4 Things That Happen to Your Child’s Brain When You Play with Them, According to Science

The mysteries of the growing brain are myriad—such as why toddlers have quicksilver moods and why 4 years is the magic age they master blunt-tip scissors. But the last few decades of research on the early years of brain development have yielded some fascinating facts, as well as best practices for parents to follow. One of the most surprising avenues of research involves the child’s brain during play—not violin learning, multiplication memorization or even Baby Beethoven listening, but simple caregiver-to-young’un play time. This often-undervalued period of a child’s day has been found to be a fertile time for all kinds of growth. So we asked experts to parse the science and give us the top line of what’s going on in those little heads. (Hint: It’s quite a lot of activity.)

Stefanie Lattner is CEO of WeVibin Inc., a company focused on nonpharmaceutical solutions for improved cognitive performance in adult ADD, anxiety, autism, TBIs and sleep/relaxation. Also in the biotech industry, she served as head of research at Respironics, amassing a patent portfolio of over 85 patents worldwide related to brain health. She has helped to launch several startups and has a master’s degree in bioengineering from University of Pittsburgh as well as an MBA from the Stephen M. Ross School of Business at the University of Michigan.

Sanam Hafeez is a New York State licensed psychologist and a New York State certified school psychologist. She founded Comprehensive Consultation Psychological Services in 2006 to serve the community with neuropsychological, educational and developmental evaluations with a focus on bilingual and culturally sensitive assessments. Her specialties include forensic evaluations involving custody, competency and immigration; expert witness testimony, learning disabilities, autism, ADHD, traumatic brain injury and psychopathology including bipolar, schizophrenia, depression and anxiety. She has a Doctor of Psychology degree from Hofstra University.

Bioengineer Lattner says that, as living organisms, we’d do well to remember that everything in our environment, from our food to whatever else we taste, touch or smell, has a biochemical effect in our brains. “What research has shown is that, in play, chemical reactions occur—dopamine gets all the press, but also in play there are chemicals reinforcing social bonds and aiding in future development.” A roster of playtime chemicals includes:

• Dopamine: signals to the child “hey, this is fun”
• Oxytocin: releases reinforcing bonds between playmates
• Endorphins: enhances mood
• Serotonin: regulates mood
• Acetylcholine: supports attention, learning and memory
• GABA: stabilizes mood

The brain isn’t like, say, the kidney, an organ that is pretty much standard issue and then gets filled with whatever bodily fluids it’s assigned to manage. (That said, we love your work, kidneys.) Brains are organs that grow into their shape—what’s called their brain architecture—according to the tasks they are given to manage (for example, a Major League pitcher’s brain is probably going to develop differently than a nuclear engineer’s). Sportsman or scientist, each of us has our own unique brain architecture, made up of billions of connections between individual neurons in the brain, an ongoing process from before birth into adulthood.

At the same time your child’s brain is building its architecture by creating new synaptic connections, it’s also streamlining connections that are deemed to be less important. “It’s called ‘pruning’,” Lattner says. “So whatever you are exposing a child to, say visually or tactilely, helps them figure out what to keep and what to get rid of.”

Another physical change occurring in early childhood is myelination, or the formation of a sort of insulation sheath around nerves that helps them conduct better. “Myelination continues through childhood and adolescence, it’s the white matter of the brain,” Lattner says. “If that’s not mature, that causes the nerves not to fire rapidly.”

For example, when you throw a ball to a toddler, they have to use sight, hearing and decision-making to react. And the attention, motor control and even something as simple as holding their little bodies upright (think of a toddler toppling over while playing) are all a result of neural functions. All the nerves have this ability to work in concert because they’ve had practice during play time—not exclusively play time with adults, but since adults generally have a more practiced and empathic simple play ability than other small children, it’s a great foundation.

Play time activates the prefrontal cortex, which is the part of the brain responsible for making plans, regulating emotion and solving problems. "Emotional intelligence refers to the ability to recognize, understand, manage and effectively use one's own emotions, as well as the ability to understand and influence the emotions of others," says Hafeez. When playing with adults, who have developed a more sophisticated emotional intelligence than kids, children are able to model their behavior on the adult's actions and develop in a socially accepted manner.

In free play, a child's lower brain regions are engaged when they move, emote and make choices about what to do, which gives them a feeling of control in their world. Additionally, lower brain regions are engaged during emotional involvement during play time, which is why playing with your kids brings you closer to them. "The child experiences undivided attention during play, fostering a deep emotional connection," says Hafeez. "The emotional safety provided by play contributes to the child's overall emotional well-being, helping them navigate life's challenges with a sense of security and confidence." That explains how, if you want to strengthen your connection with your kid, playing with them not only fosters closeness, it also associates you as a parent as a path toward learning and growth.