Social Anxiety Disorder

Social anxiety disorder involves overwhelming anxiety and excessive self-consciousness in everyday social situations.
People with social anxiety have a persistent, intense and sometimes chronic fear of being watched and/or judged by other people and being embarrassed and/or humiliated by their actions. Their fear may be so severe that it interferes with work or school and other everyday activities.
Whilst many people with social anxiety recognize that their fear of being around people may be excessive and unreasonable, they are unable to minimize or overcome it. They often worry for days or weeks in advance of a dreaded situation.
Social anxiety disorder can be limited to only one type of situation - such as a fear of speaking in formal or informal situations, or eating, drinking, or writing in front of others, or, in its most severe form, may be so broad that a person experiences symptoms almost anytime they are around other people.
Social Anxiety Disorder can be very debilitating - it may even keep people from going to work or school on some days. Many people with social anxiety have a hard time making and keeping friends.

For the last 3 decades it has been considered that a chemical imbalance gives rise to many forms of social anxiety, but a new line of thinking is looking at the amygdala (a pair of small organs within the medial temporal lobes of the brain) being the actual cause.