The impact of trauma on the developing brain

Now that we have a better understanding of the brains development, we can look at recognising and distinguishing the impact of trauma.  Children and young people are very vulnerable to the effects of trauma because of their brain’s developmental immaturity.  Because a child’s brain is so malleable, the impact of trauma is faster to manifest.  It also leaves deeper tracks of damage.  Children’s development can slow down or be impaired following trauma. 

What particularly influences what will be seen in how trauma manifests later in life is when it occurred during brain development, i.e. what age and which part of the brain is developing at that time.

Here are some ideas on the influence of trauma experienced during the development of various parts of the brain.

Brain Stem

  • We may see an infant born with a faster heart rate who is very hard to soothe, won’t settle so readily and will find sucking difficult
  • This in turn will impact on development of attachment relationships 


  • The child is less likely to have relationships that will support the repetitive experiences required for physical and motor development

Limbic System (Amygdala/Hippocampus)

  • An impaired amygdala response in children means that they find it difficult to recognise the emotions that others are attempting to express in their face or their voice
  • The hippocampus and the amygdala combine together to generalise fear responses to the context in which the original fear response was generated e.g. children will not only respond to being yelled at directly, but may also respond to all yelling in their proximity
  • Limbic Kindling refers to the idea that avoidance will tend to make someone more avoidant.  The limbic system learns that when avoiding specific triggers reduces arousal and increases survival, avoidance as a general strategy works and therefore becomes more generalised.


  • In a moment of trauma an individual will find that the cortex is temporarily unavailable to them 
  • Their survival responses will come from the Limbic System and as such they may not be able to draw on language to explain why they did something (left hemisphere is inaccessible) or show logic, reasoning or sound judgment


  • The implications of lateral brain development depends on when the trauma is experienced 
  • The impact will be different as a result of which hemisphere is more active in its development at the time
Further Resources