Neuroscience

What’s Going On Inside A Toddler’s Brain, According To Science

Is your 2-year-old trolling you?

by Patrick Sauer
Updated: 
Originally Published: 
Kelsey Wroten

As the parent of a toddler, your big adult mind is always trying to make sense of what’s going through their tiny kid one. “Why are you flopping on the ground?” “Why are you biting me for no particular reason?” “Why are you peeing yourself while maintaining eye contact?” The biggest issue is that you don’t know what they’re thinking, and they can’t tell you yet. But science can.

Dr. Dean Burnett, a neuroscientist (and author of the Idiot Brain, and Guardian columnist who moonlights as a stand-up comic), says that the early days of brain development are fascinating because all of the connections needed throughout life are forming and coming together. Dr. Burnett is also father to a 4-year-old son and a one-year-old daughter, so this is basically applied science. Here’s why your kid’s still-forming gray matter makes their behavior anything but black and white.

Your Kid Is Dory From Finding Nemo

Adults have mental models based on experience and the memory of how things should work. These are schemas to organize situations. Young children don’t. “Everything for toddlers is new and exciting; they don’t have a wealth of experience on how to judge things,” says Dr. Burnett. In fact, kids younger than 7 are basically hardwired to not store many memories. Since they’re not Arnold Schwarzenegger, you can’t assume a child will have total, or even partial, recall.

Repetition Vs. Comprehension

The brain doesn’t grow in the exact same way as the rest of the body. A kid can master crawling through repetition, but that doesn’t mean they will grasp the concept of why they need to put on shoes. What toddlers do understand is that when something is different than the day before, it sets them off. “All the connections in their brains aren’t made yet,” says Dr. Burnett. “When their expectations aren’t met, toddlers have lost control. They don’t know how to react, so they get distressed and sound the alarm bells because you’ve given them a red sippy cup instead of the green one.” (To be fair, that red sippy cup is superior.)

Small Brains Work Twice As Hard

“There’s actually a lot more connections in a child’s brain than in adult one,” says Dr. Burnett. “It isn’t until adolescence that the process of pruning begins, whereby the brain starts losing memories that aren’t ever activated to be more efficient.” Yes, your toddler is processing too much, not too little, which should blow both your minds. Conversely, teens are doing a ton of pruning, which is why they’re always sleeping instead of mowing the lawn.

It’s All Fight Or Flight

There’s a safety detection system that resides deep within the brain, right around the hippocampus, which triggers the “fight or flight” response to high-stress situations. Some of the potentially-lethal things to avoid are part of the evolutionary process (spiders, snakes), while others are learned human behaviors (roller coasters, Phish concerts). A young child’s brain doesn’t recognize the difference. What’s benign to grown-ups isn’t necessarily to toddlers. “They don’t know when a thing is harmless, they just know it’s unfamiliar, which can set them off,” says Dr. Burnett.

The Evolution Of Screaming

Your toddler’s freak-out over anything (everything?) is to be expected. It’s a form of self-preservation. “From an evolutionary standpoint, part of the reason a child cries and throws a tantrum is to get the most possible attention from an adult within a group or community,” says Dr. Burnett. Flailing and wailing can both scare off predators and call an adult, which makes screaming fits a biological imperative. You can share this exciting scientific discovery the next time you bring your kid on a plane.

They’re Not Tasting Broccoli The Same Way

We all want to teach our kids to be good eaters. But, there’s a cerebral reason children prefer birthday cake over, say, broccoli cake. “Toddlers have different taste sensations, foods can be more vivid for them, so spinach and broccoli may be more bitter or sharp, says Dr. Burnett. “As opposed to ice cream, which is full of sugar. The brain likes it because it’s high energy, so treats will be sought out.” Well, if nature says you should eat this doughnut…

Doomed to Repeat the Past, Only Louder

You thought that, as kids move out of the toddler years, things get more mature. Wrong. As their brains form more permanent memories, kids can be even harder to handle. “At, say 5 years old, children have a base level of understanding, which can make crying fits worse because they have a sense of how things should go,” says Burnett. Tantrums may be infrequent, but they can be doozies because kids, like adults, have to work through their anger. It’s the difference between a toddler melting down for a minute before being distracted by a shiny object, versus a kindergartener’s entire world collapsing when you turn off Doc McStuffins.

The Good Will Hunting Takeaway

A toddler’s head is a complex place. But think about how chaotic your fully-formed brain can be — and you’ve had 30 to 40 years operating it. Dr. Burnett says parents should always remember, it’s not their fault. “They don’t mean it,” he says. “They don’t want to keep you up all night, ruin your schedule, or make your life actively harder.” Or maybe science just hasn’t discovered your kid’s long con, yet.

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