Tiny tots think it’s great fun to whirl around until they lose balance and fall down. And if we’re honest, most of us have felt the room spin when we’ve gone to bed after too much booze.
I was travelling down from the 10th floor of my office building in the Hit when l bent over to fasten my shoelace. I was suddenly dizzy and disoriented and had to kneel down to stop myself falling over. I never have any difficulties travelling in lifts, but presumably this was in some. way caused by the. fact that I was descending. I tried it again a week later with. much the same effect. Why does bending over in a descending lift make me dizzy?
It is not uncommon to feel dizzy in a lift. This is a symptom of motion sickness and occurs when the brain gets conflicting messages from the systems regulating balance and spatial orientation: vision, the vestibular system in the inner ears, and the proprioceptive system of receptors in' the muscles and joints.
The vestibular system comprises the otolithic organs, which detect linear acceleration, and the semicircular canals, which detect rotational movements — pitch, roll and yaw.
When you stand in a descending lift, there is a conflict between vision and the otolithic organs. This is enough to disorient some people and cause motion sickness. If a person bends over, there is also conflict between vision and the semi-circular canals. To the semicircular canals, the act of bending is exaggerated by the lift’s descent, which is not detected visually. This is like walking towards the prow of a ship along an internal corridor as the ship pitches into a trough. This could have been your tipping point (in more ways than one) into mild motion sickness.
If you were to bend over in the descending lift and, at the same time, shake your head from side to side, it would induce aspects of roll and possibly yaw, depending on how far you were to bend. This would cause further disorientation and increase the likelihood of you landing on your head.
What is the Vestibular System?
The vestibular system includes the parts of the inner ear (the organs of balance), the pathways that lead to the brain, and the brain itself that help control balance and eye movements. If the system is damaged by disease, aging, or injury, vestibular disorders or balance difficulties can result.
Why do my legs become wobbly when I stand near a cliff top?
These effects vary from person to person. My wife, who is not acrophobic, gets a tingly feeling in her palms and soles, presumably in anticipation of a need to cling on with all the passion of her simian ancestors. If however, like me, you have a poor sense of balance, and rely on visual input to supplement it, I speculate that this feeling is an effect of poor feedback. Normally one sways according to the balancing movements of the legs and unconsciously adjusts according to one’s vision. Standing on a cliff where no level ground or rising walls offer visual clues to help you avoid toppling, your legs get poor feedback and keep over-correcting. That feels very insecure, which could set knees shaking.
When fear causes legs to tremble, the impulse seems a primitive one: small children and many other immature animals commonly throw themselves to the ground when frightened, in a state of helpless submission. Shaky legs might be part of that response.
A wry saying in Afrikaans expresses defiance of the symptom: ’Staan stil broek; jou baas is nie bang nie’, which translates into English as ’Stand still trousers; your master isn’t afraid.’