Why do our brains store traumatic memories better than happy ones?



Why do our brains hold onto traumatic memories more than happy ones?

I understand that traumatic memories can and most likely will change someone’s core being, but why exactly does the brain remember them easier than happy memories?

In: Biology

The brain is wired to remember negative experiences better as a survival feature. Remembering the time the lion chased you will make you more on guard when out on the plains, making your survival more likely.

This translates to any form of danger: abuse, bombings, bullying. The brain doesn’t distinguish between a bully and a lion- both can be a threat.

Because the potential cost vs reward is different.

Eating a tasty meal with friends: good dopamine release, makes you feel good for a few hours.

Breaking your leg: two months of pain.

The humans who were able to store negative information were the humans who were more likely to anticipate or survive threats- most humans today show this trait as well.

Good things happening are not as dangerous to the survival of a human than bad things, we don’t need to keep on the lookout for good events.


As a kid, you won a free ice cream at a fair. It’s awesome and cool. You probably don’t think about it much.

versus: As a kid, you won a free ice cream at a fair. It’s awesome and cool- but then you tripped because you didn’t tie your shoes and your ice cream was all over the ground! It sucked, and you’ve since learned to make sure your shoes are tied.

This isn’t a life or death situation, but we are predisposed to avoid negative outcomes if in our control. This includes making assumptions about other people, eg: negative stereotypes.

Even animals have an easier time remembering one bad situation over a plethora of good ones. My dog was terribly afraid of rolled up newspapers. At the time, we were running around trying to whack flies out of the air, and had no clue why she was whimpering and ducking under the table. 14 years and no one had ever laid a hand on her, she was very loved. We had no idea why she was so afraid until my grandmother explained that the person she’d been taken from was “strict” (abusive). This poor dog saw the newspaper, and despite the love and care our family had shown her for over a decade, she still feared it. Her experience had shown her it was a bad thing, and by avoiding it she could avoid pain. It’s not rational behavior in the context of our home (albeit trauma rarely leads to rational behavior), but this behavior could have lent her a survival advantage if she was out on her own.

The reigning theory is that we need to remember bad experiences better than good ones. Good memories like beautiful sunsets are useless in survival; bad experiences like almost freezing teach you to prepare for the cold.

Meanwhile there seems to be universal phobias like falling from heights.