Chapter 3 : Brain Development

Overview

A baby is eating breakfast and drops their spoon off the high chair tray. The adult nearby picks it up and places it back on the tray with a smile and kind word. The baby looks at the adult and then the spoon, picks it up and drops it onto the floor again. The adult laughs and picks the spoon up, replacing it on the tray as they gently smooth down the baby’s hair. This interaction happens three more times. The adult recognizes the child’s need for repetition of this cause and effect activity and gladly participates in the back and forth game. After all, it is a game that is building a healthy brain.

A clear understanding of brain development helps adults support healthy brain growth in the children they live and work with. Studying the brain gives us a better understanding of children’s development, differing abilities, and guides us in improving programs and policies impacting children and families.

This chapter will cover current information on how the brain develops and what is required to keep it healthy. It will explore functions of brain regions in a typically developing brain and the impact of trauma and stress. Finally, it will address applications of brain development to the field of Early Childhood. The science of brain development is constantly changing, and teachers should strive to stay abreast of current research by visiting reliable websites such as the Center on the Developing Child at Harvard University or the Institute for Learning and Brain Sciences at University of Washington.

 

3.1 Brain Development Basics

3.1.1 Introduction

The brain is the most complex organ in the human body, and the only organ to study itself. It is critical to understand how the brain develops and what is necessary to maintain its health because it informs and impacts everything we do in our lives, especially when working with children. As we will learn, the brain develops quickly in the early childhood years and continues to change throughout our lives.

 

When we understand the brain, we understand the power and impact of positive early childhood experiences. We also come to understand the impact on young brains from toxic stress and trauma and how we can prevent this. Building healthy brains from the start benefits everyone.

3.1.2 Brain Anatomy

At the cellular level, the brain is made up of 86 billion nerve cells called neurons . There are at least 10 times more support cells, called glial cells . Neurons communicate with each other through billions of connections in an electrochemical process. There are about 500 trillion connections in the adult human brain.

Although there has long been a debate about whether we are more impacted by nurture (our environment) or nature (our individual biology), we now understand that it is actually a unique combination of both. Neither nature nor nurture fully explains what makes us human; it is a complex relationship between the two. Biology and genetics provide the potential, but our social environment shapes our ability to access that potential.

 

3.1.2.1 Neurons

At the most basic level, a neuron is made up of a dendrite, cell body and axon. Between neurons there is a small gap called the synaptic gap.

A dendrite and its spines receive information from other neurons. The number of dendrites on a neuron varies from a few hundred to thousands. Dendrites are covered with spines (varicosities) that are neurotransmitter receptor sites.

The cell body and its DNA genetic system use the nutrients that the blood brings to maintain the cell and to synthesize neurotransmitter molecules (messengers between cells).

The axon sends information from the neuron to other neurons. Each neuron generally has one axon branching out into many terminals. Axons vary in length from 1 millimeter to about 3 feet! Mature axons are covered in an insulated coating, which looks like sausage links, called myelin.

The synaptic gap is the tiny space between neurons; the neurons don’t actually touch. Neurotransmitters are released into the gap and act as chemical messengers to the receiving neuron.

Neurons transmit information to each other through axons and dendrites by using the synaptic gap to exchange neurotransmitters. The axon sends a message through a series of electrical impulses called the action potential. When the impulse reaches the end of the axon the electrical activity ceases. A chemical process takes place in the form of neurotransmission. If the message is “transmit information” an electrical charge is triggered in the next neuron. That neuron’s dendrite receives the message and electrically sends it through the axon to the next neuron. The process repeats until the message has reached its destination. If the message is “don’t transmit information,” the message is not passed on.

3.1.2.1 Neurotransmission

When the electrical impulse that carries information reaches the end of a neuron’s axon, it is stopped at the tiny synaptic gap that separates them from the receiving neuron. The circuit is broken. Neurotransmitters are chemical messengers secreted at the synapse that have the potential to continue the circuit and transmit information between neurons.

Without neurotransmitters the brain could not process information or send out instructions to run the rest of the body. They affect the formation, maintenance, activity and longevity of synapses and neurons. Neurotransmitter molecules are produced within a specific type of neuron (different neurons are specialized in different neurotransmitters) and stored in tiny sacs known as vesicles. When an electrical signal reaches the vesicles, they release their neurotransmitters into the synaptic gap.

