Hallucinations – It may be a symptom or sign of a mental health illness and can occur any time when there is a change in brain activity as many individuals are more vulnerable to hallucinations if they are falling asleep or partially walking. It is also a false or wrong perception of events or objects that involve all five senses such as taste, smell sound, touch, and sight.  Several hallucinations are normal and are caused by partial waking up or falling asleep. However, many hallucinations may be a symptom or sign of more serious conditions such as dementia or schizophrenia. It is important to note that abnormalities or chemical reactions in the brain may cause hallucinations. Hallucinations are also sensory feelings or experiences, which appear real but are created by the mind. 

Types of hallucinations – There are several types of hallucinations are given below -

1. Visual (sight) hallucinations – This type of hallucination may involve seeing things that are not real such as shapes, lights, objects, animals, or people.
2. Auditory (sound) hallucinations – It is one of the most common types of hallucinations that involve hearing sounds that are not real such as door banging, music, or footsteps. Several individuals hear voices if no one has spoken at that place and these voices may be neutral, positive, and negative. Many persons may cause harm to yourself or others.
3. Olfactory hallucinations – This type of hallucination may involve the sense of smell or experiences different smells but that no one else can smell.
4. Gustatory (taste) hallucinations – This type of hallucination may cause testes which are often unpleasant or strange. Gustatory hallucinations are relatively common signs or symptoms for those individuals who are suffering from epilepsy.
5. Proprioceptive hallucinations – This type of hallucination makes you feel that your body is moving like floating or flying which is not real.
6. Tactile (touch) hallucinations – This type of hallucination may cause that you to feel any movement in your body or feel touch on your body which is not real. It may involve feeling like your organs are moving around or bugs are crawling on your skin which are not real.
7. Presence hallucinations – This type of hallucination makes you feel that somebody is in your room with you or standing or sitting behind you which is not real.
8. Hypnagogic hallucinations – This type of hallucination may occur when you are sleeping. During sleeping, generally, you see moving patterns and vivid images or shapes of animals, scenes, or faces, which are not real.
9. Hypnopompic hallucinations – This type of hallucination may happen when you are waking up from sleep. Hypnopompic hallucinations are normal and may not be harmful to individuals. It may be more common in those individuals who are suffering from sleep disorders.