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As the name implies, hallucinations are sensations that appear real but are mere creations of the human mind. It cannaffext the five humàn senses (Eyes, Nose, Ear, Tongue, and the Skin). The reason why someone may hear a voice no other person hears or taste what other consumer did not taste in a serves meal could be hallucination.
On the other hand. I really would to share the traditional perspective of the whole matter (hallucination). The African proverb "The evils that man does, lives with them" is many a times a reflection on an individual's mental state.
VISUAL HALLUCINATION
Majorly, seeing things that are not real is also an aspect of hallucination (visual hallucination).Some people maybe scared of taking their birth at night because a close relative had died and the feeling that the dead person may appear in the form of a spirit or ghost especially in the dark. And so such a person may avoid taking their birth at the night time.
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OLFACTORY HALLUCINATION
This to large extent involved the sense of smell. It may include scents one enjoys perceiving, like smell of fruits, flowers or perfumes. The victim may wake up at odd hours and suddenly begin to smell an unpleasant odor of even feel that one's body stinks when actually it doesn't.
GUSTATORY HALLUCINATION
This is similar to the olfactory hallucination but only involves the sense of taste instead of smell. Epilepsy I'd relatively a common symptom that occurs to people with this type of hallucination.image source
AUDITORY HALLUCINATION
Hearing someone speak to you, asking you to do certain things is one of the commonest hallucinations around. The voice may be neutral , warm, or angry. One may hear sounds like tiptoeing steps or tapping noises.
Generally speaking, this ailment is a disorder that temporarily disturbs the victim and makes him/her act in such an abnormal way.