There are many things that people sometimes claim they “see” that really aren’t there. They may have visions of “ghosts” or strange creatures. Sometimes little children claim they “saw” things that no one else did. Sometimes these are fantasies or day dreams; sometimes they are illusions.

There is a difference between an illusion and an hallucination. When a person has an illusion, there is something present that stimulates the eyes or senses. It can be verified, because other people see it, too. A mirage, for example, is a kind of illusion. But the main point is that something is there that causes the person to think he saw what he saw.

When a person has a hallucination, however, nothing is there! There is no outside stimulation to the eyes or the senses. The only stimulation comes from the person himself, from his own fantasy.

Hallucinations can be of various types, relating to the various senses. The most common have to do with hearing. A person imagines he hears voices, mutterings, laughter, cries, bells ringing, music playing or even shots ringing out! The second most common type of hallucination has to do with seeing. People imagine they see certain persons who aren’t there, or they may see animals, objects, or whole scenes before them. Sometimes they “see” strange, horrible, and unearthly things that terrify them. And sometimes people even have hallucinations about tastes and smells, or things they feel on their skin!

There are many reasons why people have hallucinations. One of the most common is that a person is very troubled and disturbed by something. If someone has been aroused emotionally to a high pitch, perhaps very angry or frightened, he may have hallucinations.

In other words, persons who are hallucinating are usually in a state of great excitement, fear, ecstasy, or anticipation of something. Certain drugs also cause hallucinations. Cocaine, for example, gives the hallucination of insects crawling on the skin!