The Upstairs and Downstairs Brain

Our amygdala (pronounced uh-MIG-duh-luh) is about the size and shape of an almond and is part of the limbic area, which resides in the downstairs brain. The amygdala’s job is to quickly process and express emotions, especially anger and fear. This little mass of gray matter is the watchdog of the brain, remaining always alert for times we might be threatened. When it does sense danger, it can completely take over, or hijack, the upstairs brain. That’s what allows us to act before we think. It’s the part of the brain that instructs your arm to stretch out to protect your passenger when you’re driving and have to stop short.

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acting or reacting before we think isn’t usually so good in normal, everyday situations, like when we storm from our car and yell at another parent for breaking the no-waiting rule in the carpool pickup circle.

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that’s what we call “flipping our lid,” and it’s how the amygdala can get us into trouble: it takes over and relieves the upstairs brain from its duties. When we’re not truly in danger, we want to think before acting, instead of the other way around.

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When your three-year-old erupts in anger because there are no orange Popsicles left in the freezer, his downstairs brain, including the brain stem and amygdala, has sprung into action and latched the baby gate. This primitive part of his brain has received an intense surge of energy, leaving him literally unable to act calmly and reasonably. Massive brain resources have rushed to his downstairs brain, leaving little to power his upstairs brain. As a result, no matter how many times you tell him that you have plenty of purple Popsicles (which he liked better than orange last time anyway), he’s probably not going to listen to reason in this moment. He’s much more likely to throw something or yell at anyone nearby.

Our instinctive, more primitive brain overrides our logical, more advanced from time to time. Children are even more prone to it.