Each type of neurotransmitter has a unique shape that acts like a key. Released neurotransmitters attempt to attach to receptor sites (usually on the receiving neuron’s dendrites). Each receptor site is shaped like a lock that will fit only certain types of neurotransmitters. If the “key” fits, the neurotransmitter will send a message to turn on a receiving neuron (excitatory message) or off (inhibitory message).

When a neurotransmitter’s job is done, the receptors release the molecules, which are either broken down or recycled. Each neurotransmitter has a very specialized function. Some neurotransmitters carry emotional information that impacts our mood, outlook on life and behavior. For example, cortisol has an impact on our stress response system and dopamine has an impact on our motivation, satisfaction and pleasure. Serotonin plays a role in our mood management.

Figure 3.4

Action of SSRIs and NRIs

3.1.3 Growth and Development of the Brain

Brains begin development in the womb, starting as a neural tube and rapidly developing from the bottom up to form the lower, mid and outer brain. Development is impacted by the mother’s nutrition, stress, environment and other factors such as their mental health. During this time neurons migrate along the glial cells into place. The specific time table for migration is unknown and can be negatively impacted by the mother ingesting drugs or alcohol during pregnancy.

Babies are born with an estimated 86 billion brain cells. They create new connections, in the form of neural pathways, in response to active engagement in stimulating experiences. In the first few years of life more than 1 million new neural connections form every second (Center on the Developing Child, n.d.-a). Most neural pathways are created after birth as a result of stimuli coming from the environment that the child interacts with through the senses.

Each time the brain responds to a similar stimulus there is an increased propensity for the neurons to reconnect along the same pathway. Connections grow in the brain when experiences are repeated over and over or when an experience triggers a strong emotional reaction. The brain becomes hard wired to respond along established pathways. Think back to the opening story of the baby in the high chair dropping their spoon. That repeated experience with the caring adult is building pathways in the brain as they learn about cause and effect.

Neurons physically change as a result of this activation. Neurons grow new dendrite branches and receptor sites allowing the brain to process information more effectively and efficiently in more areas of the brain. The brain changes in response to experience by making connections between new input and what is already known and in place. The brain learns by recognizing patterns to make sense of new experiences. For example, when a baby tracks a toy with their eyes while grasping at it with their hand their visual and motor pathways are connecting and growing stronger. Experience literally sculpts the brain!

 

The most active period for creating connections is in the early years of life, but new connections can form throughout life. After this rapid proliferation early on, unused brain cells and connections wither away in a process called pruning. Pruning is necessary in order to make room for the pathways the child needs most to survive in their world. Creating room also has the function of making the remaining pathways more efficient. Think of how pruning a fruit tree is essential to make room for new growth and fruit to mature. Pruning too many neurons that are important will decrease the brain’s efficiency. Pruning happens most rapidly between ages 2 and 10, but is happening in some form throughout life, starting at about 8 months and ending in the late 20s (Cafasso, 2018). The intensity of the pruning is dependent on which area of the brain is being affected at the time.

 

3.1.3.1 Plasticity of the Brain

Plasticity is the term that describes the ease with which the brain can change itself. Our genes provide the blueprint, and our experiences are the architect. Which genes get turned on or off is determined by our experiences and environment. The brain’s pathways strengthen as they are used. As stated above, the neurons that are not used are subject to pruning, so it is a literal “use it or lose it” scenario. There is a remarkable increase in synapses during the first year of life. In the beginning of life the rate of connections is about 1 million per second (Center on the Developing Child, n.d.-a). The brain is most plastic early in life and it is easier to influence a baby’s brain than try to rewire parts of it in the later years.

3.1.3.2 Windows of Opportunity

There are some windows of opportunity in the brain for optimal growth. During certain stages of brain growth, parts of the brain become much more active in response to what the senses absorb, growing and learning faster than at any other time in life. Children need the right experiences at the right time for their brains to fully develop in these areas. Some areas in the brain have windows that are merely an easier time to learn a task (like a second language) and others are more critical. Sight is one of these critical windows of opportunity. If the eyes are deprived of sensory input early in life the neurons poised to connect for visual pathways reassign to areas in the brain where there is more experiential input happening (Eagleman, 2020). Most windows of opportunity are only optimal times and not absolutes. Every child is on their own timetable and so the age they reach the window will vary.

