The research – which was conducted by experts from University College London
(UCL) and the Anna Freud Centre
– also shows that children who grow up around family violence may be more prone to mental health problems in later life, especially anxiety and depression.
Representing UCL's Division of Psychology and Language Sciences, lead author Dr Eamon McCrory, spoke to the journal, Current Biology. He said
: "We are only now beginning to understand how child abuse influences functioning of the brain's emotional systems.”
"This research is important because it provides our first clues as to how regions in the child's brain may adapt to early experiences of abuse in the home.
"Enhanced reactivity to a biologically salient threat cue such as anger may represent an adaptive response for these children in the short term, helping keep them out of danger. However, it may also constitute an underlying neurobiological risk factor increasing their vulnerability to later mental health problems, and particularly anxiety.
"The next step for us is to try and understand how stable these changes are. Not every child exposed to family violence will go on to develop a mental health problem; many bounce back and lead successful lives. We want to know much more about those mechanisms that help some children become resilient."
Magnetic resonance imaging brain scans were conducted on 20 children from the London area, who had an average age of 12. All of the participants had been exposed to domestic violence and have since been referred to social services.
While the children were in the scanner, they were shown pictures of faces – both male and female – with sad, calm or angry expressions. Their patterns of brain activity were recorded and compared to those of 23 children with no history of domestic violence.
The angry faces had a distinct impact on the brains of children who had been exposed to domestic violence.
According to previous studies, similar patterns are shown in the brains of soldiers who are exposed to violence. They, as well as children who witness domestic violence, tune their brains to be hyper-aware of danger around them.