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Anger and Aggression | Print |  E-mail
Behaviour and Mental Health Problems

Anger is a normal human experience, one of the emotions that fuels aggression.

Some people get angry when they do not get what they want, or when someone disagrees with them, or they think someone has insulted or threatened them.  Aggression, either physically or verbally expressed, is often an overreaction to the seriousness of the threat intended.  Adults may yell and swear, or may even engage in physical assaults as a way of expressing their anger. 

Despite popular opinion to the contrary, “venting” anger does not lead to reduced levels of aggression – it may, in fact, increase it.  People who consistently lose their temper and act out aggressively did not learn earlier in life how to control their emotions.  The key is not so much what causes aggression but what fails to curb it over time.

When aggression is frequent, severe, does not respond to usual methods of discipline, is of long duration, and has an impact at school, at home, in the community and with peers, it is a serious problem that needs to be addressed.

It is a myth that older children and teenagers are more likely to exhibit aggression.  In fact, toddlers are more naturally aggressive than any other group.  By 17 months most toddlers are physically aggressive towards other children and adults.  So, the onset of aggression is in toddlerhood, not in primary school.

Toddlers will tantrum if they don’t get what they want, usually because it may be their only means of expressing their feelings.  While this is normal behaviour for very young children, it becomes less so as the child ages. 

As children progress through the preschool years, most manage to curb their aggression by using their language skills, learning to calm and Very cheap viagra control themselves, and developing their problem-solving abilities as an alternative to hitting and lashing out. Children who lack these skills are at high risk for persistent social problems.  Some preliminary research has shown that there may be a relationship between delayed language development and physical aggression.  It may be that this is one risk factor that could be the buy amoxil online subject of early intervention.

One long-term study showed that about 14% of children followed over time had high early levels of aggression that increased as they got older, putting them at risk for poor outcomes in adult life.  For this group, several risk factors predicted their aggression:  having a younger sibling; having a mother with high levels of antisocial behaviour during high school; having a young mother; coming from a low-income family; and having a mother who smoked during pregnancy.  However, the best predictor of this life course was coercive parenting and family dysfunction during early childhood.

Another study found that kindergarten boys who showed high levels of oppositional behaviour and hyperactivity went on to develop chronic physical aggression, that caused them to be at higher risk of assaulting others or causing injury to themselves.  They also had a higher risk of school failure, of adult unemployment, of engaging in spousal or child abuse, of substance abuse, of depression, and of suicide.


Tremblay RE. Prevention of injury by early socialization of aggressive behavior.
Injury Prevention. 2002; 8 (Suppl. 4): IV17-21.

Dionne G, Tremblay RE, Boivin M, Laplante D, Perusse D. Physical aggression and expressive vocabulary in 19-month-old twins. Developmental Psychology. 2003; 39(2): 261-273.

Tremblay RE,  Nagin D, Seguin JR, Zoccolillo M, Zelazo PD, Boivin M, Perusse D, Japel C.  Physical aggression during early childhood: Trajectories and predictors. Pediatrics. 2004; 114(1): e43-e50.

Nagin DS, Tremblay RE. Parental and Online order prescription viagra early childhood predictors of persistent physical aggression in boys from kindergarten to high school. Archives of General Psychiatry. 2001; 58: 389-394.


In this section, you will learn what works and what doesn't work in the treatment of anger and aggression in children and adolescents, according to the very best research available.

Click here to read our “plain language” summaries of the latest research studies on the topic.


The following books and resources were developed by the Family Resource Centre at McMaster Children's Hospital based on recommendations from parents and the experiences of staff.

The selection of a book or resource is not an endorsement of all the information or suggestions contained in that resource.

Many of the resources are general in nature, and may not apply to your situation. Your health care professional is the best source of information about your child's health and concerns.

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Last Updated on Monday, 22 February 2010 15:07