Phobia
A phobia is just like the regular everyday fears we all have, but on a much higher magnitude and strength. Also, it's an unreasoning fear. In other words, it's not one that's driven by logic. If you are about to be eaten by a bear and are afraid, that's logical; if you are afraid of a spider that's 15 feet away from you and not poisonous, that's not logical. A phobia is a fear that's out of proportion and interferes with your life. If you have a fear that never really keeps you from doing anything, it's not a phobia.
Phobias tend to get develop very quickly as a natural conditioned response just like the dogs who salivated in Pavlov's bell ringing experiment. Somebody gets scared of something and from then on, because of conditioning, they get that same physical and emotional fear response. People don't always remember where fears came from. Sometimes they do, but sometimes they don't. Often they will think they need to remember where fear came from in order to get over it, but that's not really the case.
Common phobias are the fear of public speaking, fear of spiders, fear of snakes, fear of flying, and social anxiety or agoraphobia. I deal with these all the time. There are certainly some factors that trigger them. Let's suppose that on two separate days, you watch two different movies. One day it's a comedy and one day it's a scary movie. If on both days somebody comes up behind you and says, "boo!" which one you are going to jump the highest on? Having a lot of stress or anxiety in your life can set the stage for creating a phobia. It's not the cause of the phobia, but it is a factor. Another factor could be the number of similar incidents that have happened to you in the past. Sometimes it takes two or three incidents to create a phobia.
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