What is the amygdala?
The amygdala is a part of the limbic system. It’s located at the end of the hippocampus. The amygdala is in charge of our response and memory of emotions, especially fear. It decides what memories to store and where to store those memories in the brain. The decision is made based on the intensity of emotional impact that a particular event evokes.
Why is fear important?
Fear is an indispensable part of human beings. It helps us keep ourselves safe from danger. Fear and related emotions heighten our awareness, which is likely controlled by the amygdala.
The amygdala plays an important roles in autonomic responses associated with fear and hormonal secretions.
Repeated exposure to fearful experiences teaches us to fear. This is known as fear conditioning – an associative learning process. As we encounter those experiences, the brain circuits change and form new memories. For example, an unpleasant sound will trigger the amygdala to leave a strong imprint on our perception of the sound. The enhanced perception is considered as distressing, leading to the formation of bad memories in which the particular sound is associated with unpleasantness. If we are startled by the noise, our automatic flight or fight response is triggered.
This response can be broken down as following:
- The sympathetic division of the peripheral nervous systen is activated.
- Heart rate and metabolic rates increase; pupils dilates.
- More blood flows to the muscles.
All of these are controlled by the amygdala, allowing us the respond properly to danger.
What happens when the amygdala is removed?
As the amygdala has such an important role in the survival of the human race, one is likely to wonder what would happen if the amygdala is removed. To find the answer for this question, scientists have used a procedure in which a thin wire is placed into the brain to remove the amygdala of rats. After this procedure, it’s reported that the rats lost their ability to fear. They didn’t seem to be afraid of anything, even cats. It’s possible that losing the amygdala has made rats forget the memories of fear, thus turning them into fearless creatures.
What if something goes wrong with the amygdala?
Fear and anxiety disorder has been associated with hyperactivity of the amygdala or amygdala abnormality. The body responds to danger with fear. As we perceive something as dangerous, we respond with anxiety.
Anxiety may result in panic attacks in which the amygdala perceives a situation as dangerous even when there’s actually no real threat. Problems with the amygdala can lead to many anxiety disorders such as Obsessive Compulsive Disorder (OCD), Post-Traumatic Stress Disorder (PTSD), Borderline Personality Disorder (BPD), and social anxiety disorder.
Hello Health Group does not provide medical advice, diagnosis or treatment.
Review Date: October 10, 2017 | Last Modified: September 11, 2019