Summary

Motion sickness is caused by a sensory mismatch between visual cues and the body's physical state, leading the brain to suspect poisoning and trigger nausea.

Abstract

The article discusses the neuroscientific basis of motion sickness, which is rooted in conflicting signals received by the brain. When an individual is in motion but their body is stationary, such as reading in a car, the thalamus and hypothalamus receive mixed signals from the eyes, inner ears, and muscles. This confusion can lead the brain to mistakenly assume the presence of neurotoxins, prompting a protective response to induce nausea and vomiting. The article suggests strategies like listening to music, eating a high-protein meal, or looking out the window to mitigate symptoms, although some individuals may naturally adapt or outgrow motion sickness.

Opinions

The author shares a personal anecdote about experiencing carsickness as a child and learning to avoid reading in the car.
There is a humorous tone in the discussion of the body's mechanisms and the author's coping strategies, including impersonations to distract from motion sickness.
The author expresses envy towards those who do not suffer from motion sickness and notes the randomness of this physiological quirk.
The author implies that drivers are typically immune to motion sickness unless they are in a self-driving car.
The article cites neuroscientist Dean Burnett, emphasizing the brain's conservative approach to unknown situations, which defaults to "be sick, just in case" as a protective measure against potential poisoning.

Neuroscience

Do You Want to Know What Causes Motion Sickness?

Your brain suspects poison because you’re moving but you’re not

I think I’m going to barf (Source: StockSnap on Pixabay)

Brain suspects foul play and resorts to triggering nausea.

As a kid I used to get carsick and Dad would pull over so I could do the full Monty. No brown paper bags as on airplane flights to capture my projections. (They use plastic bags now — not eco-friendly but safer.)

Why does reading make me sick?

I soon learned that the bile only arose when I was reading in the car.

So I stopped reading in the car. I’d look out the window at the people, buildings or countryside passing by, so Brain understood and took no remedial action.

But why is that?

Blame your thalamus

Our thalamus is one of those useful, yet at times illogical, rooms in the Brain’s mansion and is a sensory way-station which works in tandem with the hypothalamus.

(No, grammar purists, thalami, the Latin plural, is incorrect English unless you’re a math or science nerd)

The Hypothalamus is our home’s thermostat, regulating hunger, thirst, response to pain, levels of pleasure, sexual satisfaction, anger and aggressive behavior.

(All of which can occur in a car.)

In addition, it regulates our autonomic nervous system such as blood pressure, pulse, breathing, digestion, sweating and arousal in response to emotional circumstances.

Emotions are triggered by sensory awareness of our surroundings through our thalamus.

There’s the connection.

Except for our sense of smell, the thalamus receives what we see, touch, hear and taste.

The nose goes a different route.

But we’re fellow travelers in the same car. We’re sitting quietly doing nothing but something’s amiss. We’re moving.

But we’re feeling queasy.

Enter more villains

The silent partner deep inside our ears is those tiny little tubes of fluid, the motion of which tells us which way up we are: upside down, sideways, or upright — balance sensors.

When on the road, unless your car has top-of-the-range suspension and shock absorbers, this fluid sloshes around, telling us we’re moving.

But our muscles aren’t.

A third villain appears! The motor cortex gets in on the act and argues we are NOT moving.

Confusion creates catastrophe

Brain panics.

“Are we moving or not? I’m getting mixed signals.” `

There’s a sensory mismatch because our eyes and inner ears tell us we’re moving, but our muscles aren’t in motion.

And when Brain is unsure what the hell is going on, it concludes it must be neurotoxins or poison.

“Get rid of it!” is the order of the day.

Grab the brown bag.

Neuroscientist Dean Burnett from Cardiff University in the UK 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. And as a result, we get motion sickness because the brain’s constantly worried about being poisoned.”

It only happens to some of us

This quirk of our physiology — motion sickness — is random. I envy those who can read in a car, bus or train.

Many grow out of it. Perhaps Brain adapts.

(Drivers are immune unless it’s a self-driving car.)

These recommendations may help you:

listen to your favorite music
eat a light high-protein meal before departure.
look out the window so that Brain can be confident you ARE moving.

But I’m not taking any chances.

I won’t read on the road.

For distraction on a long trip, l do impersonations of Mrs Mills singing A Hard Day’s Night and other Beatles classics.

Then we must pull over because if I laugh any more, I’ll wet my pants.

A brown bag would be futile.

Thanks for reading!