Worry is a category of
perseverative cognition, i.e., a continuous thinking about negative events in the past or in the future. As an
emotion "worry" is experienced from
anxiety or concern about a real or imagined issue, often personal issues such as health or finances, or external broader issues such as environmental pollution, social structure or technological change. It is a natural response to anticipated future problems. Excessive worry is a primary diagnostic feature of
generalized anxiety disorder, but also is pervasive in other psychological disorders, like
schizophrenia. Most people experience short-lived periods of worry in their lives without incident; indeed, a mild amount of worrying has positive effects, if it prompts people to take precautions (e.g., fastening their
seat belt or buying insurance) or avoid
risky behaviors (e.g., angering dangerous animals, or
binge drinking), but with excessive worrisome people they overestimate future dangers in their assessments and in its extremities tend to
magnify the situation as a dead end which results in stress. Overestimation happens because analytic resources are a combination of external
locus of control, personal experience and belief fallacies. Chronically worried individuals are also more likely to lack confidence in their problem solving ability, perceive problems as threats, become easily frustrated when dealing with a problem, and are pessimistic about the outcome of problem-solving efforts. Seriously anxious people find it difficult to control their worry and typically experience symptoms like restlessness, fatigue, difficulty in concentrating, irritability, muscle tension and sleep disturbance. ==Theories==