to us. This causes the brain to stretch the bottom line because it appears further away from us than the top line. But in many cultures worldwide, people are not surrounded by blocks and right angles. Instead, they are surrounded by rounded, flowing shapes. Houses and buildings are often dome-shaped or made of more malleable materials such as reeds or clay. When these people go for a walk, they don't walk on sidewalks with lampposts (which make right angles). They move through lots of nature, such as planting trees, animals and landscapes. Nature does not like right angles. Nature loves flowing lines.

So when a San woman in the Kalahari Desert looks at the two lines of the Moller-Lyer Illusion on a piece of paper, she is not distracted by the arrows. Her brain doesn't automatically assume that these linens are 3D corners of blocks. Instead, she sees what's drawn on the page: two lines of equal length. By presenting the Muller-Lyer illusion to different cultures, the researchers exposed a huge crack in the foundations of psychology. Their results showed that the culture and environment in which you grow up profoundly shape the brain's basic functions, such as visual perception.

If that's true, can our culture change our brains in even more ways? Other "human commons" or "general principles" in psychology are not universal at all, but rather unique to Western culture due to growing up and living in a particular environment.

Another way to describe this idea is as follows. If being part of a culture affects something as simple as interpreting two lines on a page, then maybe our culture also affects more complex psychological processes. What does she do with our parenting philosophy or the way we view children's behavior? What if some of the ideas we consider universal when it comes to raising children are actually optical illusions created by our culture?"


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