Instrumental Aggression: Definition & Examples


  • Instrumental aggression is aggression used as a means to an end. This aggression does not necessarily need to be intended to cause pain.
  • Instrumental aggression can be physical or social.
  • Operant conditioning, genetics, the endocrine and nervous system, negative affect and mood, and environmental factors have all been proposed as explanations for instrumental aggression — and aggression in general.
  • Some conditions, such as psychopathy and the experience of pain, lead to high rates of instrumental aggression. Psychopathy, in particular, is associated with decreased emotional arousal and increased motivation by revenge and material gain in committing serious offenses such as homicide and sexual assault.
instrumental aggression
Instrumental aggression is goal-oriented and calculated behavior involving harming others as a means to an end. Unlike hostile aggression which is driven by anger, instrumental aggression is unemotional and used intentionally to achieve something the aggressor wants through intimidation or force.

What is Instrumental Aggression?

Instrumental aggression is a form of aggression where the primary aim is not to inflict pain on the victim but to reach some other goal where aggression is merely incidental.

Those who use instrumental aggression are motivated by achieving a goal and do not necessarily intend to cause pain (Berkowitz, 1993). For example, a hitman who murders for pay displays instrumental aggression.

Instrumental aggression can be both overt and covert. Evolutionary psychologists have historically believed that males use aggression to display dominance over other males in order to protect a mate and perpetuate the male’s genes.

Meanwhile, women often express themselves through communication that impairs the social standing of another person.


Many psychologists believe that instrumental aggression can be understood through Skinner’s theory of operant conditioning (Holland & Skinner, 1961).

Essentially, operant conditioning contends that the probability of a certain behavior — such as aggression — is increased by a prior history of reward or reinforcement in response to that behavior.

Similarly, psychologists believe that instrumental aggressive behavior is encouraged by the presence of stimuli that increase the expectation of a positive outcome from behavior.

To illustrate the role that operant conditioning can play in learning aggression, consider a child who uses force to take a toy that they want away from another child.

This child may feel happy after showing aggressive behavior because the toy is fun to play with. This positive reward makes it more likely that the child will participate in the toy-taking behavior in the future to get what they want.

Instrumental aggression is a means to an end. However, in the view of operant conditioning, the actual removal of the apparent reward for instrumental aggression may not immediately eliminate the behavior because the aggressor has built up an internal association between behavior and reward that leads to aggression.

Genetics and Endocrine/Nervous System Explanations

Scientists have attributed aggression to a panoply of biological, environmental, and psychological factors. Imbalances in certain hormones, such as testosterone and cortisol, as well as neurotransmitters, such as serotonin and dopamine, have been linked to aggression (Rosel & Siever, 2015).

Testosterone, in particular in high levels, has been shown to lead to greater levels of social dominance and physical aggression in adolescents, particularly in situations where physical aggression leads to social dominance (Tremblay, 1998).

These hormonal imbalances can be due to genetics as well as brain structure. For example, people who have a smaller amygdala than average tend to be more aggressive than others.

Matthies et al. (2012), for instance, found that participants with higher aggression scores, as measured through a written assessment, had a 16-18% reduction in amygdala volumes.

In addition, a similar study found that men with lower amygdala volume displayed higher levels of aggressive behavior and psychopathic features from childhood to adulthood (Pardini, Raine, Erickson, & Loeber, 2014).

Finally, those with an intermittent explosive disorder, which is characterized by reactive expressive behavior, have exaggerated amygdala reactivity in response to faces that express anger.

Another part of the brain that has been associated with aggressive behavior is the hypothalamus (Haller, 2013). However, the frontal cortex region of the brain can inhibit this aggression.

Environmental factors also play a role in aggressive behavior. Those who frequently witnessed aggression in childhood, such as those who underwent trauma, are more likely to display aggressive behavior in adulthood (Bevilacqua, Carli, & Sarchiapone et al., 2012).

Finally, several mental health conditions, such as ADHD, bipolar disorder, bipolar personality, narcissism, and PTSD, have been associated with an increased tendency to engage in aggressive behavior.

Aggressive tendencies can also be found in some patients with conditions such as epilepsy, substance use disorder, and brain injuries or abnormalities.

Negative Affect and Mood

Another possible cause of aggression is negative affect and mood. In one study, participants who placed their hand in the water while they were administered either a reward or punishment and were told they might experience pain reported greater discomfort.

Experienced greater levels of annoyance, anger, and irritation and behaved more punitively to the person who administered the reward or punishment than those who were not (Berkowitz & Thome, 1987).


Instrumental Aggression and Psychopathy

Psychopathy is a psychiatric disorder involving a noticed lack of guilt, remorse, and empathy (Glenn & Raine, 2009).

As well as lacking fear of the negative consequences of risky or criminal behavior and insensitivity to punishment, psychopaths are often described as superficially charming, glib, manipulative, conning, and grandiose (Glenn & Raine, 2009).

Psychopathy is associated with an increased risk for instrumental aggression, which distinguishes the condition from other antisocial disorders. This has implications for the crimes that those with psychopathy commit.

While psychopathic criminals are more likely to engage in predatory violence, non-psychopathic violent criminals are more likely to engage in reactive violence. This applies especially to serious offenses like sexual assault or homicide.

Meanwhile, psychopathic and non-psychopathic criminals tend to commit less serious offenses, such as theft and burglary, at similar rates (Glenn & Raine, 2009).

Researchers such as Williamson, Hare, and Wong (1987) have found that psychopathic offenders were more motivated by material gain or revenge than non-psychopathic offenders (45.2% vs. 14.6% of violent acts) (Glenn & Raine, 2009).