When developmental stages are interrupted or skipped, or an injury of any degree is experienced, some sensory-motor and cognitive functions may be impaired or missing. For most functions it is never too late to grow new neurons and pathways, but it gets increasingly harder to do as the brain ages. The human brain has a remarkable ability to heal. Windows don’t slam shut but slowly close as we age, never really shutting for good.

Figure 3.7

Human Brain Development

3.1.3.3 Enriched Environments

Children need active involvement in a stimulating, challenging and loving environment to cause the brain to grow and flourish. Passive involvement, isolation and an impoverished environment diminish the brain.

What is included in an enriched environment for the brain?

Sleep: babies, children and adult’s brains need adequate sleep (see table 1). Sleep is when the brain renews itself and cements learning.

Nutrition: brains need proper nutrition with the right types of fat, protein, fruits and vegetables. We are quite literally what we eat, and our brain can only function as well as the fuel we give it. Foods high in refined sugar are toxic for a growing brain. The American Association of Pediatrics recommends limiting the amount of sugar children consume each day to no more than 6 teaspoons for ages 2 and older; a typical child consumes more than triple that on average (Jenco, 2016). A great resource to make sure you are giving kids a balanced diet is MyPlate by the U.S. Department of Agriculture.

Water is also essential for the brain and body to stay hydrated. Encouraging children to drink water instead of juice is important to reduce the amount of sugar they are consuming while hydrating their brain. WebMD suggests the following: Toddlers need 2-4 cups, 4-8 year olds need 5 cups, 9-13 year olds need 7-8 cups and over 14 years need 8-11 cups (Wheeler, 2016).

Children need a safe environment with appropriate boundaries. Giving kids the freedom to explore while making sure that the environment is free from toxins and hazards helps young brains grow. They need the chance to interact with interesting materials and be given clear guidance about what is safe and not safe. We can think of boundaries as a fence we provide that surrounds the child and enlarges as they mature. The fence keeps them safe but within it they are free to explore and push against the boundary, so they know they are safe. Emotional warmth and safety is key!

Another important part of an enriched environment is positive role models and guidance. Adults should model the lifestyle and behavior they want from children. Eating healthy, drinking water, getting adequate sleep and exercise, and modeling emotional intelligence and growth mind set skills are all part of this. If the adults around children strive to keep their brains healthy chances are kids will follow suit. Positive guidance lets the child know they are safe. It is critical to remember that behavior is a learned skill just like tying their shoe. Both require activation of neurons to build strong pathways.

Young brains do best when media is limited, and they have daily exercise with time in nature. Movement of bodies creates an increase in the oxygen and blood flow to the brain, helping to keep it healthy at any age. Movement is important for not only keeping the brain healthy but also for improved mental health and school success. “For example, researchers found that children who had an opportunity to run for 15 to 45 minutes before class were less distracted and more attentive to schoolwork” (Wilson & Conyers, 2014, para. 5).

Nature provides the brain with a complex bath of sensory input that will strengthen pathways and connections in a way that can’t be replicated indoors, while helping kids build confidence, creativity and responsibility. “Many researchers agree that kids who play outside are happier, better at paying attention and less anxious than kids who spend more time indoors” (Cohen, 2023, para. 1).

In addition, our brains need down time and unstructured play. Down time for brains allows children to follow their own interests and develop mastery over skills they are learning. It is through unstructured play time that children feel free to learn about their world and strengthen their abilities. Young brains need practice repeating positive developmentally appropriate experiences with caring adults supporting them.

It is important not to stress the child by pushing them to do things they are not ready for or providing an overstimulating environment. The best approach is to follow the lead of the child and focus on their interests and unique timetables.

The child’s brain is not a smaller version of an adult brain. Neurons are still moving into position. As the brain develops, neurons migrate from the inner surface of the brain to form the outer layers. Immature neurons use fibers from cells called glia as highways to carry them to their destinations.

