effect of childhood trauma on brain development
As recently as 25 years ago, it was still frequently believed that the structure of the brain had already been genetically determined at birth. Now, however, we of course know that this is absolutely NOT the case. Indeed, the experience, in early life, of trauma, abuse or neglect can have a profoundly adverse effect upon both the brain’s chemistry and its architecture (ie the way in which its physical structure develops).
The diagram below shows the human brain’s left and right hemispheres together with some of each hemisphere’s particular functions.
CLICK ON IMAGE TO ENLARGE
CLICK ON IMAGE TO ENLARGE
Studies on animals can help us to understand the effects of trauma on the developing human brain. For instance, if animals are subjected to inescapable stress they develop behaviours such as :
– abnormal alarm states
– acute sensitivity to stress
– problems relating to both learning and memory
– aggression
– withdrawal
The symptoms listed above are, in fact, very similar to those displayed in humans who are suffering from post-traumatic stress disorder (PTSD).
In both the cases of humans and of animals, investigations suggest that prolonged exposure to stress adversely affects a vital brain system ( the NORADRENERGIC BRAIN SYSTEM).
Indeed, in humans it has been found that even in adults (let alone children) just one exposure to severe trauma (eg a terrifying battle) can significantly alter an adult’s brain and lead to PTSD.
STUDIES ON EFFECTS OF CHILDHOOD TRAUMA ON BRAIN :
Drissen et al (2000) found that those who had suffered severe childhood trauma had smaller volumes of two vital brain structures which play a role in stress management; the two structures physically affected by trauma were :
1) THE AMYGDALA
2) THE HIPPOCAMPUS
On average, those who had experienced severe childhood trauma were found to have :
– amydallas which were 16% smaller than those who had not experienced significant trauma
– hippocampuses which were 8% smaller than those who had not experienced significant childhood trauma.
Further research by Shore (2001) has shown that the brain’s right hemisphere (see diagram of the brain’s right and left hemispheres above), which has deep connections into the limbic and autonomic nervous systems, is impaired in terms of its ability to regulate these systems properly; leading to profound difficulties managing stress in those who had suffered serious childhood trauma.
David Hosier BSc Hons; MSc; PGDE(FAHE)
