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A story about the Nobel winning writer Isaac Bashevis-Singer has him resting at home after receiving news of his award. A reporter appears at his door:
"Mr. Bashevis-Singer, are you surprised? Are you happy?"
"Of course," answers the elderly writer, "I am very surprised and happy."
Ten minutes later, another reporter appears:
"Mr. Bashevis-Singer, are you surprised? Are you happy?"
"How long can a man remain surprised and happy?" comes the reply.
Along with the late writer's wit, this anecdote also illustrates the mechanism of habituation. Habituation, defined formally, refers to the fact that nervous system arousal decreases on repeated exposure to the same stimulus. In layman's terms, it means that familiar things get boring. This mechanism is hard-wired into the human genetic program. It has clear adaptive value, because habituation to familiar stimuli allows more energy to be directed to novel stimuli, hence improving the odds of survival.
Psychology has made several uses of this principle. For example, an infant can't report on whether they can tell the different between red and blue, or between "pah" and "bah" sounds. But you can habituate infants to one color or sound, and then switch to the other. If the infant dishabituates (shows physiological arousal), then you know they saw the difference. Marriage therapists will often advise a couple struggling with sexual boredom to "try something new." This works because a novel stimulus dishabituates the nervous system, causing arousal. That arousal can in turn be mined for satisfying sex.
But the most important application of the habituation principle has been in the area of anxiety treatment.
The experience of anxiety involves nervous system arousal. If your nervous system is not aroused, you cannot experience anxiety. Understandably, but unfortunately, most people attempt to cope with feelings of anxiety by avoiding situations or objects that elicit the feelings. Avoidance, however, prevents your nervous system from habituating. Therefore, avoidance guarantees that the feared object or situation will remain novel, and hence arousing, and hence anxiety provoking. Moreover, avoidance tends to generalize over time. If you avoid the elevator at work, you will soon begin to avoid all elevators, and then all buildings that house elevators, etcetera. Soon enough, you'll be living in a prison of avoidance.
Moreover, when you avoid something that scares you, you tend to experience a sense of failure. Every time you avoid a feared object or situation, your anxiety gains strength while you lose some; you accumulate another experience of failure and another piece of evidence attesting to your weakness. Finally, avoidance eliminates practice. Without practice, it is difficult to gain mastery. Without mastery, confidence is less likely to rise.
So, avoiding anxiety maintains and magnifies it. To get rid of your anxiety you should instead capitalize on the principle of habituation through the use of "exposure." Exposure is by far the most potent medicine known to psychology. It is responsible, directly or indirectly, for most positive improvement achieved in therapy—any therapy, but particularly the treatment of anxiety. Exposure entails facing your fears, which makes it aversive in the short-term. But many worthy long-term goals entail short-term discomfort (think studying for an exam).
Exposure also seems counter intuitive, but many truths are counter intuitive (think about the fact that we're residing on a ball floating in infinite space). Exposure scares people, but scary things are not necessarily dangerous (think roller coasters, horror films). Exposure is scary primarily because most people, lacking an understanding of the habituation principle, expect their fear to escalate indefinitely in the presence of a feared object or situation. But nothing rises indefinitely. And fear, if you face it, will soon begin to subside as you habituate.
Thus with anxiety, the only way out is through. If you're anxious about spiders, you will have to handle spiders. If you're scared of the elevator, you will have to ride the elevator repeatedly. If you dread talking in class, you will need to start talking in class. This is not easy to do, since confronting your fear will produce a lot of initial anxiety. You will have to stay in the feared situation and stay with the heightened fear response until it begins to subside, which it will, because it must by design.
Exposure works better than avoidance on the physiological level by bringing about nervous system habituation, which is the physiological antidote to anxiety. But it works better on three other levels as well.
On the psychological level, confronting your fear instead of backing down brings about a sense of accomplishment and empowerment. Every time you confront your fear, you gain power while your anxiety loses strength (I can tolerate it; it's difficult but not impossible; it's not the end of the world). Every time you confront your fear you accumulate evidence of your ability to cope (I did it yesterday; I can do it again today).
On the behavioral level, confronting your fear repeatedly helps develop skills and mastery. Mastery decreases the chance of failure and therefore reduces the need to worry.
Finally, exposure is particularly useful on the emotional level. It turns out that many (perhaps all) anxiety problems are at their core a "fear of fear." Most people who fear crowds, elevators, or planes know that these objects are not dangerous (they most likely let their kids go to the mall, ride the elevator, or fly in a plane). What they fear are the sensations of fear itself. Exposure to the sensations of fear allows them to habituate to these sensations, while at the same time improving their emotional literacy, since staying in the terrain helps to learn how to navigate, manage, and work it.
Exposure isn't easy. However, living in the prison of avoidance isn't easy either, and it isn't much of a life. The short-term discomfort of exposure is the price we must pay to purchase a valuable long-term asset—a life free from debilitating anxiety.
