What are the consequences of amygdala removal

The amygdala refers to a cluster of neurons that is symmetrically distributed on the left and right sides of the inner temporal lobe of the brain, a bit like an almond. It is part of the basal ganglia, deep in the parahippocampal sulcus. This part of the tissue retains a structure that is similar to that of animals. International brain experts have found that the amygdala is the neural center for the establishment of fear memory and plays an important role in various human emotions.

What are the consequences of amygdala removal?

1. Psychopaths cannot judge other people's expressions.

British researchers have found that people with psychosis have difficulty interpreting facial expressions and detecting emotions from people's faces, especially fear or sadness. This may be due to damage or underdevelopment of a special part of the brain called the amygdala.

2. Mental patients have some violent or antisocial behavior

But people who usually have no remorse or guilt for these actions. Even young children may be diagnosed with psychopathic tendencies, but there is rarely an explanation for their unusual behavior.

3. Rarely feel guilty or regretful

The researchers say the findings suggest why these people have little sense of guilt or remorse, and lack sympathy for those who have been harmed. This research can be used to evaluate patients, determine the best treatment, and monitor how well treatment is working. In addition, patients whose amygdala was damaged due to stroke or virus also exhibited the same behavior and were unable to recognize specific facial expressions.

Although a damaged amygdala cannot guide the visual system to collect information, its ability to process visual signals is still intact. That is to say, in addition to analyzing eye signals, the amygdala will also tell you to pay attention to other people's eyes first.

4. Unable to recognize other people’s fearful expressions

The observations lasted for more than 20 years. It turned out that the reason she couldn't judge the facial expressions of fear in the photos was because she couldn't focus on the eyes of other people's faces. If she is reminded to watch the eyes of a fearful face, she will also be able to tell which one is frightened, but this ability is short-lived and requires constant reminders to maintain. Adelphi had the woman and other volunteers look through a small hole at photos of people with different facial expressions. Among them, the facial expressions of the people in some photos are afraid, while the facial expressions of the people in other photos are happy. The results showed that people with normal brains usually look directly at the "eyes", especially for "fearful faces"; however, this woman could not instinctively look at the eyes, but stared straight at the photos and finally judged that the facial expressions of everyone in the photos were "neutral". Remarkably, if the scientists reminded the woman to look into people's eyes, she was also able to tell which person was in fear.