Table 3.1

Recommended Sleep By Age Group

Note: Data from the Centers for Disease Control and Prevention (2022).

3.1.3.4 Myelination

Mature neurons have axons that are coated by a fatty layer called myelin, the protective sheath that covers communicating neurons. Myelin acts in two ways: it provides substance for the brain and insulates the cells. The myelination of axons speeds up the conduction of nerve impulses, through an ingenious mechanism that does not require large amounts of additional space or energy. Areas of the brain do not function efficiently until they are fully myelinated. Babies are born without much myelin.

According to Harvard Health, “how the brain begins is how it stays” for the rest of life (McCarthy, 2018, para. 3), so it is important to make sure nerves grow and connect and get covered with myelin. The essential nutrients for brain growth include:

• Protein. Protein can be found in meat, poultry, seafood, beans and peas, eggs, soy products, nuts and seeds, as well as dairy.
• Zinc. The food that has the most zinc, interestingly, is oysters — but it’s also found in many meats, fish, dairy products, and nuts.
• Iron. Meats, beans and lentils, fortified cereals and breads, dark leafy vegetables, and baked potatoes are among the best sources of iron.
• Choline. Meat, dairy, and eggs have lots of choline, but so do many vegetables and other foods.
• Folate. This nutrient, which is especially important for pregnant mothers, can be found in liver, spinach, fortified cereals and breads, as well as other foods.
• Iodine. Seaweed is a great source of iodine, but we also get it from iodized salt, seafood, dairy products, and enriched grains.
• Vitamin A. Along with liver, carrots, sweet potato, and spinach are good sources of this vitamin.
• Vitamin D. This is the “sunshine vitamin,” and the best way to get it is to get outside. The flesh of fatty fishes such as salmon have it, as does fish liver oil, and products fortified with it, such as fortified milk. (McCarthy, 2018, para. 6)

Breast milk contains a fat almost identical to the fat in myelin, so if possible, mothers should nurse during the first year or more of life. Recent research has shown positive neurodevelopment and longer term cognitive outcomes for babies that are exclusively breastfed at least the first 3 months of life (Deoni et al., 2018). If formula is necessary, it is important to make sure they include ingredients as close to the composition of breastmilk as possible.

In order to protect a babies’ unmyelinated neurons, it is important to never shake a baby. Although there may be no outside sign of damage, the neurons get whipped around and have no myelin to protect them from the impact to the skull.

3.1.3.5 Boundaries and Readiness

The brain has boundaries around how quickly it can develop that are established by myelination timetables. Myelination can be stimulated when the brain is ready, but it cannot be rushed. Pushing a child to do something before they are ready can result in learning problems later on. Follow the child’s cues: their interest and frustration level will tell you when their brain is ready (or not) to learn a new skill.

Myelination continues to develop slowly all during childhood and adolescence in a gradual progression from lower to higher level systems. Early childhood is spent primarily on the brain stem, cerebellum and sensory cortex. Puberty is when the limbic system is primarily being myelinated and late adolescence is when the prefrontal cortex finishes myelination.

3.1.4 Layers of the Brain

The brain develops sequentially from the brainstem up, with the cortex developing last and continuously throughout life.

The Brain stem and midbrain are the first to develop and are mostly concerned with survival. The autonomic nervous system is regulated by the brain stem. It is the first part to mature. Babies are born with autonomic nervous system neurons fully myelinated. These neurons control survival needs such as heartbeat, breathing, and sucking. The brainstem and midbrain monitor the outer world through sensory input and activate the body to respond in ways that ensure self-preservation. The brain stem processes information at a subconscious level; it is quick and reactive. Some of its functions include autonomic nervous system, fight/flight/freeze/fawn response, defense mechanisms, territoriality, reflexes, rote responses, routine, and habits. It is the least plastic layer of the brain and the most highly resistant to change. The reason habits are so hard to break is because they reside in this region of the brain.

The Cerebellum is mostly in charge of coordination. It controls automatic movements and the coordination of movement and thought or balance. The cerebellum is where procedural memory is stored like our motor skills. It does not involve conscious thought except when we are first learning something (like riding a bike). This area of the brain matures in early childhood and works in coordination with the brain stem.

