Imagine that it’s a beautiful day for a sail. There’s a friendly breeze, the temperature is ideal and the water is so inviting. Let’s go!

You’ve been out for an hour or so, snoozing on the sun-drenched deck enjoying a gentle roll from side to side. Now, the wind begins to shift and become brisk. It’s getting chilly, and you go below for comfort. The boat begins to roll and pitch more, and suddenly, you feel a bit uneasy in your stomach. In fact, you’re feeling nauseated, and before you know it, you really need to throw up whatever is in your stomach.

What is this?

This is called seasickness or motion sickness or, more technically, kinetosis. This comes from Greek, implying a pathological condition (-osis) related to movement (kine-). And the concept of seasickness comes directly from the Greek word nautia, from which we get the word nausea.

It can happen on a boat, but it can just as well happen on an airplane, a train, in your car, and even while going to the movies or playing video games. Some are more prone to this than others. I, for example, seem to have a penchant for motion discomfort when there is a certain kind of roll to the vehicle I’m in.

How can this happen? Going pretty quickly from dreamy comfort to uncontrollable sickness seems unlikely, but it happens often. A good third of us can get some motion sickness on a boat even in calm waters. And two-thirds of us are susceptible under more severe conditions.

What’s happening in your body?

Simply stated: Your eyes and your ears are reporting conflicting messages with the result that your brain decides it needs to rid your body of potentially harmful contents.

First, you need to know that in addition to hearing, your ears also contain what you need for staying balanced, your sense of equilibrium. It’s called the vestibular system, and it has to do with the motion of fluid in three semicircular canals in each ear.

Second, although your eyes are primarily for seeing, your visual system is intricately interconnected with your vestibular system. And this is the connection that gets disrupted in motion sickness.

There are three situations that cause kinetosis:

You feel motion, but what your eyes see is stable. This happens, for example, when you are in a boat cabin that appears stable, but you feel the boat rocking. It could also be in a car whose motion you feel, but the map you’re trying to read appears stable.

You see motion, but have no feeling of it. This can happen in an IMAX or other theater where the motion on the screen is realistic, but your seat is firm and not moving. The same effect may be had with virtual reality situations like a flight or driving simulator.

You both see and feel motion, but the sight and movement don’t make sense together. This can happen when you’re riding in a slow-moving car on a very bad road. You are constantly feeling the bumping up and down or jerked to the side from potholes, but because of the slow speed, your eyes fail to perceive the same movement.

There are a few competing thoughts about how motion sickness comes about, but the most popular one alleges that motion sickness is a defense against neurotoxins. A part of your brain is called the area postrema, and its function is both to induce vomiting if there are poisons in your system and to resolve conflicts between your visual and vestibular systems.

Here’s the way it works:

Let’s say you are in a ship’s hold with no windows. Your vestibular system sends signals to your brain that there is motion, but your visual system sends signals that there is no motion. As a result, your brain concludes that you are hallucinating because of having ingested some poison. Your brain then sends signals to the area postrema to vomit, thus clearing out the poison.

Other thoughts about this include a similar mechanism, but without the need to posit a poison.

How to avoid motion sickness

There are head-worn computer devices with a transparent screen that give you digital reference lines that show the position of the horizon relative to your head. Some claim that these are effective, as may be just staring at the horizon.

There are over-the-counter medications like Dramamine or the antiemetic Bonine that have some effect, as well. You can get also a medicated patch for motion sickness or an acupressure bracelet.

Surely, there are simpler and cheaper ways than these. One effective counter to car sickness seems to be chewing gum or something else, although no one seems to know why this works. Next, I suggest that before going on a transport that’s likely to be rough, consider not eating anything for several hours before departing.

When discomfort starts

When you begin to feel some discomfort, disconnect your eyes from your ears. This is best done by lying down or reclining with your eyes closed. It can be done in a car or airplane or boat. This allows your sense of balance to enjoy the motion without any conflict from your visual system.

My wife, Clare, and I embarked on a particularly rough ferry crossing of the English Channel. Fortunately, I had the foresight to engage a cabin with two bunks. While others, including crew members, were seasick, we spent the entire trip snoozing comfortably on our bunks enjoying the ride. Admittedly, we did feel a bit queasy whenever we had to get up.

You can also use a do-it-yourself acupressure technique. Hold your left hand in front of you with the palm toward you and your fingers pointing upward. Now, place the first three fingers of your right hand across your left wrist immediately below your left hand. Immediately below your right index finger on your left wrist, notice a hollow point between two tendons.

In acupressure, this point is called P6, or pericardium 6, and is known for relieving the symptoms of kinetosis. Now, use the fingers of your right hand to rub the P6 point for two to three minutes, and repeat the process for your other wrist.

We’re not alone

As it happens, we humans are not alone in this. Dr. Reinhold Hilbig, a zoologist from Stuttgart, Germany, determined that in a situation of loss of eye contact with water movement, even fish get seasick!


With motion sickness and other conditions, being aware of the circumstances that cause it can help you take preventive action before you get sick. Even before you start to feel sick, being aware that your vestibular and visual systems are having different experiences can stimulate you to make changes to your situation. 

Bob Keller maintains a holistic practice in Newburyport. He offers medical massage therapy for pain relief, as well as psychological counseling, dream work and spiritual direction. Many patients call him Dr. Bob and accuse him of doing miracles, but he is not a medical doctor nor a divinity. His expertise is medical massage therapy, understanding this miracle we call the human being. He can be reached at 978-465-5111 or

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