All psychiatric disorders consist of normal behavior taken to an extreme for one reason or another.
Dragonfire is correct. It is easy for the public to see a few features and conclude that they or others have a full-blown disorder or to use a
feature of a disorder to label someone else for malicious purposes.
OCD is one that is commonly abuse in this way as is Bipolar.
I hear kids calling their parents Bipolar, when what they mean is that when they smash the family car, get caught with drug, get pregnant, or submit a
failing report card their parents become angry and agitated.
So, normal people do hallucinate under the right conditions. Others might become convinced that they are conspired against or become obsessed with
something or someone and a host of other feature of disorders, but when these conditions are transient or are normal reactions to environmental cues,
then they are not necessarily pathological.
Stay up for four days straight and see if you don't begin to hallucinate. Make the members of your social clique angry and see if you don't begin
to see conspiracies all around. Buy a new video game or meet an attractive member of the opposite sex and see if you don't become obsessed.
Even for clinicians the use of diagnostic terms can be troublesome. Clinicians are warned very early on in their training that it is better to
describe discrete behavior than to use diagnostic categories until such time as enough evidence is gathered to make a definitive diagnosis.
Here's a good example of behavior that could easily be called OCD. However, I bet that this mailman either has never lost a piece of mail or he has
not lost one in a very long time and that one incident engendered this behavior.
As long as this guy gets his mail on time and doesn't lose it, he'll probably be looked upon as a very efficient employee.
However, when he retires and this behavior ceases to have a function, he might find that he can never get anything done at all, because he can't stop
checking to make sure everything is perfect.
Then, if his behavior comes to the attention of clinicians, he'll likely get a diagnosis, some meds and some kind of therapy.
[edit on 2008/6/28 by GradyPhilpott]