Stress and the Developing Brain
Dr. Johana “Jody” Kashiwa Brakeley is board certified in the pediatric subspecialty known as Developmental–Behavioral Pediatrics (DBPeds). Prior to specializing, she spent 25 years as a primary care pediatrician in Middlebury, Vermont. Dr. Brakeley currently has a private solo practice and is also a staff physician at the Child Development Clinic in Burlington. Her special interests are attention regulation issues (such as attention deficit hyperactivity disorder [ADHD]), autism spectrum disorders, behavioral challenges, temperament, executive skills, and general aspects of brain development. Her work focuses on children and families in which there are various differences in development and learning. She has a keen interest in collaborating with local and state partners to develop cohesive community systems of care that improve the lives of children and families.
Stress and the Developing Brain
"Stress" is receiving a lot of attention recently, and rightly so. Research shows that children who do not have the benefit of stable, responsive, nurturing relationships with consistent, protective, interactive adults can have differences in their brain development. Why? Because a supportive relationship with a trusted adult provides an important buffer against stress.
In the short term, children who experience stress without a buffering relationship can face delays in language, social-emotional development, and thinking skills.
Long term observations show that exposure to a prolonged, exaggerated stress response—without a buffering relationship—is associated with chronic physical and mental health conditions long into adulthood.
Three Kinds of Stress
Not all stress is "bad" stress. Harvard's Center on the Developing Child distinguishes between three kinds of responses to stress: positive, tolerable, and toxic.
These three terms do not refer to the stressful event or experience itself, but rather to how the experience affects the individual's stress response system. (Graphics below courtesy of Harvard.)
A Positive stress response is a normal and important part of healthy development.
For example, when a toddler falls down, he looks at his parent as though to ask, "Am I okay?" The parent assesses the situation and, if appropriate, smiles at the child to assure him that, "You are fine; you are safe." The child feels comforted (trusting that his parent is always protecting him), gets up and goes along his way.
As he falls, the child may have a brief increase in heart rate and mild elevation in stress hormone levels (e.g. cortisol). When the child has a responsive, interactive, caring adult to provide appropriate feedback, his stress response is calmed. The next time he falls, the child can use this experience as a guide.
Other situations that may trigger a positive stress response are the first day with a new caregiver, or having an immunization.
Remember, the way a child develops independence, confidence, and resilience is by hundreds of these small, daily, positive stress responses. Think of a tree growing in an open field. It's exposed to fierce winds, storms, heavy rain and drought. In response, the tree develops a deep root system and a strong, solid trunk. It will become sturdy, durable, and healthy.
A Tolerable stress response occurs when the stressful experience is more severe and lasts longer.
Examples are the serious illness or death of a loved one, floods, fires, hurricanes, typhoons and other natural disasters.
In these situations the stress response is stronger. Heart rate, blood pressure, and breathing rate are all increased and last longer. Pupils dilate and one may experience stomach cramps, chest pain or trouble breathing.
When there is a caring, protective adult to "buffer" this experience and it is not overly prolonged, the child can adapt and the brain and other organs recover from what might otherwise be damaging effects.
A Toxic stress response can occur when a child experiences strong, frequent, and/or prolonged adversity—without the support of at least one relationship with a caring, trusted adult.
Examples of extreme adversity are physical or emotional abuse, chronic neglect, caregiver substance abuse or mental illness, exposure to violence, and/or the accumulated burdens of family economic hardship.
Research indicates that a child only needs one trusted adult (the more the better) to provide an emotional buffer against such difficult circumstances—but that one person is essential.
Without a buffering relationship, the prolonged activation of the stress response system can disrupt the development of brain architecture and other organ systems, and increase the risk for stress-related disease and cognitive impairment well into the adult years, such as:
- high blood pressure
- some forms of cancer
- substance abuse, etc.
(Graphic courtesy of the Sydney Morning Herald)
Protect the Early Years
We know that very young children form one million new brain cell connections every second when they have healthy and reliable relationships with the adults in their environment. It is essential that we spread the knowledge that our children's success is built from the bottom up, with a strong mental foundation for learning, skill-building and social-emotional development.
Investing more deeply in these aspects of early childhood is a "no brainer."