Vertigo is the leading cause of dizziness.
People who suffer vertigo feel a sense of movement, even if they are sitting still.
It can be incredibly uncomfortable and can result in nausea and vomiting.
The symptoms are often made worse by actual movement of the head.
Vertigo is more common in the general population than once thought, affecting more than 5% of the adult population. It can result not only in dizziness but also an interruption in daily activity and sometimes sick leave.
Migraine, hypertension, stroke and hyperlipidaemia have been associated with vertigo.
Central vertigo occurs when injury to the balance centers of the central nervous system occur.
Peripheral vertigo, however, is caused by problems with the vestibular system. This is the sensory system that lies within our inner ear and is responsible for our sense of balance and spatial orientation.
Our sensation of motion arises in the semicircular canals within the vestibular system. A series of small tubes detect motion through the movement of internally contained fluid against microscopic hair-like nerves endings that line the canal’s inner surfaces.
Home Science Demonstration:
Step 1: Take a seat on a swivel office chair.
While you are resting there, the fluid-filled tubes and their micro nerve endings are at rest too.
Step 2: Use your feet, on the ground, to slowly turn the chair around.
The liquid in the tubes is beginning to move too, triggering the nerve endings to communicate to your brain – recognizing and interpreting your body’s movement.
Step 3: Now, spin a little faster.
The fluid is picking up speed and momentum, sending more information to your brain. Your brain is telling your eyes that you are moving, so they instinctively begin to shift, attempting to focus ahead, constantly re-adjusting.
Step 4: In one rapid movement, plant your feet on the ground firmly and stop the chair from spinning.
Due to the inertia, the movement of the fluid within the tubes will continue to move. The nerve endings will continue to be stimulated to send information to your brain. Your brain thinks you are still moving even though you know you’re not.
There is a clash of information. You are officially dizzy.
Your eyes are probably darting backwards and forwards without you knowing it. This is an involuntary reflex action called vestibular nystagmus. Your brain is telling your eyes that you are still moving. This is a common sign in a patient experiencing vertigo. A clear sign that there is an information clash.
Imagine feeling like that suddenly, even after sitting still, on a stationary chair?
Home Science Experiment:
Turn this Demonstration into your own dizzy Experiment by timing how long you spin versus how long it takes you to recover.
Alter the spinning times and observe the difference in recovery times.
Have a mate join you and see if their recovery time varies from your own.
Try closing your eyes when you spin, does this make a difference to your recovery signs and times?