Schizophrenia and Hallucinations
Most people are aware that schizophrenia is a mental health condition. One of the symptoms of schizophrenia is hallucinations. A hallucination occurs when the brain receives sensory information that is actually not there, meaning it does not exist. It is only a disturbance in perception created by the brain. Hallucinations can impact any of the five senses of a person, which means you can hear, feel, see, smell, or taste something that is not there and no one else can sense. (1,2,3)
Many people simply assume that hallucinations are a part of schizophrenia, and while it is true that many people with schizophrenia do have hallucinations, but it is estimated that only about 70 percent of people with schizophrenia have hallucinations. (4) However, schizophrenia is not always accompanied by hallucinations. You can also experience hallucinations for other reasons, and neither does having hallucinations automatically mean that you have schizophrenia. (5,6,7)
Let us look at some of the main features of hallucinations that occur with schizophrenia, what are the other reasons that cause them, and how they differ from other schizophrenia symptoms.
Hallucinations as a Symptom of Schizophrenia
Schizophrenia typically involves the symptoms of psychosis, which alters or disrupts the manner in which the brain processes information. (8,9) This can cause a disconnect from reality. There are primarily three main types of schizophrenia symptoms, including:
- Negative symptoms or a decline in emotions, thoughts, and behavior that you would generally have.
- Positive symptoms or the presence of feelings, perceptions, and behaviors that you would not generally have.
- Disorganized symptoms or disruption/confusion in your speech, thoughts, behavior, and even movements.
Hallucinations come under the category of positive schizophrenia symptoms, and they usually tend to involve any of the five senses, such as:
- Visual hallucinations mean the things you can see, such as distorted images, demons, or loved ones who are not there. (10,11)
- Auditory hallucinations refer to the things you hear, including voices, the ringing of a bell, and music. (12,13)
- Gustatory hallucinations that refer to things you can taste, such as something bitter or metallic on the tongue or in your throat. (14,15)
- Olfactory hallucinations that refer to things that you smell, including foul or sweet odors or something burning when there isn’t anything. (16,17)
- Tactile hallucinations that refer to things you feel, including the sensation of a hand on your shoulder, or many people feel something is slithering on your skin. (18)
Evidence has shown that auditory hallucinations are most likely to happen with schizophrenia. According to a recent research done in 2021, nearly 60 to 80 percent of people who have schizophrenia spectrum disorder tend to hear sounds that other people are not able to hear, including music, the voice of a loved one, or people conversing in a language that you don’t understand and recognize. (19)
Visual hallucinations are also known to occur with schizophrenia, though it is less common than auditory hallucinations. Research from 2010 shows that many people tend to see surreal things like distorted people, objects superimposed on other objects or on real people, distorted body parts, or just strange and unusual objects that they are unable to identify. Some people may also see things like demons, lights, or animals. (4)
Tactile, olfactory, and gustatory hallucinations are known to occur even less commonly. However, older research did find a strong link between these hallucinations, and the study showed that if you experience one type of hallucination, you are much more likely to experience the others as well. (6) You may even experience them as some of the early-stage symptoms of schizophrenia.
Experts have also found that hallucinations in schizophrenia can be multi-modal. This means that they may involve more than one of your senses. Evidence shows that multi-modal hallucinations are the most commonly experienced type in people with schizophrenia. A 2016 study that included data from 750 people who were diagnosed with schizophrenia spectrum found the following: (20)
- Nearly 80 percent of the study participants experienced some form of hallucination.
- Over 50 percent of the participants experienced multi-modal hallucinations.
- Nearly 27 percent of the participants experienced unimodal hallucinations or hallucinations that only involved one sense.
Is It Possible To Have Schizophrenia Without Hallucinations?
While many people living with schizophrenia tend to experience some type of hallucination at some point in their life, it is also possible to have schizophrenia without ever experiencing hallucinations.
To receive a diagnosis of schizophrenia, you must experience at least two of the five main symptoms on most days for a period of at least one month.
These main symptoms of schizophrenia include: (21,22,23,24)
- Confused or disorganized speech.
- Delusions
- Hallucinations
- Difficulty expressing emotions.
- Difficulty enjoying life or having an interest in life.
- Catatonia, or unusual or disorganized gestures and movements.
In order to get a diagnosis for schizophrenia, though, you need to have at least one of the two symptoms. One of these symptoms should be hallucinations, confused and disorganized speech, or delusions.
In other words, if you do not experience hallucinations, but you do experience delusions along with other symptoms of schizophrenia, you might have schizophrenia.