Furthermore, psychopathics were less likely to have been emotionally aroused during their crimes than non-psychopaths (2.4% vs. 31.7% of violent acts).

Indeed, 93.3% of homicides committed by psychopathic offenders were instrumental in nature, compared with 48% of those by non-psychopathic in nature.

This is to say that the reduced empathy, guilt, and remorse exhibited in psychopathy has been implicated in increased instrumental motives in committing violent crimes (Glenn & Raine, 2009).

Instrumental Aggression and Pain

Some researchers, such as Hartmann (1969), have argued that pain can influence instrumental aggression. In his study, Hartmann subjected adolescent delinquents to either anger-arousing or non-arousing experiences.

They then viewed a nonaggressive control film or one of two films depicting a fight sequence. The pain-cues film focused on the pain responses of the victim, while the instrumental aggression film highlighted the inflictor’s aggressive behavior.

The adolescents were then asked to participate in a learning task with a provocateur. When the provocateur made mistakes, the adolescents could administer shocks to the provocateur.

Hartmann found that, regardless of arousal level, participants who witnessed the modeled aggression behaved more punitively toward the provocateur than participants who had observed the same models behave non-aggressively.

Aroused viewers tended to respond more positively than non-aroused viewers did, and angered participants who witnessed modeled pain reactions tended to respond more positively than observers who were exposed to model instrumental aggression (Hartmann, 1969).

Types of aggression

There are three main types of aggression: instrumental, hostile, and relational aggression.

Hostile or physical aggression occurs when a person intends to harm another by carrying out a physical behavior — such as hitting, shooting, kicking, or stabbing — or by threatening to do so.

Meanwhile, relational aggression occurs when someone makes efforts to damage another’s relationships through actions such as spreading rumors, name-calling,  or social exclusion.

Hostile vs. Instrumental Aggression

One of the biggest distinctions in the field of aggression is between hostile and instrumental aggression.

When someone engages in hostile aggression, they are impulsive, emotionally driven, and reactive. Meanwhile, instrumental aggression is proactive, premeditated, and cold-blooded.

The goal of instrumental aggression is to obtain a preferred outcome or to coerce others and is founded in the social learning model of aggressive behavior in which aggression is learned through vicarious reinforcement and maintained because the perpetrator expects that the behavior will result in a reward.

Instrumental aggression is often associated with traits such as lack of guilt and empathy and can be either physical or relational.

Meanwhile, hostile aggression is often reactive and is not associated with a lack of guilt and empathy (Glenn & Raine, 2009).

Often, those who commit hostile aggression do so due to emotional arousal rather than revenge or material or social gain.


Berkowitz, L., & Thome, P. R. (1987). Pain expectation, negative affect, and angry aggression. Motivation and emotion, 11(2), 183-193.

Berkowitz, L. (1993). Aggression: Its causes, consequences, and control. Mcgraw-Hill Book Company.

Bevilacqua, L., Carli, V., Sarchiapone, M., George, D. K., Goldman, D., Roy, A., & Enoch, M. A. (2012). Interaction between FKBP5 and childhood trauma and risk of aggressive behavior. Archives of general psychiatry, 69(1), 62-70.

Glenn, A. L., & Raine, A. (2009). Psychopathy and instrumental aggression: Evolutionary, neurobiological, and legal perspectives. International journal of law and psychiatry, 32(4), 253-258.

Gradinger, P., Strohmeier, D., & Spiel, C. (2009). Traditional bullying and cyberbullying: Identification of risk groups for adjustment problems. Zeitschrift für Psychologie/Journal of Psychology, 217(4), 205-213.

Haller, J. (2013). The neurobiology of abnormal manifestations of aggression—a review of hypothalamic mechanisms in cats, rodents, and humans. Brain research bulletin, 93, 97-109.

Hartmann, D. P. (1969). Influence of symbolically modeled instrumental aggression and pain cues on aggressive behavior. Journal of Personality and Social Psychology, 11(3), 280.

Holland, J. G., & Skinner, B. F. (1961). The analysis of behavior: A program for self-instruction.

Matthies, S., Rüsch, N., Weber, M., Lieb, K., Philipsen, A., Tuescher, O., … & van Elst, L. T. (2012). Small amygdala–high aggression? The role of the amygdala in modulating aggression in healthy subjects. The World Journal of Biological Psychiatry, 13(1), 75-81.

Pardini, D. A., Raine, A., Erickson, K., & Loeber, R. (2014). Lower amygdala volume in men is associated with childhood aggression, early psychopathic traits, and future violence. Biological psychiatry, 75(1), 73-80

Rosell, D. R., & Siever, L. J. (2015). The neurobiology of aggression and violence. CNS spectrums, 20(3), 254-279.

Tremblay, R. E. (1998). Testosterone, physical aggression, dominance, and physical development in early adolescence. International Journal of Behavioral Development, 22(4), 753-777.

Williamson, S., Hare, R. D., & Wong, S. (1987). Violence: Criminal psychopaths and their victims. Canadian Journal of Behavioural Science/Revue canadienne des sciences du comportement, 19(4), 454.

Saul Mcleod, PhD

BSc (Hons) Psychology, MRes, PhD, University of Manchester

Educator, Researcher

Saul Mcleod, Ph.D., is a qualified psychology teacher with over 18 years experience of working in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.

Charlotte Nickerson

Research Assistant at Harvard University

Undergraduate at Harvard University

Charlotte Nickerson is a student at Harvard University obsessed with the intersection of mental health, productivity, and design.