People with Type A personalities typically exhibit aggressive behaviors and emotions such as competitiveness, impatience and anger. Although these attitudes have been generally accepted as characterizing Type A personality since its identification, About.com notes that experts do not know what this personality type fully encompasses.
In the mid-20th century, physicians Meyer Friedman and Ray Rosenman developed the idea of Type A personalities after studying patients with heart conditions. They designated it Type A Behavior Pattern and began conducting research into the risks accompanying it. Following their work, other researchers noticed a link between Type A Behavior Pattern and coronary heart disease. Other physical effects associated with TABP include muscle tension in the face, dark circles around the eyes, and high blood pressure.
TABP is regarded by most researchers as a learned behavior as opposed to inborn behavior. Environmental factors, such as culture and career, may incite TABP. High-stress work environments can aggravate individuals who are predisposed to impatience, leading to even more stress. The fight-or-flight response in people with Type A personalities can intensify and may provoke physically aggressive or violent acts, such as bullying. Their competitive and critical nature often deprives them of satisfaction in any achievements, and personal relationships can suffer as a result.