Which neural substrates (components) of the brain are involved with the emotions of fear and anxiety?

Amygdala is involved in the process of emotions such as fear and anxiety.

Explanation:

The amygdala is an Almond-shaped structure present in the mid of the brain. It stores the memories of evil situations once experienced by the person. A part of the amygdala senses the outer environment clearly and compares it with the previous memories stored in it. When it finds any correlation of memory with the outside situation, it immediately reacts by sending flight responses. These flight responses given by the amygdala from the brain stimulates the emotions of fear and anxiety in humans. The role of the amygdala is to control fear and anxiety and manage these emotions effectively. But, in some cases, this may react in situations that are not evil for very sensitive people.