The Encyclopedia on Early Childhood Development, produced by the Centre of Excellence for Early Childhood Development (CEECD) and the Strategic Knowledge Cluster on Early Child Development (SKC-ECD), is a free, comprehensive, and easy-to-use resource providing knowledge devoted to early childhood development. The Encyclopedia links parents, educators and community service providers with the most up-to-date knowledge from the field for children ages 0 to five. You can follow the Encyclopedia on Twitter @Encyclo05. The YouTube Encyclopedia Channel offers the following short videos on early childhood development:

• Aggression
• Anxiety and Depression
• Emotions
• Hyperactivity and inattention (ADHD)
• Peer Relations

The Encyclopedia YouTube Channels are available in French, Spanish and Portuguese.

The current featured topic is “temperament”, with articles, fact sheets and a video on What To Do When Children Bite. The video stresses that “It’s normal for young children to hit and bite. As their brain develops and their motor ability increases, children will naturally express anger and aggression through such behaviours”, and gives strategies for parents in preventing and dealing with early childhood aggression.

The video shows children in a childcare setting and demonstrates staff intervention and skill building with the children. A supporting document to the video, produced under topic editor Richard E. Tremblay, PhD, Université de Montréal, Canada and University College Dublin, Ireland, goes into much greater detail. It starts by noting that “Most parents of first born are shocked and understandably worried when they see their infant child attempt to hit them when angry. Very few parents expecting their first child know that beautiful young babies express anger with hits and kicks long before they learn to walk. The frequency of physical aggressions increases with age over the first three to four years after birth. Physical aggression is the leading problem in childcare centres and the leading reason why preschool children with behaviour problems are referred for clinical help. ”

The article points out that physical aggression most commonly starts between 1-2 years of age as a response to frustration and as a means to reach a goal. For most children it peaks between 30 to 42 months of age and then declines as children develop the ability to regulate their attention and emotions, control their impulses and use verbal communication. In 5%-10% of children, more often boys, frequent use of physical aggression continues; these children are at increased risk of chronic aggression in late childhood, adolescence and adulthood. Studies show that chronic physical aggression is associated with other social risk factors for young children, including low income, young parents and parental substance use issues. For those children whose resort to physically aggressive behavior does not follow the normal arc of decline, “the consequences of aggressive acts become more serious with age as children become stronger and are less supervised.”

Sex differences in frequency and level of physical aggression have been consistently reported. “Even though most children show a decrease in the frequency of physical aggression as they grow up, girls tend to reduce their aggression earlier, and the sex differences tend to stay stable through childhood and adolescence.”

The article points out that: “As physical aggression declines, face-to-face verbal aggression increases, followed by social and relational aggression around 4-5 years of age. The goal of relational aggression is to harm a person’s social relationships and self-esteem, for example by becoming friend with someone else in revenge. It includes non-verbal behaviours such as disdainful facial expressions and direct expressions of rejection. These forms of aggression are slightly more common in girls but are also used by boys, sometimes in conjunction with direct verbal and physical aggression. Both physically and relationally aggressive children tend to lack empathy and attribute hostile intentions to others, but perpetrators of relational aggression are likely to have advanced language skills, contrary to physically aggressive children. Indirect forms of aggression may cause as much pain in victims as physical aggression but perpetrators are less likely to face disapproval by adults and peers. A better understanding of the development of aggressive behaviours should help to establish effective prevention programs.”

The recommendation is for early intervention to contain aggressive behavior and teach appropriate interaction skills to young children. “Targeted programs combining parent and child intervention in the preschool years have resulted in improved parenting and decrease in children’s negative behavior…. Prenatal to toddlerhood home visits to support at risk families have been shown to reduce later behavior problems. Universal programs in preschool can improve children’s emotion regulation and reduce later aggression. A multi-modal intervention for aggressive boys in kindergarten was shown to improve high-school graduation and reduce criminality 15 years later.”

The article states, “warm, positive parenting can help reduce behavior problems but the effect of parental behavior is facilitated by children’s effortful control. Interventions can address children’s problem-solving strategies, support gentle parental discipline, and foster supportive teaching.”

An interesting development has been the study in other mammals of the value of rough-and-tumble play, which demonstrate that such play is critical for the development of the brain area responsible for executive control. “One consequence of lacking the opportunity to play…is misreading social signals that could prevent an encounter from escalating into aggression. Human children who engage in rough-and-tumble play show better social skills and play with peer is facilitated by a positive previous experience of playing with parents.”

The article points out that, “Regarding indirect aggression, it should be recognized that social and relational aggression are seriously harmful behaviours perpetrated by both boys and girls. Intervention could start in preschool and preferably involve parents and teachers. The goals would be to teach how to deal with relational aggression, as well as strategies for relationship building and problem solving.”

“Whatever the strategy, several keys to successful intervention targeting aggression in preschool children are proposed”:

1. Intervention should include parents;
2. Intervention must be flexible yet faithful to protocol;
3. Parental intervention should address both parenting behaviour and parents’ knowledge of child development;
4. Schools/centres should plan strategies to engage parents in intervention; needs for staff training must be realistically assessed.”