Hallucinations: Causes and Types
Most of us pretend themselves 100% perfect to the world but be sure that humans can never be 100% perfect. Exactly! Sometimes humans believe in many unreal things that do not exist in real life, but our brain is deceiving us. Hallucinations are such feelings and emotions that have no existence. Just like you are focusing on a single point in a picture and stop viewing it for a minute or two. You feel like everything around you are moving; that, in fact, is not the reality. Studies report hallucinations in approximately 6-15% of the United States population.
Highlights
- Hallucinations are such feelings and emotions that have no existence in reality. Hallucinations are when you mistakenly believe that something you see, hear, smell, touch, or taste actually exists.
- Hallucinations have a relation with the human psyche. So, conditions that disturb the human psyche and result in hallucinations include Alzheimer’s and Parkinson’s disease, schizophrenia, alcohol and cocaine abuse etc.
- Doctors prescribe antipsychotic drugs and acetylcholinesterase inhibitors and suggest repetitive transcranial stimulation to people with hallucinations.
What are hallucinations?
You have a hallucination when you mistakenly believe that something you see, hear, smell, touch, or taste actually exists. Hallucinations are false perceptions that can fool you. Abnormalities and chemical reactions in the brain bring on hallucinations (Figure 1). Psychotic disorders, such as schizophrenia, often feature hallucinations as one of their symptoms, but drug side effects, neurological disorders, and certain temporary situations can also bring on similar experiences. A hallucination can occur with or without the awareness that the experience is not real. A psychotic symptom is a belief that a hallucination is real.
Types of hallucination
Hallucinations can be of many types. Following are a few common types of hallucinations:
Auditory or sound hallucinations:
The most common form of hallucination involves sound distortions. Auditory hallucinations include the perception of fictitious music, footsteps, or door slamming. Some individuals hear voices even when there has been no communication. These voices may be positive, negative, or agnostic sentiments. Something they tell you to do could endanger you or others.
Visual or sight hallucinations:
They refer to the experience of seeing images that are not actually present, such as false people, animals, or objects.
Tactile or touch hallucinations:
They involve a false perception of physical contact or motion. For example, the sensation of bugs crawling on your skin or shifting internal organs.
Olfactory or smell hallucinations:
In this case, a person perceives odors that do not actually exist or that no one else can smell.
Gustatory or taste hallucinations:
The hallucinations of gustation or taste typically result in an unusual or unpleasant sensation in the mouth. Many people with epilepsy report gustatory hallucinations, most commonly involving a metallic taste.
Presence hallucinations:
If you feel like someone is physically in the room with you or behind you, you still can’t see them.
Proprioceptive or thought hallucinations:
trick the brain into thinking that the body is in motion when it is not.
Besides hallucinations of sensory organs, someone may also have sleep-related hallucinations. A few examples are given below:
Hypnopompic hallucinations:
It happens when a person is just waking up from sleep. Certain sleep disorders may increase the risk for hypnopompic hallucinations, although
Hypnagogic hallucinations:
These are hallucinations that you experience as you fall asleep. Their duration is brief, and the majority (86%) are visual. People frequently perceive shifting shapes and patterns and clear, distinct images of people, animals, and other scenes. There is usually no need to worry when this kind of hallucination occurs.
Difference between hallucinations, illusions and delusions
Hallucinations involve sensory perceptions such as hearing, seeing, tasting, smelling etc. Illusions involve misinterpreting a real object, person, thing etc. When comparing hallucinations and illusions with delusion, they are unshakeable beliefs in something unreal or untrue.
Causes of hallucinations
After glancing at the scientific background of hallucinations, hallucinations can have multiple causes. However, they are more related to the human psyche. Conditions that disturb the human psyche and result in hallucinations include:
Temporary causes
Alcohol or cocaine addiction, severe dehydration, migraine, trauma, grieving, and recovery from anesthesia.
Mental health conditions
Schizophrenia is a common mental health condition that causes hallucinations. It can be a single or multiple mental health conditions that causes psychosis-related disorders. Psychosis is when a person experiences a kind of disconnection from reality.
Neurological conditions
Parkinson’s disease and Alzheimer’s are the best examples of neurological conditions that can cause hallucinations. About 20-40% of people with Parkinson’s disease experience delusions or hallucinations. In contrast, 13% of Alzheimer’s patients experience hallucinations. Other neurological conditions that can cause hallucinations include epilepsy, Lewy body dementia, narcolepsy etc.
Treatment
Because hallucinations disturb the human psyche, doctors prescribe first- and second-generation antipsychotic drugs to treat them. These drugs decrease the severity of hallucinations resulting from schizophrenia. Acetylcholinesterase inhibitors block the normal breakdown of neurotransmitters “acetylcholine” in Alzheimer’s and Parkinson’s patients. Some patients with auditory hallucinations do not respond well to antipsychotic drugs. Thus, doctors suggest repetitive transcranial stimulation (rTMS).
