Biology 103
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I know that my sometimes paralyzing fear of spiders is not rational. I am logical enough to even feel a little silly about it. But I am merely one of the four-five percent of the United States' population that suffers from specific phobias (1).

A phobia is an irrational fear triggered by certain objects or situations. There are three types of phobias- specific, social and agoraphobia (2). Specific phobia is the fear of a specific object or thing. My fear of spiders (Arachnophobia) would fall under this category, along with Acrophobia (fear of heights), another common phobia (3). The second category of phobia, social phobia, is the fear of social situations. And the last category of phobia is Agoraphobia, the fear of any situation that might provoke panic attacks, or fear of losing control. Agoraphobia is often accompanied by panic disorder (2).

All three types of phobias create a physiological response in their sufferers. When someone encounters her phobia, she will experience what is known as the "fight-or-flight response". An increase in adrenaline causes one's heart and breathing to accelerate, muscles tighten and sweat glands to activate, it also triggers a release of stored sugar, increased metabolic rate and inhibited digestion. The "fight-or-flight response" is activated when one feels threatened and is a sort of biological safety mechanism. With phobias, however, this response is irrational and does not serve its original biological purpose- to keep humans aware and able to cope with dangerous situations (4). While it may have made sense for me to have this sort of reaction to spiders if I was living thousands of years ago, nowadays it makes my life more difficult.

Although scientists are not sure as to exactly what causes phobias, many believe that they are caused by a combination of environmental and genetic factors. Phobia can be caused by a traumatic event- if someone almost drowns then they may develop a fear of water. Phobia may also be in part genetic- studies show that twins tend to have the same phobias (5).

An interesting theory is that humans are "biologically prone" to having certain kinds of phobias, such as the fear of snakes, spiders or other potentially poisonous creatures, because those fears may have been crucial to the survival of humans long ago and they remain in our brains to this day (5). Yet this would only explain certain kinds of specific phobias, and not social phobia or Agoraphobia.

Some therapists believe that phobias are learned, and can therefore be unlearned. This theory is the basis for some treatment in which one is gradually exposed to the thing that she fears, forcing her to confront the fear and recognize that it is, in fact, not rational. With the invention of virtual reality, this type of therapy has become easier, because one does not have to actually ever leave the room to experience her phobia. It is not clear, however, whether this is as effective.

Another way of treating phobias and other Anxiety disorders is to take medication. Seratonin re-uptake inhibitors such as Paxil or Luvox, which can also be used to treat clinical depression, are sometimes effective in curbing Anxiety disorders. Benzodiazepines are another class of drug which are specifically oriented towards preventing anxiety and panic attacks (6).

Most people, like me, just choose to live with their phobias. I just avoid spiders like the plague. And I have been able to get to the point where I am not paralyzed by them anymore- now I can actually approach them…but only to kill them, of course. I do go to somewhat extreme measures to destroy any spider I see (dragging a ladder up three floors at 3 am to reach one on the ceiling…) but this doesn't seem like something I need to seek treatment for.

But studying phobias has raised several questions in my mind. For instance, if phobias are, at least in part, a hold over from thousands of years ago, why haven't they disappeared yet? If we can adapt to have phobias to keep us away from danger, can't we adapt to not have phobias? Or are phobias just a complication that comes along with having a complex biological system, and therefore complex defense mechanisms?

Another interesting idea is that phobias seem to demonstrate the connection between emotions and the body. One experiences an emotion and then has a physiological response- or is it the other way around? In any case, could understanding phobias be a gateway to understanding this mind-body connection further?

For the time being, however, I will just avoid sites with big, hairy wolf spiders on them…

WWW Sources

2)National Institute of Mental Health online,Anxiety disorders page

3)The Phobia List,alphabetical listing of most phobias

4)Health World Online

5)Cyro Masci, MD

6)PsyWeb.com,page on Specific Phobias

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