Harsh parenting could lead to smaller brains in adolescence, new study finds

Photo: Getty Images
Photo: Getty Images 

It's been widely reported that serious physical and emotional abuse can lead to impaired brain development in children, but a new study has found that even some parenting practices that might seem socially acceptable can have a serious and permanent effect.

A new study from Université de Montréal and the CHU Sainte Justine Research Centre, in partnership with researchers from Stanford University, has linked behaviour such as repeatedly getting angry, hitting, shaking or yelling at children with smaller brain structures in adolescence.

"The implications go beyond changes in the brain," said Sabrina Suffren, PhD, the study's lead author. "I think what's important is for parents and society to understand that the frequent use of harsh parenting practices can harm a child's development."

"We're talking about their social and emotional development, as well as their brain development."

The study found that the same brain regions were affected, whether the child had suffered from serious abuse or "harsh" parenting. 

"These findings are both significant and new," said Suffen. "It's the first time that harsh parenting practices that fall short of serious abuse have been linked to decreased brain structure size, similar to what we see in victims of serious acts of abuse."

Child development researcher and author Kari Sutton says this type of harsh parenting can come out when the parent is having strong feelings themselves. 

"The types of parenting practices that I would consider harsh are frequent and repeated yelling, negative comments, name calling, physical threats, aggression, and parents hitting children when they are very angry and emotionally out of control," she says.

"These parenting practices are frequently a sign of over-reactive, emotionally negative, coercive, controlling and authoritarian parenting styles."


Sutton says the implications for children are significant, because changes to the amygdala and pre-frontal cortex can affect emotional and behavioural regulation.

In the short-term, impacts of these structural brain changes can lead to children to display disruptive, aggressive, defiant, or anti-social behaviours, increased impulsivity, and less ability to control or regulate their behaviour," she says.

"They are also at higher risk of being involved in bullying – both as perpetrators and as victims.

"In the long-term, these structural brain changes have substantial influence on behavioural development throughout life and can also play a key role in the emergence of anxiety and depression and can also lead to substance abuse."

So should parents be worried about an occasional emotional outburst? Sutton says it's important to see the big picture.

"The key factor here for me is the word 'repeatedly'," she says. "These are not once-off occurrences (although shaking infants is never ever an acceptable thing to do as it can cause irreparable brain damage).

"This study focused on children who were constantly subjected to repetitive harsh parenting practices, not once off infrequent occurrences of anger.

"We all experience anger and frustration with our children at different times that's simply part of being human, it's how we deal with those emotions in the moment that count."

Sutton says it's important that if we do lose our temper, we apologise and repair the relationship, adding that the sort of parenting that is nurturing and helpful to our children's development includes:   

  • being warm, empathic, attuned and nurturing
  • listening to our children
  • allowing autonomy and encouraging independence
  • reasoning with children instead of demanding blind obedience
  • setting clear limits on behaviour
  • consistently enforcing boundaries
  • using positive discipline instead of punitive, forceful measures.

And if you recognise your own parenting in that list of "harsh", potentially damaging behaviour, Sutton says you've already taken the first step, and the next thing to do is to recognise where you can do things differently.

"Once they recognise that they need to change their parenting style – they need to choose one behavioural response they'd like to change (for example, to stop shaming or name calling) and work at changing this behaviour.

"They can also seek help from a psychologist or other parenting professional who can help them address the issues."