Anxiety refers to a sense of apprehension and fear often marked by physical symptoms (such as sweating, tension, and increased heart rate). Anxiety can express itself in various ways. trouble falling asleep; dwell on a particular situation and find it difficult to think of something else; feel tense, restless, jittery, dizzy and sweaty; have trouble concentrating; overeat or lose your appetite; be overly vigilant and startle easily; have a feeling of impending disaster, as if "something bad is going to happen;" or are depressed (anxiety can mask depression).
List of books: Anxiety
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anxiety refers to a mood state characterized by strong negative affect, bodily symptoms of tension, and apprehensive anticipation of future danger or misfortune.