The amygdala is a small-yet-crucial cluster of neurons located in the medial temporal lobe of the brain. The human brain actually has two of these clusters, the plural of which is called the amygdalae. However, the pair is commonly referred to as simply “the amygdala.” The amygdala is part of the body’s limbic system, and based on research that has been performed on the human brain, it is believed that its primary function is processing memory and emotion.
The Role of the Amygdala
The amygdala is largely responsible for processing memory and emotional responses, but its most basic responsibility is to act as the brain’s surveillance system. This means that it is constantly monitoring one’s surroundings for potential dangers and is ready to help initiate a fight-or-flight response.
The amygdala is also closely related to the ability to feel and apply empathy to certain situations. It helps aid people in making decisions by filtering the thoughts people have about themselves and the world around them. In this way, the amygdala plays a role in nearly every decision we make, no matter how urgent or trivial they may be.
Amygdala Sex Differences
The amygdala is one of the most well-understood regions of the brain with regard to differences between the sexes. Specifically, the amygdala is larger in male brains than in female brains for children between the ages of 7 and 11, adult humans and adult rats. This region of the brain also shrinks by as much as 30 percent in human males that are castrated.
The lateralization of the amygdalae may also be affected by a person’s sex. In one study that involved men and women watching horror films, enhanced memory of the film was related to greater activity in the left amygdala in women, while in men, the right amygdala was more active. The right amygdala is linked with taking action when confronted with negative emotions, while the left amygdala is more associated with memory retention. This may be why men are more likely to have a physical reaction to emotionally stressful stimuli.
The amygdala also appears to be linked to anxiety and the fact that women are more likely to be diagnosed with anxiety disorders than men. Men typically have higher levels of serotonin receptors in their amygdalae, which is why they are likely to have a stronger fight-or-flight response than women in stressful situations.
Disorders Associated With the Amygdala
A number of neurological and mental disorders may be closely related to abnormal functioning of the amygdala. These disorders include autism, depression, post-traumatic stress disorder and many phobias. As stated above, the amygdala may also be closely related to anxiety disorders, particularly in women. This can be due to a number of different factors ranging from brain damage to developmental disorders.
There is much that scientists have yet to discover about the brain, and that includes the function and nature of the amygdalae. Although this particular brain structure is better understood than most of the brain, there is still more that we can learn about it. What we do know is that it is fascinating and versatile. It is responsible for processing our emotions, and it helps us make every decision we make throughout our lives.
Neil Mortensen is a freelance writer who concentrates on anatomy, brain physiology, Brain Injuries, neuroscience, general science and other issues as well.