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Why unfairness makes you rage

Welcome back to Inside Your Head 🧠, a weekly newsletter exploring why your brain makes you think, feel, and act the way you do, written by Dana Smith, Elemental’s senior writer and a former brain scientist. Forwarded by a friend? Subscribe here so you won’t miss the next one.

Of all the brain-exploding aspects of These Times, the thing that infuriates me the most is the unfairness of it all: who suffers disproportionately, who skates by unaffected, and who gets away with things that no one should get away with. The injustice and double standards in this world make me furious. You too? Turns out there’s an evolutionary reason that being treated unfairly is so rage-inducing — in fact, it’s one of the most primal sources of anger.

  • The phenomenon is called inequity aversion. Simply put, if you invest the same amount of effort as someone else, you should receive the same reward. This expectation can apply to equal pay for equal work, equal protection from the police officers your taxes have paid for (assuming you’ve paid them), or equal representation in the legal system you’ve adhered to in good faith. When this expectation is violated, you get mad.
  • Inequity aversion occurs in children as young as three and even in some species of animals, such as monkeys, birds, and dogs. The universality of the response suggests that anger in the face of unfairness is innate.
  • There’s an amazing video exemplifying inequity aversion in its simplest form from the research of primatologist Frans de Waal. In the clip, two monkeys perform a task in a lab. At first, the monkeys are given the same reward for the task — a piece of cucumber — and everything is peachy. But then the reward changes, and one of the monkeys receives a grape instead, a much sweeter treat. When the monkey still receiving the cucumber discovers the inequity, it THROWS THE CUCUMBER AT THE SCIENTIST IN PROTEST. (I have to resist this urge every time I read the news.)
  • De Waal proposes that inequity aversion arose in humans and other species to reinforce cooperation. Cooperative societies, whether they’re animal or human, depend on social contracts founded on fairness in order to function. If the social contract is broken, the unfairness is met with protests and punishment to nip the bad behavior in the bud.
  • Separating us from our primate cousins, humans don’t just get angry when we ourselves have been cheated; anger in the face of inequity can be felt on someone else’s behalf, too. Our preference for fairness causes us to punish those who have committed an injustice, even if we weren’t the victims. In fact, we’re so obsessed with fairness, we will pay a personal cost to avoid inequality for others.
  • In your brain, an area called the anterior insula gets turned on when you perceive unfairness. This region is involved in feelings of empathy, as well as a sense of disgust, suggesting you might actually be repulsed by inequality. The amygdala, an emotion-processing region, also gets activated in response to injustice, triggering feelings of anger.

When you feel the hot fire of injustice spreading across your cheeks, slap a bag of frozen peas on your face to cool off. Seriously. The cold shock will activate the “mammalian diving response,” which shuts down your body’s panic mode. This evolutionary response would ordinarily be triggered by jumping into a cold body of water, forcing the body to conserve energy and focus on breathing, but you can use the technique to chill out emotionally, too. Or you could just start chucking cucumbers.

  • 🐦 Crows know what they know — a higher level of intelligence thought to be unique to humans. Already regarded as one of the smartest species, new research suggests crows have a meta-intelligence that enables them to analyze the contents of their own minds.
  • 🔬 Black Americans are twice as likely to develop dementia but make up less than 5% of clinical trial participants. The African Ancestry Neuroscience Research Initiative aims to address racial disparities in brain disorders through more diverse genetic and molecular research.
  • 💊 Low vitamin D linked to a higher risk for Alzheimer’s disease. A longitudinal study of more than 1,700 seniors found that over the course of five years, people with high dietary vitamin D intake were less likely to develop dementia.
  • 🚨 A new clinical trial will test whether Parkinson’s disease can be treated with an infrared laser beam. Scientists hope the light, implanted deep in the brain, will help prevent brain cells from dying.

Thanks for reading! I’ll be back with another look inside your head next Tuesday. In the meantime, email or tweet me to let me know at whom you’re throwing cucumbers.

Health and science writer • PhD in 🧠 • Words in Scientific American, STAT, The Atlantic, The Guardian • Award-winning Covid-19 coverage for Elemental