Always Room for Growth

This Halloween I joined my fellow undergrads, along with graduate students and scientists from the nearby Oregon National Primate Research Center, for a visit to Dr. Martin Luther King Junior Elementary School in Portland, Oregon. We were met by a crowd of superheroes, witches, TV characters and wild creatures who were eager to learn about the brain. They got to examine real cerebrums from various animals (there were incredible specimens from the ONPRC!) and even a few human noggins, too.

LEARN MORE: A Hippocampal Halloween

Through outreach I’ve seen a huge difference between how a first grader and a fifth grader each think and act – but I’ve also encountered similar differences between two first graders. This diversity can be partly explained by ongoing research on the different effects that childhood experiences have on the changing brain being conducted by the Adolescent Brain Cognitive Development (or ABCD) study.

The study involves tracking the biological (both structural and functional organization of the brain) and behavioral changes that participants experience as they reach young adulthood. ABCD not only focuses on how the brain changes in these participants but also examines the effects that stress, trauma, video games, social media, family life and other factors have on development. The objective of the study is to truly understand adolescent development, to encourage evidence-based educational policies and curriculum changes, and to develop resources to help promote healthy brain development.

LEARN MORE: ABCD: About the study

LEARN MORE: Adolescent Brain Cognitive Development® Study (ABCD Study®)

LEARN MORE: A practical guide for researchers and reviewers using the ABCD Study and other large longitudinal datasets

LEARN MORE: Youth screen use in the ABCD® study

LEARN MORE: The subcortical correlates of autistic traits in school-age children: a population-based neuroimaging study

LEARN MORE: Multimethod investigation of the neurobiological basis of ADHD symptomatology in children aged 9-10: baseline data from the ABCD study

LEARN MORE: Multiple measurement analysis of resting-state fMRI for ADHD classification in adolescent brain from the ABCD study

LEARN MORE: Attention-Deficit/Hyperactivity Disorder: Restricted Phenotypes Prevalence, Comorbidity, and Polygenic Risk Sensitivity in the ABCD Baseline Cohort

LEARN MORE: The DSM-5: Classification and criteria changes

Experiences play a part in the variability we see amongst children of the same age group. Genetics also contribute. But besides these observed differences within an age group, through outreach I also noticed a difference in the development of the brain and behavior between the different grade levels.

LEARN MORE: Genetic and Environmental Contributions to General Cognitive Ability Through the First 16 Years of Life

Synaptogenesis: New synapses, new connections

Let’s start with kindergarteners, who possess such big brains for their small bodies. Do not underestimate this bunch because they will ask you logical questions such as “how does my brain know it’s night?” but will also ask “can you eat brains?” (That one is kind of a perfect question for Halloween!)

Most kindergartners are five years old which means that their brains are not even close to being fully developed. Brains continue developing until early adulthood which means there’s certainly room for improvement in the average kindergarten brain. Influential theories of child development hold that children’s brains develop in stages, with an important period spanning ages 2 to 7 years old.

LEARN MORE: Child Development and Early Learning

LEARN MORE: The developmental stages of L. S. Vygotsky and J. Piaget: A comparison

LEARN MORE: Cognitive Development

LEARN MORE: Piaget

LEARN MORE: Brain Basics: The Life and Death of a Neuron

LEARN MORE: Dendritic Spine Initiation in Brain Development, Learning and Diseases

LEARN MORE: A Fragile Balance: Dendritic Spines, Learning, and Memory

LEARN MORE: Brain Basics: Know Your Brain

Synaptic pruning

Synaptic pruning is the process by which the brain removes synapses (and sometimes entire neurons) it does not need anymore to make way for better and more effective neural connections and networks.

IMAGE SOURCE: Synaptic growth, synesthesia & savant abilities

The first and second graders I’ve met seem to be undergoing major behavioral changes during this critical period of brain growth. These two grade levels, mostly six and seven year olds, are experiencing the effects of all the new synapses formed during the last few years of their lives. Their brains are busy pruning back many connections, and strengthening others, to develop more effective networks. The life experiences and learning they’ve had has prepped their noggins to take on new challenges, like reading longer texts, counting money, math, grammar skills – and of course some basic neuroscience!

One of the major differences I saw in this age group was their improved ability to observe and follow directions, and ask more difficult questions. I took questions like “How does my brain know I stomped?,” “Can our brain die and how does our brain know that we died?” and “How do our ears hear sounds?”

LEARN MORE: Core Concept: How synaptic pruning shapes neural wiring during development and, possibly, in disease

LEARN MORE: Adolescent Neurodevelopment

Myelin Matters

Third graders begin to show more logical thinking than their younger counterparts. They start to hit you with MUCH harder questions such as “How does my mind know I am in pain?” or “Why do I fall asleep?” or “How are memories formed?” This age group benefits from the major alterations, pruning and fine tuning in connections from their brains being challenged and changed during earlier grades.

White matter (myelinated axons) is responsible for the transmission of information and allows for better functional coordination of developing networks of brain regions that allow for memory, attention, social decision making and other aspects of cognition. In third grade you start studying even more challenging topics which requires your brain to work harder and faster. Yet it also requires your brain to differentiate and know when to give a task or concept more attention or when to free up resources in the brain.

“As neural networks form, the child learns both academically and socially. At first, this learning is mostly rote in nature. As skills become more automatic, the child does not have to think as hard about what he or she is learning or doing, and brain resources are freed up to be used for complex tasks that require more and more attention and processing. Skills in reading, mathematics and writing become more specialized and developed.”

— American Psychological Association

The days of learning how to count money and basic addition and subtraction have passed. Third graders are studying fractions and decimals, punctuation, multiplication and division, as well as how to revise and edit sentences and short papers, topics that require more complex engagement to learn. The brain has acquired many abilities that no longer require direct conscious involvement, and kids can call on them implicitly, freeing up their attention to develop even more complicated skills.

LEARN MORE: Research in Brain Function and Learning

LEARN MORE: Developmental Biology of Myelin

LEARN MORE: Myelin development in cerebral gray and white matter during adolescence and late childhood

Fourth and fifth graders are taking on their final years of elementary school and at the same time are being met with more social pressures and fears. Their brains are more developed, neural connections and networks are getting established, and students are constantly challenged with new information.

One fifth grader noticed the 3D printed heart on my table and proceeded to name all the different ventricles and point out the aorta. A fourth grader was explaining to me how the brainstem plays a vital role in our balance. A question we were asked by the previous grades was “Why is our brain pink?” which turned into “What’s the difference between the white and gray matter?” in the older age group.

LEARN MORE: Cognitive neuroscience: the biology of the mind and findings and current opinion in cognitive neuroscience

LEARN MORE: Maturation of the adolescent brain

LEARN MORE: Age differences in short-term memory binding are related to working memory performance across the lifespan

There is always room for growth in the brain.

Seeing first hand the leaps in understanding and cognitive development in young children as they go from one grade to the next has been incredible. As we get older we forget how much knowledge we have gained over the years and how the journey towards adulthood begins at this age. Our brains experienced synaptogenesis, synaptic pruning, myelination, and the acquisition of networks allowing us to attend, perceive, decide and remember. We may not recall the changes but we reap the benefits today.

Comments are closed.