The limbic system is where emotions are processed. The limbic system is made up of many structures in the middle of the brain including the amygdala, hippocampus, thalamus, and olfactory bulbs. This area receives, interprets, and responds to emotional signals sent from the body. It processes information at the subconscious level and forms emotional patterns. This area is also associated with long term memory and matures during puberty.

The cortex is where higher level thinking at the conscious level occurs. This includes, making sense of the world, decision making, creativity, reason, logic, imagination, self-awareness, and self-control. Everything that makes us uniquely human is the result of the interplay between the cortex working in harmony with the lower brain structures. The cortex loves change, novelty, fresh input and variety. It is the most plastic layer of the brain. The cortex is divided into specialized areas called lobes that are determined by their function. It matures over a long period of time, from the back to the front of the brain.

3.1.5 Lobes of the Brain

The cortex is split up into areas that are responsible for different functions. The back and side lobes are mostly related to sensory functions.

The occipital lobe is mainly responsible for vision and develops very early. The temporal lobe processes hearing, speech, language, and memory. The parietal lobeprocesses incoming sensory information like touch, pressure, pain, cold, heat, taste, and proprioception. The frontal lobe is responsible for gross and fine motor movements.

The prefrontal lobe, the very front section of the frontal lobe, is responsible for critical thinking, creative thinking and problem solving. It is the part of the brain that allows us to imagine, plan and rehearse future actions. This area connects to the limbic system to regulate emotions. It is this integration of emotions with thought that is essential to the decision-making process. This area of the brain starts to develop around 8 months and continues to develop late into adolescence (around age 26).

Executive function and self-regulation are also associated with this area of the brain. A child who develops the ability to self-regulate has better impulse control, mental flexibility, and emotional intelligence. These functions are critical for learning. Although children do not have executive function from birth, it can be strengthened through practice with games and activities specifically aimed at reinforcing these skills.

3.2 Connecting Brain Development to Early Childhood Education

Now that we have a basic understanding of the building blocks of the brain and how it develops over time, it is important to understand how this knowledge can help us create brain healthy early childhood experiences for all children. The following section will discuss the importance of creating environments and interactions that help the brain grow and give it the best possible opportunities for cognitive and emotional outcomes.

3.2.1 Media and Screen Time

The developing brain needs positive interactions with caring adults in an enriched environment for optimal growth. Interactions with media or screens can be detrimental to this development as it deprives the brain of multisensory interactions which are necessary for neuronal growth. Media includes phones, television, computers and anything with a screen. The Academy of Pediatrics (AAP) has recommended limited media for all ages and adding emphasis on in-person interactions. Research by AAP has found that using:

A healthy Family Media Use Plan that is individualized for a specific child, teenager, or family can identify an appropriate balance between screen time/online time and other activities, set boundaries for accessing content, guide displays of personal information, encourage age-appropriate critical thinking and digital literacy, and support open family communication and implementation of consistent rules about media use. (Chassiakos et al., 2016)

They recommend none or very limited screen time for children under 2. If media is used they suggest that an adult be present and interact with the child while watching and limit this to video chatting. For children 2-5 they recommend a max of 1 hour per day of viewing. School age children should be limited to no more than 2 hours per day. They suggest adults co-view with all children so that they can reinforce lessons and point out stereotypes and bias that may be hurtful. It is also important to consider the type of media they are consuming, passive viewing has a different brain impact than creating content or interactive games. Adults need to select high quality programming for young children that is educational (Chassiakos et al., 2016).

