I've always had problems with heights, perhaps to an irrational degree. Growing up, we had a fold-down ladder that led from the garage to the attic, and for years, I hated climbing it. Once I got used to that, I found the courage to climb the big oak tree in our backyard -- until I fell out of it one day, smacking my head on a few branches on the way down and landing in a big pile of spiny plants. Ouch. I figured heights weren't for me and that was that, and for years I avoided them. Until recently, that is.
My wife joined a climbing gym, and I started to tag along. Then in New Zealand, I realized that my having any fun at all kind of depended on me facing this fear -- or at least managing it -- so that I could do the helicopter tours, small plane flights, paragliding, walks along rickety swing bridges and scenic drives up hair-raising, barrier-less switchbacks without having panic attacks. I succeeded to a degree -- here's proof -- and it got me wondering about acrophobia, the fear of heights, and what makes it tick. Here's some of what I learned.
Latching onto that early falling-out-of-tree episode, I grew up believing my fear was mostly associative. But I was wrong -- unlike most phobias, acrophobia is one of the few that's non-associative. Studies have shown that you're not conditioned to be afraid of heights; it's more of a hard-wired, Darwinian thing. An experiment called the "visual cliff" done on babies (creepy!) proved that even infants are wary of heights: when presented with a glass floor that had a clear view of a 10-foot drop beneath it, many infants, toddlers and young animals were reluctant to venture onto it.
So why the differences in people's experiences of acrophobia? Why can my wife climb a 30-foot wall with merely a rope attached to her waist while I get the willies at half that height? Researchers have wondered this too, and some have found that a person's balance is a key factor. It should surprise no one that people with balance disorders usually report a fear of heights, but it seems this is a two-way street; having a fear of heights may indicate that you have a balance disorder, if only a slight one. From Wikipedia's surprisingly adept entry on the subject:
The human balance system integrates proprioceptive, vestibular and nearby visual cues to reckon position and motion. As height increases visual cues recede and balance becomes poorer even in normal people. However most people respond by shifting to more reliance on the proprioceptive and vestibular branches of the equilibrium system. An acrophobic, on the other hand, continues to overrely on visual signals whether because of inadequate vestibular function or incorrect strategy. Locomotion at a high elevation requires more than normal visual processing. The visual cortex becomes overloaded resulting in confusion. Some proponents of the alternative view of acrophobia warn that it may be ill-advised to encourage acrophobics to expose themselves to height without first resolving the vestibular issues. Research is underway at several clinics.
This phenomenon, by the way, is totally distinct from that of vertigo, a rarer disorder in which sufferers experience acute dizziness triggered by certain visual stimuli (usually peeking over the edges of tall things). In any case, the idea that my fear of heights is related to my balance makes a lot of sense to me, because let's face it -- I'll never be a ballroom dancer. My balance sucks. My wife, on the other hand, does Pilates twice a week and spends a lot of time building up the strength in her core (ie, her center of balance), which must have something to do with it, and also -- crucially, I think -- she's pretty short, and I'm pretty tall.
Here comes my crazy hypothesis, and the reader response portion of the blog. I'm 6'3. My center of gravity is higher than most people's, and it's common knowledge that, as in the case of some high-set, flip-prone SUVs, it's harder to stay upright when your center of gravity is raised. (Ever see a low-rider flip over? It's hard to do.) By extension, doesn't it make sense that tall people are more likely to be afraid of heights than short people? I've certainly met more tall agoraphobics in my life than short ones, though it's my no means a rule. But answer me this:
Are you afraid of heights?
If so, do you feel your fear is tied to a particular traumatic event you experienced, or totally non-associative?
And finally -- how tall are you?