Why Do We Experience Motion Sickness?
What is Motion Sickness?
Have you ever become sick or nauseous when reading in a moving vehicle? I’ve experienced it every time I am in the passenger seat or in the back seat. Something as simple as looking down to read a text message can cause me to feel nauseous. It has been something I’ve become accustomed to experiencing while in the passenger or back seat. Motion sickness has really impacted my ability to use my phone in a car, airplane, and even on roller coasters. In this post, we will discuss why this unpopular phenomenon occurs.
Did you know that about 20% to 30% of the general population is affected by some kind of dizziness? A study by Alyahya and colleagues (2016) describes motion sickness as having motion sensitivity that is stimulated by an abnormal spatial orientation. Common symptoms of motion sensitivity are feeling dizzy and having postural instability. Postural instability is the inability to maintain balance while standing or making any movements (Alyahya et al., 2016). The vestibular input is the sensory system responsible for keeping us balanced by detecting motion, spatial orientation, and our head position.
What does the research tell us?
Alyahya and colleagues (2016) studied the effects of vestibular adaptation exercises on posture stability in young and healthy subjects with chronic motion sensitivity. They recruited participants who experienced extreme motion sickness from activities such as reading in a moving vehicle while seated in the passenger seat, driving on winding roads, roller coasters, boats, and airplanes. The experimental group completed 6 weeks of vestibular adaptation exercises while the control group was told to avoid doing any new activities until the post-assessment date. What they found was that a minimal dosage of vestibular adaptation exercises actually improved postural stability in younger adults with chronic motion sensitivity (Alyahya et al., 2016). Vestibular-adapted exercises have been clinically proven to have a positive impact on motion sickness.
Why does it occur?
Koch and colleagues (2018) reviewed the current research on motion sickness and what interventions have been utilized to alleviate the symptoms. According to their study, motion sickness occurs as a result of an intersensory conflict between the vestibular, visual, and proprioceptive systems. This is called the sensory conflict theory. In their research they described why this conflict occurs:
Sensory Conflict Theory
Vestibular System
As we discussed previously, the vestibular system provides us with our sense of movement. It uses three semicircular canals located in the inner parts of our ear to provide our brain with information regarding angular acceleration and linear acceleration. Angular acceleration detects any rotational movements while linear acceleration detects movements in a straight line. All of these movements are made possible by the vestibular system functioning properly to provide our brains with awareness about how our bodies move through space (Koch et al., 2018)
Visual System:
The visual input is our sense of sight, observations, and making sense of the world using visual cues. It provides us with a frame of reference for where our body is based on the cues we receive from our environment. It helps us to navigate our environment by providing us with input about the body’s own motion. In a moving vehicle or airplane, it becomes challenging to distinguish between the motion of the body and the surrounding environment (Koch et al., 2018).
Proprioceptive System:
The proprioceptive input is our body's internal sense that tells us what we are doing, our actions and movement, and where our body is in space. We have proprioceptors located inside our joints and muscles that provide us with input about body position, location, and acceleration. Normally, our proprioceptive input provides complementary information about the position of the body in space with the rest of the systems. However, when the body is moving through space in a moving object, there is a sensory conflict that forms between the visual input, the vestibular input, and the proprioceptive input.
Motion sickness can be explained using the sensory conflict theory. This theory states that motion sickness is caused by a conflict between the three primary sensory inputs we receive. They are the vestibular, vision, and proprioceptive systems. When processed independently, these three systems work together to provide our brains with information about our body posture, movements, and motion through space (Koch et al., 2016)
6 Easy tips/tricks you can do to alleviate symptoms of motion sickness:
Avoid reading or looking down while in a moving vehicle, plane, or boat.
Focus on a distant object. If you are seated in the front seat, focus on the road ahead and the surrounding buildings. If you are in the back seat and have a panoramic sunroof, lay your seat back and focus on looking up at the sky.
Open the window if you can or have the air conditioner directed at your face.
Be aware of what you eat before getting in a car, plane, or boat. Avoid eating heavy meals, and sweet meals. Eat small amounts of food and drink lots of water!
Try chewing any minty/peppermint gum. Chewing gum can distract your sensory systems and divert the attention from the vestibular system being out of whack to the action of chewing in your mouth and the pleasant smell of the gum by your olfactory system.
Weighted blankets can also be helpful in grounding your body and providing it with a sense of balance when you are in a moving vehicle. You can wrap your body around the weighted blankets or have it laying on your lap on your next trip!
We hope you were able to find these tips helpful and learned more about motion sickness, and why it occurs! Let us know in the comments below if you’ve ever experienced this phenomenon.
References
Alyahya, D., Johnson, E. G., Daher, N. S., Gaikwad, S. B., Deshpande, S., Cordett, T. K., & Zidek, L. (2016). Effect of vestibular adaptation exercises on chronic motion sensitivity: a randomized controlled trial. Physical Therapy and Rehabilitation, 3(1), 1. https://doi.org/10.7243/2055-2386-3-1
Koch, A., Cascorbi, I., Westhofen, M., Dafotakis, M., Klapa, S., & Kuhtz-Buschbeck, J. P. (2018). The Neurophysiology and Treatment of Motion Sickness. Deutsches Arzteblatt international, 115(41), 687–696. https://doi-org.ezp1.lib.umn.edu/10.3238/arztebl.2018.0687
Photo 1- https://news.llu.edu/patient-care/car-sickness-driving-you-up-wall
Inner ear photo - https://www.mayoclinic.org/diseases-conditions/hearing-loss/multimedia/ear-infections/sls-20077144?s=5
Sensory conflict - https://scholarblogs.emory.edu/nbbparis/2019/06/17/motion-sick-ride-dude/
Diagram - http://thesexyscience.blogspot.com/2010/04/backseat-enemy-my-relationship-with.html
Weighted blanket - https://gravityblankets.com/blogs/blog/weighted-blankets-for-teens
Gum- https://www.oldtimecandy.com/products/spearmint-gum-pack
Panarmoic sunroof - https://www.kiacountryofcharleston.com/blog/pros-and-cons-of-panoramic-sunroof/