The American Academy of Pediatrics shares important information about why limited media use for children is important (note that they use the term “behavior problems”; a strength-based way to reframe this would be to say “behavior challenges” or “unwanted behaviors”). This guidance from AAP recommendations on media use for children (2016) is summarized below from EduResearcher (Marachi, 2016):

Overuse of digital media may place your child at risk of:

• Not enough sleep. Young children with more media exposure or who have a TV, computer, or mobile device in their bedrooms sleep less and fall asleep later at night. Even babies can be overstimulated by screens and miss the sleep they need to grow.
• Delays in learning and social skills. Children who watch too much TV in infancy and preschool years can show delays in attention, thinking, language, and social skills. One of the reasons for the delays could be because they interact less with parents and family. Parents who keep the TV on or focus on their own digital media miss precious opportunities to interact with their children and help them learn.
• Obesity. Heavy media use during preschool years is linked to weight gain and risk of childhood obesity. Food advertising and snacking while watching TV can promote obesity. Also, children who overuse media are less apt to be active with healthy, physical play.
• Behavior problems. Violent content on TV and screens can contribute to behavior problems in children, either because they are scared and confused by what they see, or they try to mimic on-screen characters. (para. 8)

The Common Sense media website has wonderful resources for parents and teachers and even has lessons for school age to help develop positive media habits for kids.

3.2.2 Social Emotional Development: The Limbic System

One of the first brain constructs to develop before birth are those that process emotion. Early emotional experiences form a kind of template that continued emotional development is built on. These experiences have a disproportionate importance in organizing the mature brain. Emotions develop in layers, each more complex than the last as the child responds to their emotional environment. Emotional learning becomes ingrained as experiences are repeated over and over.

The Prefrontal cortex regulates emotional responses and is developed and connected with the limbic system early, between 8 and 18 months of life. These neural pathways in the limbic system and prefrontal lobes provide the framework for emotional intelligence.

Peter Salovey (a Yale Psychologist) and John Mayer (a University of New Hampshire psychologist) first proposed that we also have emotional intelligence (1990). Daniel Goleman popularized this concept in his book Emotional Intelligence (1995).

Emotional Intelligence (EI)consists of a person’s abilities in 5 main areas or domains (Goleman, 1995):

Self-Awareness –the ability to recognize or know feelings as they are happening and using them to make life decisions you can live with. This includes pleasant, unpleasant and multiple emotions at once. It is critical we teach children about all their feelings and give them a wide range of emotional labeling (see Figure 3.12).

Mood Management –the ability to handle distressing emotions in appropriate ways to maintain our wellbeing.

Self-Motivation –the ability to persist in the face of setbacks and channeling your impulses in order to pursue your goals.

Empathy – the ability to recognize and share another’s feelings.

Social Arts – the ability to interact with others in positive and socially acceptable ways.

Emotional Intelligence is important because studies have shown that higher emotional intelligence is a better predictor of success in children than IQ (Durlak et al., 2011). Kids who participated in social emotional learning (SEL) programs at school had significantly improved social and emotional skills, attitudes, behavior and academic performance.

In order for emotional intelligence to develop, children need to feel secure and that their needs for survival are being met. The fundamental task of an infant is figuring out how to get their needs met in their world. Children need to feel loved and emotionally secure. It is essential that they have a consistent, nurturing relationship with the same caregiver early in life in order to develop a secure attachment.

Attunement is critical to the development of EI. This is when a child’s inner feelings are accepted and mirrored back to them by caregivers. “The brain uses the same pathways to generate an emotion as to respond to one” but “if emotions are repeatedly met with indifference or a clashing response,” they may “fail to strengthen” or be eliminated (Begley, 2010, para. 15). Feelings mirrored back to children help them develop self-awareness, the foundation of Emotional Intelligence. It is important to teach and help label a wide range of feelings when interacting with kids. Using a feelings wheel in your classroom is a great way to expand the range of feelings you teach.

3.2.3 Stress and Trauma

3.2.3.1 The Impact of Stress

Stressis defined as a “physical, chemical, or emotional factor that causes bodily or mental tension and may be a factor in disease causation” (Merriam-Webster, 2024). Stress is a normal part of life and our brains are capable of handling stressful events in a positive way if given the right experiences in childhood. In general, there are two types of stress: positive stress or eustress and negative stress or distress. Which type of stress we experience, how much and how we interpret it all impact how damaging stress is to our systems.

Neural pathways run from the eyes, ears and other sense organs to a central clearing house deep in the brain called the thalamus. The thalamus works with the hypothalamus and amygdala to pass on the information to the higher levels of the cortex. They act like a gate to pathways that run to the cortex and are activated by how we feel about the information being processed by the limbic system (Zhang et al., 2019).