Are Delusions the Same as Hallucinations?
Delusions also show a disconnect from reality, but delusions only involve thoughts, and there are no sensory perceptions. Experiencing a delusion means that you have a certain belief that is not true or real. This belief may appear completely real to you, and therefore you hold onto it. However, you have no proof that supports it, and other people may even offer evidence that counters it. Examples of delusions may include:
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Somatic Delusions: These types of delusions involve a strong belief that there is something wrong with your health or body. You may believe that certain parts of your body are misshapen or that there is something growing inside your organs. (25)
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Persecutory Delusions: These types of delusions, also known as paranoia, involve having a strong suspicion of others. You may firmly believe that people want to harm or steal from you or that they are conspiring against you. (26)
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Grandiose Delusions: Also known as delusions of grandeur, these types of delusions involve having a belief that you have some type of special and unique ability, talent, connection with a celebrity, or a religious deity. (27)
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Erotomanic Delusions: These types of delusions revolve around a belief that someone else, usually someone famous, is in love with you.
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Religious Delusions: These delusions involve having a belief that you are a deity or god or that someone has selected you to act for them to carry out their desires. (28)
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Thought Insertion and Withdrawal Delusions: Having such types of delusions mean that you believe there is some outside source that has inserted some thoughts into your brain or removed your thoughts.
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Control Delusions: Control delusions involve having a belief that some outside force or entity has control over your feelings, behavior, or thoughts.
It is also possible for hallucinations and delusions to occur together. For example, you may believe that you have the ability to communicate with the dead, mainly because you often hear voices that you believe belong to people who are deceased. Or you may even think that there is some type of parasite living under your skin. You may feel prickling and itching and even see your skin being ripped open or bulging out, even though people around you assure you nothing appears different.
What Causes Hallucinations in Schizophrenia?
Experts are not very sure about why hallucinations happen, be it with schizophrenia or with any other health condition. Some theories typically associate them with the spontaneous activation in some parts of the brain. These spontaneous activations are believed to trigger the sensory details that are linked with the hallucination, including the images, sensations, or sounds that no one else notices. (29)
On the other hand, brain imaging studies have shown that people with schizophrenia have an increased activity in some parts of the brain, especially the paralimbic and hypothalamus regions, as well as decreased activity in other parts like the temporal lobes. (30)
Experts have also found that people living with conditions that involve symptoms of psychosis have decreased gray matter in parts of the brain. (31)
The neurotransmitter dopamine is also believed to play an important part as evidence has linked the positive symptoms of psychosis, such as hallucinations, to high levels of dopamine in the mesolimbic pathway. This pathway is known to play an important role in the brain’s reward system. A study from 2019 found imbalances in the levels of dopamine within the nigrostriatal pathway. (32)
Hallucinations are, therefore, believed to be related to irregularities in brain structure, chemistry, and processing. However, hallucinations are much more common than most people would think.
In fact, it is possible to have hallucinations with any of the following conditions:
- Bipolar disorder
- Extreme stress or grief
- Postpartum psychosis
- Major depression with psychotic features
- Migraine
- Seizures
- A high fever
- Sleep deprivation
- Vision loss
- Hearing loss
- Progressive neurological conditions like Alzheimer’s disease and Parkinson’s disease
Of course, hallucinogenic drugs can also cause hallucinations, but similarly, there are some other substances also that can cause hallucinations. For example, a 2012 study found that people experience hallucinations after drinking heavily or when going through alcohol withdrawal. (33)
A less common reason behind hallucinations can be due to a side effect of some medications, including medicines that are used in the treatment of:
- Depression
- Psychosis
- Parkinson’s disease
- Epilepsy
Conclusion: Is There Any Treatment For Hallucinations?
If you experience any form of hallucinations, it is important to get professional help. You might not feel the need to treat hallucinations that occur rarely and that don’t both you, like the sense of a comforting presence or a faint sound of music, but it is still necessary to get professional help.
Schizophrenia does not get better without proper treatment, and hallucinations can also happen as a symptom of another underlying condition. A doctor can help identify the possible causes of your hallpucinations and also offer proper guidance on what will be the best course of treatment for your individual condition.
As there is a lot of stigmas, myths, and misunderstanding surrounding mental health conditions that involve hallucinations, you may hesitate to seek support and treatment.
However, keep in mind that a good therapist can offer you the support you seek and also help alleviate your symptoms and the possible triggers or causes. Remember that while treatment might not make your hallucinations disappear completely, both medication and therapy can make a huge difference in the quality of your life.
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