The Amygdala: Our Brain’s Alarm System
When we are not in a state of distress, our hippocampus and prefrontal cortex are in charge. They interact to create complex thoughts and rational behaviors. However, when we detect a threat in the environment, a different part of our brain takes control: the amygdala.
Our amygdala is a small, almond-shaped structure in our brain. It is like the fire alarm of our brain, it tells us when we are in danger. When we are in danger, our amygdala releases cortisol, which is the primary stress hormone. Cortisol increases our brain’s intake of its “fuel”, glucose, and suppresses other bodily functions that are not necessary in order to respond to the threatening situation. The amygdala signals to the brain to release other stress hormones as well.
This neural activity causes us to be alarmed and on edge, rendering us unfit for anything but returning to safety by any means possible. Fear-conditioned responses are theorized to be hardwired evolutionary adaptations that humans learned in order to survive back when we were escaping our natural predators. These decisions are made in the primitive part of the brain, not in the prefrontal cortex, which is considered to be an area of the brain that has been more fine-tuned with evolution. Older structures, like the amygdala, take control and cause us to react in a way that will most likely result in our survival.
This can usually cause us to respond in one of the following ways:
Many of us have heard of fight or flight before, but fawn and freeze are recognized less, causing survivors who responded in these ways to face additional victim-blaming. People falsely believe that they know how they will react in a distressing or threatening situation, but in reality, these responses are not conscious actions that we can control. Rather, they are hardwired decisions made by the part of our brain that is programmed to protect us from danger and ensure our survival.
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