If you’ve ever found yourself queasy on a road trip, staring out the window to stave off nausea, you’re not alone.
But here’s the twist: that unsettling feeling might actually be a sign your brain is doing exactly what it’s supposed to do—or at least trying its best.
Recent studies suggest that car sickness is the result of a clash between your senses and your brain’s ancient survival instincts.
The brain, in its quest to keep you alive, sometimes makes a misguided assumption: that you’ve been poisoned.
This might sound bizarre, but here’s why it happens. When you’re in a moving car, your eyes perceive the stationary interior of the vehicle, while your inner ear senses motion as the fluid inside it shifts with the car’s movement.
This mismatch in sensory signals leaves your brain confused. And when confusion strikes, the brain reverts to one of its oldest defense mechanisms: purging potential toxins.
As neuroscientist Dean Burnett explains:
“As soon as the brain gets confused by anything like that, it says, ‘Oh, I don’t know what to do, so just be sick, just in case.’”
The Evolutionary Mismatch That Makes You Sick
To understand why your brain jumps to the poison conclusion, it’s essential to consider evolution.
Humans have only recently started traveling in vehicles—cars, boats, and planes—which means our brains haven’t fully adapted to this modern experience.
For most of human history, motion accompanied by a stationary body was uncommon, except in one key scenario: poisoning.
In ancient times, consuming neurotoxins could lead to dizziness and disorientation.
Vomiting became the body’s go-to way to eliminate harmful substances. Fast forward to today, and your brain is still applying this primitive logic, even when you’re perfectly safe in the backseat of a car.
It’s Not Just in Your Head
Contrary to the assumption that motion sickness is purely psychological, there’s concrete evidence to the contrary.
The inner ear’s vestibular system—the balance mechanism that relies on fluid-filled tubes—plays a critical role.
When you’re sitting still in a moving car, this system senses motion, but your visual field says otherwise.
This sensory conflict creates a cognitive puzzle for your thalamus, the brain’s information-processing hub.
Unable to reconcile the signals, it defaults to an alarmist response: “Better safe than sorry—get rid of potential toxins.”
Why Some People Are More Prone Than Others
Here’s where things get even more intriguing: not everyone experiences motion sickness the same way.
Researchers have identified a few factors that might explain this variability:
- Body Sway: A 2013 study revealed that individuals who naturally exhibit more body sway—even when standing still—are more likely to experience motion sickness. This suggests a heightened sensitivity to balance and motion.
- Evolutionary Luck: Genetics may also play a role. Some people may have inherited a more adaptable vestibular system, making them less prone to sensory mismatches.
- Age and Adaptation: Many children experience motion sickness but seem to “grow out” of it as their brains adapt to modern travel. However, scientists aren’t entirely sure why this happens.
Practical Tips to Outsmart Your Brain
While a permanent cure for motion sickness remains elusive, there are practical ways to manage it:
- Look Out the Window: Focusing on the horizon provides visual confirmation of motion, helping to resolve the sensory conflict.
- Avoid Reading: Reading a book or scrolling on your phone worsens the mismatch, as it reinforces the illusion that you’re stationary.
- Drive, If You Can: Drivers are less likely to experience motion sickness because they’re actively engaged with their environment and in control of the movement.
- Listen to Music: Calming music can reduce stress and distract your brain from its confusion.
- Eat Smart: A light, protein-rich meal before travel can help stabilize your stomach.
What Science Still Doesn’t Know
Despite these insights, many questions remain unanswered.
Why do some people never experience motion sickness, while others feel nauseous even on short trips? What determines why some individuals outgrow it while others don’t?
Research continues to delve into these mysteries, with the ultimate goal of developing effective treatments.
In the meantime, you might find comfort in knowing that your queasy stomach is evidence of your brain’s evolutionary determination to protect you—even if it’s a little misguided.
Rethinking Motion Sickness
So the next time you find yourself carsick, remember this: it’s not just an inconvenience—it’s a fascinating glimpse into the way your brain evolved to prioritize survival.
As Dean Burnett puts it:
“The brain’s constantly worried about being poisoned.”
Though it’s a frustrating experience, motion sickness serves as a reminder of our evolutionary past and the incredible complexity of the human brain.
By understanding the science behind it, you’re better equipped to manage it—and maybe even appreciate the quirky mechanisms that keep us alive.
