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**Why I Can’t Read in Cars – And How an iPhone Feature Might Help**
I can’t read in cars. Listening to music is fine, as are podcasts and audiobooks, but anything that requires looking down at a page or screen for longer than a few moments leaves me feeling nauseous.
I was intrigued, then, when I stumbled on an iPhone feature that’s supposed to prevent, or at least reduce, carsickness. The feature is called **Vehicle Motion Cues**, and it overlays dots on the left and right side of your screen. Those dots move as the vehicle you’re riding does things like turn or speed up.
### How Is This Supposed to Work?
To answer that, we need to talk a bit about what causes car sickness in the first place.
#### How Motion Sickness Happens
As we’ve reported before, there are two common theories for motion sickness: the “postural instability theory” and the “sensory conflict theory.”
– **Postural Instability Theory:** This theory suggests that when humans lose control of their posture—on a rocky boat, say, or a roller coaster—we get sick.
– **Sensory Conflict Theory:** More commonly cited in medical research, this theory proposes that motion sickness happens when the movement you see is different from what your inner ear senses. This is the explanation favored by the Centers for Disease Control and Prevention (CDC) and the theory Apple’s Vehicle Motion Cues is built around.
#### The Role of Your Inner Ear
But what does your ear have to do with anything?
It turns out your ear does more than just hearing. The **vestibular system**, which is part of the inner ear, is basically why you can do things like run or ride a bike without falling. According to the Cleveland Clinic, a fluid called **endolymph** sloshes around in your inner ear. The movement of this fluid is detected by tiny hair cells within the system, and this detection helps you “feel” that you’re moving, even when your eyes are closed.
Your vestibular system works closely with your visual system to maintain balance. This works great when you’re moving under your own power—walking, running, or biking. The problem arises when you’re moving in a vehicle that you don’t control.
If you look away from the horizon, your body senses movement but your eyes don’t see it. This conflict between what you feel and what you see causes the sensory conflict that leads to nausea and motion sickness.
This is why the Cleveland Clinic recommends that anyone who feels motion sickness while reading should put their “book, phone or tablet away and look at objects in the distance or the horizon” to resolve this conflict.
#### Additional Tips to Reduce Motion Sickness:
– Eat well before a trip; traveling on an empty stomach doesn’t help.
– Avoid alcohol and smoking, as both can worsen carsickness.
### So, What’s Apple’s Vehicle Motion Cues Feature?
Back to your iPhone. The **Vehicle Motion Cues** feature is found in **System Preferences > Accessibility > Motion**. It places circles on both sides of your display that move in sync with the vehicle’s movements.
You can set these circles to appear all the time or only when your iPhone detects you’re in a vehicle.
Here’s how the circles behave:
– When the car moves forward, the circles “pass” alongside what you’re reading at the same speed as objects outside the window.
– When the vehicle reverses, the circles move in the opposite direction.
– When the car turns, the circles move in a way that suggests that turn is happening.
The idea is that these circles provide a visual cue to reduce the sensory conflict between your eyes and your inner ear.
### Is There Any Research Behind This?
Apple’s release about the feature doesn’t cite any specific scientific study, but a 2019 paper from researchers at the University of Salzburg used a very similar approach. Their Android app displayed moving bubbles on the side of the screen that reacted like Apple’s dots. Most participants reported reduced feelings of motion sickness, though the study was small-scale.
Since Apple’s feature has only been available for about a year, there isn’t much research on its effectiveness specifically.
### User Experiences and Final Thoughts
Some users report great success with the feature, though it doesn’t work for everyone. Anecdotally, I tried it while running errands and found myself feeling a little less sick with the feature enabled.
If you find yourself feeling nauseous in the car while reading, research suggests it might be worth a shot. You can toggle the feature to activate only when you’re in a moving vehicle and see how it affects you.
You might just find yourself capable of reading in the car after all.
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https://www.popsci.com/diy/vehicle-motion-cues-iphone-carsickness/