When we experience a positive emotion, are actively engaged, or appropriately challenged, while retaining a sense of control, we experience eustress. The thalamus opens the gateway, or upshifts, to the cortex where higher level thinking takes place.

When a threat is perceived, we experience distress. The thalamus quickly sends a message to the amygdala that there might be danger. The amygdala, acting as an alarm company, activates a cascade of chemicals (neurotransmitters and hormones) involved in the stress response: freeze-flight-fight-fawn. This distress closes the gate to the main road to the cortex and the brain downshifts to the lower survival brain, resulting in freeze-flight-fight-fawn responses instead of higher level problem solving (LeWine, 2024). The good news is that at the same time, another slower pathway moves up to the cortex- like a detour route. We can now access the prefrontal lobes to modulate our emotional reactions. This helps us make a rational decision about how to respond to an emotional trigger.

Figure 3.14

Brain Side View

Some emotional reactions bypass the cortex and can be formed without any conscious, cognitive participation at all. The degree of control we perceive we have over the threatening situation determines whether this hi-jacking will take place. If the brain continues to perceive the situation as a threat the stress hormone cortisol, is released and keeps the body revved up and on high alert. When the threat passes, the cortisol level will decrease.

New research is finding that the vagus nerve plays an important part in how the body interprets sensory input and reacts with fight/flight/freeze/fawn. If the vagus nerve senses threat the child becomes deregulated and the parasympathetic response takes over. It is important to help the child regulate their body by helping them to calm the vagus nerve. You can do this through movement and breathing activities along with other sensory experiences like playing with playdough. Co-regulating with the child when they are younger and even as they age, can help them to build the ability to regulate themselves as they get older (Bornstein & Esposito, 2023). Co-regulation is the interactive process by which caring adults (1) provide warm supportive relationships, (2) promote self-regulation through coaching, modeling, and feedback, and (3) structure supportive environments (Rosanbalm & Murray, 2017).

Research by Kelly McGonigal of Stanford University found that how we view stress makes a difference in how harmful it is. There are 3 ways to change our perception of the stressor effectively; 1) View your body’s stress as helpful and energy you can use, 2) view yourself as capable of handling and learning from the stress and 3) view stress as a common problem everyone deals with (as cited in Parker, 2015).

Children need experiences that help them develop a strong stress-response system so that they recover from stressful situations quickly and build stronger pathways between the limbic system and prefrontal lobe in their brain. The main way adults can help build this healthy stress response system is a process called serve and return The Center on the Developing Child at Harvard University (2019) suggests 5 steps to build positive brain pathways through serve and return practices:

1. Notice the serve and share the child’s focus of attention. It is important to pay attention to what the child is focused on and follow their lead on the interaction.
2. Return the serve by supporting and encouraging. Offer comfort when they are distressed, play with them, be curious about what they are doing. Mirroring their thoughts and feelings lets them know they are seen and understood.
3. Give it a name! Name what a child is seeing, doing, or feeling will make important language connections in their brain, even before they can talk or understand your words. This helps them understand the world around them.
4. Take turns…and wait. Keep the interaction going back and forth. Make sure to take time to let the child respond to you as you take turns interacting. They need time to form responses as they are learning so many things at once.
5. Practice endings and beginnings. Sharing focus with a child helps you know when they are done. Did they turn away, fuss, or walk away? Let them take the lead and be sensitive to when they are ready to start something new.

Think back to the opening story of the baby in the high chair. This loving exchange between the adult and baby is a practice of serve and return.

When children are experiencing extreme amounts of stress and are not getting the positive interactions to mitigate it, they are experiencing what is known as toxic stress .

3.2.3.2 Adverse Childhood Experiences

Too much toxic stress in a child’s life can damage the developing brain and lead to life-long problems in learning, behavior, and physical and mental health. Toxic stress can come from extreme poverty, repeated abuse, or severe maternal depression. These situations or experiences are also called Adverse Childhood Experiences or ACEs and are a cause of prolonged toxic stress. Many studies have confirmed the negative impact of ACEs on the health and wellbeing of children and adults (Webster, 2022). The Center for the Developing Child at Harvard University has a wealth of information about the impact of toxic stress and ACEs; there is also evidence of how racism is connected to poor outcomes for children due to the impact of this as a toxic stress on child development (n.d.-b). Toxic stress impacts a growing brain’s development by causing neurons to have fewer connections in the limbic and prefrontal cortex, the areas of the brain that control emotional reactivity. It is important to remember that ACEs scores are not meant to be diagnostic and should not be used to make clinical decisions (Pondiscio, 2020).

