What Factors Lead to Aggression?

A woman showing physical aggression
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In psychology, the term aggression refers to a range of behaviors that can result in both physical and psychological harm to oneself, others, or objects in the environment. This type of social interaction centers on harming another person either physically or mentally.

Forms of Aggression

Aggression can take a variety of forms, including:

  • Physical
  • Verbal
  • Mental
  • Emotional

While we often think of aggression as purely in physical forms such as hitting or pushing, psychological aggression can also be very damaging.

Intimidating or verbally berating another person, for example, are examples of verbal, mental, and emotional aggression.

Purposes of Aggression

Aggression can also serve a number of different purposes:

  • To express anger or hostility
  • To assert dominance
  • To intimidate or threaten
  • To achieve a goal
  • To express possession
  • A response to fear
  • A reaction to pain
  • To compete with others

Types of Aggression

Psychologists also distinguish between two different types of aggression:

1. Impulsive Aggression

Impulsive aggression, also known as affective aggression, is characterized by strong emotions, usually anger. This form of aggression is not planned and often takes place in the heat of the moment. When another car cuts you off in traffic and you begin yelling and berating the other driver, you are experiencing impulsive aggression.

2. Instrumental Aggression

Instrumental aggression, also known as predatory aggression, is marked by behaviors that are intended to achieve a larger goal.

Instrumental aggression is often carefully planned and usually exists as a means to an end. Hurting another person in a robbery or car-jacking is an example of this type of aggression. The aggressors goal is to obtain money or a vehicle, and harming another individual is the means to achieve that aim.

Factors Than Can Influence Aggression

Researchers have suggested that individuals who engage in affective aggression, defined as aggression that is unplanned and uncontrolled, tend to have lower IQs than people who display predatory aggression. Predatory aggression is defined as aggression that is controlled, planned, and goal-oriented.

A number of different factors can influence the expression of aggression. Biological factors can play a role. Men are more likely than women to engage in physical aggression. While researchers have found that women are less likely to engage in physical aggression, they also suggest that women do use non-physical forms, such as verbal aggression, relational aggression, and social rejection.

Environmental factors also play a role, including how people were raised. People who grow up witnessing more forms of aggression are more likely to believe that such violence and hostility are socially acceptable. Bandura's famous Bobo doll experiment demonstrated that observation can also play a role in how aggression is learned. Children who watched a video clip where an adult model behaved aggressively toward a Bobo doll were more likely to imitate those actions when given the opportunity.


Behar, D.; Hunt, J.; Ricciuti, A.; Stoff, D.; Vitiello, B. (1990). Subtyping Aggression in Children and Adolescents. The Journal of Neuropsychiatry and Clinical Neurosciences 2 (2): 189–192.

Berkowitz, L. (1993). Aggression: Its causes, consequences, and control. New York, NY: McGraw-Hill.