Topic 1.5 ACES and their Impact on Brain Functioning

Research shows many ways ACES exposure changes children’s brain development and functioning. 

Three shots of a brain model. Source: Brain from

When people experience stress, their bodies release chemicals and hormones.

Experiencing stress again and again causes the body to release the chemicals/hormones all the time.

When this happens during a developmental period the body learns to behave like they are experiencing stress all the time.

Over time releasing the chemicals and hormones change how the body’s genes work.

The body stops behaving the way it does for most people and starts behaving differently.

When children experience ACES, the genes that help the body learn to handle stress change:

  • When a child’s body is acting like it is in danger, the child is more likely to over-react.
  • The body starts to think the person is always in danger.
  • The person acts like they are in danger (even when they aren’t).
  • When the child over-reacts in a classroom, that looks like challenging behavior.

Consider Zane

His family recently immigrated from El Salvador, which has been experiencing civil war for decades. Zane’s father, three uncles and a brother have all been killed. Several of these murders happened while Zane was watching.  You find that Zane has a lot of issues with trust, and often acts out when he feels threatened. At nap, Zane tends to wet his pants, which leads to embarrassment and acting out.

When the body reacts to stress again and again, the person has an increased risk for cancer, heart disease, depression, and more. 

When a child is exposed to ACES over and over again for a long time, it can impact the brain.

The release of chemicals and hormones changes the size and shape of different parts of the brain including:

  • The hippocampus, which helps balance emotions, stores memories and manages stress. 
  • The prefrontal cortex, which is responsible for decision-making and impulse control. 
  • The amygdala, which is associated with the ability to process fear.
  • Brain cells – some brain cells will get swollen or inflamed and some will age faster.

Children experiencing ACES are at-risk for over-reacting to stress when they are adults.

A woman stares in distress. Source: Stressed from

The brain doesn’t develop new connections in the same way as people who have not expereinced ACES.       

Children experiencing ACES have a harder time building brain connections through everyday learning, play, and other life functions. 

Children experiencing ACES have a more difficult time:

  • With memory,
  • Understanding new information,
  • Deciding what is important,
  • Deciding what can be ignored, and
  • Deciding what steps to take when dealing with tasks and information.

When these parts of the brain changes, it may never recover.