Figure 3.15

Toxic Stress and Brain Architecture

3.1.3.2.1 Cortical Modulation

When a child experiences toxic stress or ACEs, the higher regions of the brain become less developed since the brain is constantly activating the pathways to the lower, survival regions of the brain. Neuroscientist Dr. Bruce Perry (1997) developed a model for understanding the functioning of the layers of the brain in connection to each other called cortical modulation. In other words, how do the higher layers modulate the lower levels of the brain? He has demonstrated that most brains that have experienced high ACEs will not function as optimally as brains who have had adults help them develop a strong stress response system. When looking at the number of connections in each of the layers in children’s brains we see a difference in their function based on their experiences.

In a healthy brain where a child has low ACEs, the higher levels or cortical areas of the brain have the most connections, and higher ratios. The thinking part of the brain is the strongest and therefore a child would have a strong stress response system developing. The brain of a child with high ACEs will have a ratio where the lower regions of the brian (brain stem etc.) are bigger than the higher thinking regions (cortex). In these brains the lower regions of the brain have more connections and thus downshifting happens in the brain more readily (Perry, 1997).

3.2.3.2.1 Resilience

Some children who experience ACEs and toxic stress can develop brains with better ratios than others, even within the same family. We consider these children to have resilience. Resilience requires supportive relationships and opportunities for skill building. These relationships can be outside of the family, for example a teacher or coach, and are the active ingredient for developing resilience. If children experiencing ACEs have access to these positive experiences, their brain can reverse the ratio and develop a greater ability to handle the stress in their lives. These experiences are called “Positive and Adverse Childhood Experiences,” or PACEs, and have a mitigating impact on ACEs, leading to the best developmental outcomes for children who become adults who are flourishing (Audage, 2021). A child’s temperament can also be a factor in developing resilience (Center for Child & Family Well-Being, n.d.).

3.2.4 Trauma Informed Care and Education

Understanding how the brain develops and what can happen if children do not get positive, caring experiences at home, helps teachers create classrooms that will benefit all children. One of the keys to creating trauma informed care is understanding what the brain needs in order for a more optimal outcome. We need to move from blaming the child to understanding them. Providing consistent care and attachment with a teacher who is loving and compassionate is essential. Classrooms must be built to allow for healthy, developmentally appropriate experiences that provide an enriched environment for young brains to flourish.

Social Emotional Learning (SEL) programs in schools are helping children develop skills to build strong pathways between the limbic and cortex layers of the brain (Calhoun et al., 2020). These programs have demonstrated success in building a child’s resilience and emotional intelligence.

3.2.4.1 Elements of Trauma Informed Care (TIC)

According to Erdman et al. (2020), there are several elements that are an essential part of helping kids overcome trauma and develop resilience. The first element is a safe and inviting environment that includes structure, a variety of materials and providing thoughtful choices for children’s activities. Secondly, children need strong, loving relationships with adults and their peers. These can be fostered by following a child’s lead and implementing training in mindfulness. The third element is an awareness of the importance of play for a child’s optimal development and also for helping them learn to effectively manage stress. Lastly, they stress the importance of connecting with families to create supportive partnerships. The researchers stress that we must not just treat individual behaviors but the whole child and to remember that creating a trauma sensitive classroom benefits all children.

 

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Websites you may want to explore further

Beyond Screen Time: Help Your Kids Build Healthy Media Use Habits, HealthyChildren.org

Center on the Developing Child, Harvard University

Common Sense Education, Digital Citizenship Curriculum

Institute for Learning and Brain Sciences, University of Washington

MyPlate, U.S. Department of Agriculture

Sleep Foundation

Washington Department of Child Youth and Families

Zero to Three

 

Chapter Attribution

“Chapter 3 Brain Development by Christine Moon” is CC by 4.0