anxiety

Meaning: Anxiety is an emotional state of worry and apprehension about a possible future threat, with arousal such as faster heart rate, muscle tension and sympathetic nervous system activation. Fear is the response to an immediate, identifiable threat. Mild anxiety is normal and often adaptive. It is classed as an anxiety disorder when it is excessive, persistent and interferes with daily functioning. Main disorders: generalized anxiety disorder (chronic worry about many things), panic disorder (recurrent, unexpected panic attacks), specific phobia (intense fear of one object or situation), and social anxiety disorder (fear of scrutiny by others). The amygdala is the brain region most linked to fear and anxiety responses. In psychoanalytic theory, anxiety signals conflict among id, ego and superego and prompts defense mechanisms.

On the MCAT: A vignette describes symptoms, and you pick the disorder from the trigger and time course. A specific trigger points to a phobia. Months of diffuse worry with no single trigger point to generalized anxiety. Sudden, intense attacks that peak within minutes point to panic disorder. Passages may also explain phobias by classical conditioning and their persistence by avoidance. The Yerkes-Dodson idea, that moderate arousal gives the best performance on many tasks, may also appear.

Common confusion: Avoiding the feared object lowers anxiety, which is negative reinforcement. It strengthens the avoidance and is not punishment. Do not treat anxiety and fear as identical: fear has a present, specific threat.