Social Psychology/Crowd behaviors

Aggregate action
Collective behavior is any instance of a large collective (either group or aggregate) engaging in some action. Of special attention are the behaviors of Social movements and Aggregate behaviors, which shed some light into the fundamental questions of what causes, maintains, and structures a society. One sort of such behavior is herd behavior. J-curve theory predicts social revolutionary change to occur when an intolerable gap develops between people's expected satisfaction of needs and their actual satisfaction of needs.
Self in social context (social structure, population density). Examines the influence of personal factors (personality, health, alienation, status, and values) on one's position in various kinds of group structures.
Dissent, Deviance and reactions to deviance. Examines the role of habitual mindsets and social functions on the existence of norms, as well as the impact of labeling and social controls on deviance. Deviance is always relative to norms, which are revealed via breaching experiments.
This field has aroused many explanations. Anomie theory considers some deviance to be a result of persons trying to achieve a cultural goal but lacking the appropriate resources or means to do so. Strain theory (sociology) explains deviance in terms of social strain. Differential association theory understands deviance to occur when the definitions and meanings that support deviant acts are learned. Control theory (sociology) explains deviant behavior as a product of being influenced by other persons. Labeling theory believes that the reaction that people have to rule violations can have a compelling effect on deviants, either in reinforcing or discouraging it. Finally, the routine activities perspective considers how deviance occurs out of the routines of everyday life.