Why do I get sick if I read in the car

A.� Motion sickness occurs when our sense of balance and equilibrium are disturbed. We naturally sense our spatial orientation: which way we are facing and moving, whether we are turning or standing still.

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When you read while moving you send confusing messages to your brain, making you feel sick. Your eyes, which are looking at a stationary page, rather than the moving scenery, tell your brain you're not moving. At the same time another sensory organ, your inner ear, picks up the motion of the car and tells your brain you are moving.

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Q.� How does our sense of balance and equilibrium work

A.� Via the interaction of the inner ears, eyes, skin, muscles and joints and central nervous system.

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The inner ear monitors the direction of motion, as do the eyes, along with keeping a check on where the body is in space.

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Pressure receptors in the skin, mainly on the feet and bottom, tell the brain which part of your body is down and touching the ground.

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The joints tell the brain which parts of your body are moving.

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Finally the brain and spinal column process all of the information from the four other systems to make some coordinated sense out of it all. Motion sickness starts when the brain receives conflicting messages.

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Q.� Why don't I get motion sickness windsurfing

A.� Because motion sickness tails off after a certain frequency of movement. The frequency most likely to cause sickness is 0.2 Hertz, and is comparable to a boat rolling every�five seconds. Anything above this frequency, like fast moving windsurfing, is less likely to make you feel sick.

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Q.� Why doesn't my baby appear to get car-sickness despite travelling backwards in her car seat

A.� Fortunately for some but not for others, not everyone is susceptible to motion sickness. Children under�two years rarely get motion sickness, but their susceptibility rapidly increases as they get older, peaking between 4 and 10 years, then gradually declines.

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Q.� How can I stop myself feeling sick when travelling

A.� Try to look out of the window to let your brain know that you really are moving. Always ride where your eyes perceive the same motion that your body senses, for example the front seat of a car, looking into the distance.

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Do you want to know why your body behaves differently in certain situations Click here to ask.

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by Lisa Cardy