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What are cognitive biases?

Your brain evolved to protect you. Here's how.

What are cognitive biases?

“We have a basic biological imperative to connect with other people. That directly affects the release of dopamine in the reward pathway. Millions of years of evolution are behind that system to get us to come together and live in communities, to find mates, to propagate our species. So there’s no doubt that a vehicle like social media, which optimizes this connection between people, is going to have the potential for addiction.”
–Dr. Anna Lembke, Associate Professor and Medical Director of Addiction Medicine, Stanford’s School of Medicine, in The Social Dilemma
Our brains use shortcuts to navigate the complex world around us and keep us safe and healthy:
  • We pay more attention to fearful, dangerous stimuli to stay safe.
  • We remember things that hurt us more than things that help us so we can predict future consequences.
  • We tend to follow the popular opinion of those around us to build stronger communities around shared ideas.
But these shortcuts don’t work perfectly in every situation. They can become cognitive biases, or ways in which our brains’ patterns make us vulnerable to errors in judgment, manipulation, and exploitation.
To understand this better, let’s do an experiment. Take a look at the image below. Which labeled square is darker: A or B?
The image shows a checkerboard with a green cylinder in the top right corner. The green cylinder is throwing a shadow over square B, which appears to be much lighter than square A.
Edward H. Adelson, 1995: Checkershadow Illusion.
The squares are actually the same color.
The difficulty in identifying this comes from your brain helpfully analyzing the colors, the shadows, and the shapes and viewing the picture as a three-dimensional scene.
Your brain views square B as a light-colored square that happens to be in the green cylinder’s shadow. Your knowledge that squares A and B are the same color doesn’t change your perception.
The image shows a checkerboard with a green cylinder in the top right corner. The green cylinder is throwing a shadow over square B and not over square A. Two gray lines are drawn connecting squares A and B and making it clear that they are the same color.
But when we draw lines of the same color through both squares, the shortcuts your brain was using no longer work. Now the two squares are clearly the same color.
Even if you understand how the trick works, a few carefully chosen design elements (color, shading, shapes, and patterns) take advantage of our brain’s helpful shortcuts for processing what we see. What we perceive to be true depends on the context in which we see it. This is cognitive bias in action.
Let’s look at another example: the Solomon Asch experiment on social conformity. Subjects were asked to match a reference line (on the left) to one of three comparison lines (on the right):
The image shows two boxes. The first has a single black line in it. The second has three lines. The line labeled A is the shortest, the line labeled B is the longest, and the line labeled C is a medium length and appears the same length as the line in the first box.
Which comparison line is the same length as the reference line?
The correct answer is Line C. Seems obvious, doesn’t it? People in the experiment correctly matched those two lines more than 99% of the time—when they were on their own.
Do you think you would still have answered C if several other people answered A or B? That’s what the experiment explored. When multiple actors were added, and they gave the wrong line as their answer, over 36% of the experiment participants chose the wrong line!
This finding may be surprising: social reality can override physical reality. This is a form of conformity bias: we tend to want to conform to the social norms around us.
Conformity bias can intersect with confirmation bias—the tendency for our brains to collect evidence that supports our existing viewpoints—compounding our tendency to favor people we already identify with: our friends, family, coworkers, or others who share our interests or opinions. You’re more likely to react favorably to a viewpoint coming from a group you identify with than a group you don’t identify with.
The Solomon Asch experiment on social conformity suggests that without realizing it, many people conform to initial perceptions and social norms, selectively ignoring contradictory evidence.
This has profound implications:
  • First, that some people’s behavior can be manipulated by their social environment.
  • Second, that the technology that shapes our social environments has immense power over what we say we believe.
  • And finally, that our democracies are vulnerable to technologies that manipulate consensus.
Social conformity bias and confirmation bias are important cognitive biases to consider in the context of social media, but they are just two among many. A motivated person or product can trick us in lots of ways, and that happens all the time because—whether it's shocking advertisements, addictive snack foods, or persuasive technology—tricking our brains is highly profitable.

Want to join the conversation?

  • blobby green style avatar for user Na KiyaB
    1. When we use social media repeatedly, it begins to train us, our thoughts, feelings, and motivations are shaped by powerful technology designed to keep us engaged.
    2. Social media creates an environment in which we are constantly comparing ourselves to others.
    3. They utilize apps, social media and other technology to raise awareness, recruit activists and organize protests.
    (3 votes)
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  • male robot hal style avatar for user Brave Tiger
    Some of the claims made from this article seem far-fetched, but I don’t think that the experiments are true at least some of the claims are true.
    (1 vote)
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