What Are Delusions?

Table of Contents
View All
Table of Contents

A delusion is a strongly-held or fixed false belief that conflicts with reality. The Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) defines delusions as fixed beliefs that are not amenable to change in light of conflicting evidence.

Delusions are a common symptom of psychotic disorders such as schizophrenia, delusional disorder, and schizoaffective disorder. They can also be present in other psychiatric disorders, including major depressive disorder with psychotic features and mania in bipolar disorder.

Karl Jaspers was the first to define delusions based on the criteria of certainty, incorrigibility, and impossibility or falsity of the belief. Phillip Johnson-Laird defined delusions as failure to distinguish conceptual relevance, meaning irrelevant information is accepted as relevant. The definition of “delusions” continues to evolve.

Types of Delusions

Theresa Chiechi / Verywell

Types

Four types of delusions outlined in the DSM-5 include:

  • Bizarre delusions are implausible or impossible, such as being abducted by aliens.
  • Non-bizarre delusions could actually occur in reality, such as being cheated on, poisoned, or stalked by an ex.
  • Mood-congruent delusions are consistent with a depressive or manic state, such as delusions of abandonment or persecution when depressed, and delusions of superiority or fame when manic. 
  • Mood-incongruent delusions are not affected by the particular mood state. They may include delusions of nihilism (e.g., the world is ending) and delusions of control (e.g., an external force controls your thoughts or movements).

People with delusions may also exhibit confusion, agitation, irritability, aggressiveness, depression, and self-referential thinking. 

Themes

There are several different delusional themes, including:

  • Capgras delusion: This is the belief that a loved one like a mother or sibling has been replaced by an imposter.
  • Cotard delusion: This occurs in Cotard’s syndrome, and is characterized by the belief that you are dead or your body or body parts have disintegrated or no longer exist.
  • Delusion of control: This refers to the belief that an external entity is controlling your thoughts, behaviors, and impulses. This entity may be an individual like a manager, a group, or some undefined force. 
  • Delusion of grandiosity: This is an exaggerated or inflated self-belief regarding power, fame, knowledge, skill, talent, or strength. For example, a person may believe they are an Instagram influencer despite not having a following. 
  • Delusion of guilt or sin: This refers to unwarranted and extreme feelings of remorse or a severe sinking feeling that you’ve done something horribly wrong.
  • Delusion of thought insertion or thought broadcasting: This refers to the belief that thoughts have been inserted into your mind or are being broadcasted to others.
  • Delusion of persecution: This refers to the belief that you or someone close to you is being unfairly mistreated, harmed, or watched. The conviction is so strong that the person may seek help from the authorities.
  • Delusion of poverty: This is the belief that you are or are about to become destitute, are destined to fall into poverty, or are impoverished.
  • Delusion of reference: This refers to the belief that something like a poster, song, or advertisement has a direct reference to or a hidden meaning for you. A person with this delusion may see a sign that has nothing to do with them, but change their whole life plan as a result.
  • Delusional jealousy: This is the belief that your sexual partner is being unfaithful.
  • Erotomanic delusion: Also known as erotic or love delusion, this is the belief that someone, usually someone famous or otherwise out of reach, is in love with you. A person with this delusional disorder subtype may obsessively contact or try to connect with that person and make excuses for why they’re not together.
  • Nihilistic delusion: This is the belief that you or parts of you do not exist, or that some object in external reality is not actually real.
  • Religious delusion: This refers to any delusion involving a god, higher power, or spiritual theme (e.g., believing that you have special powers or are the embodiment of a prophet). This may be combined with other delusions such as the delusion of control or grandeur. 
  • Somatic delusion: This refers to the belief that one or more of your bodily organs are functioning improperly, or are diseased, injured, or altered.

Causes

Delusions are common to several mental disorders and can be triggered by sleep disturbance and extreme stress, but they can also occur in physical conditions, including brain injury or tumor, drug addiction and alcoholism, and somatic illness.

Biological or Genetic Theory

Research has suggested that delusions are more likely to occur in people who have a family history of psychotic disorders such as schizophrenia. Dysregulation of dopamine and other neurotransmitters are thought to be involved in certain types of delusional symptoms. Dopamine is a neurotransmitter that modulates motor control, motivation, and reward, so dysregulation of dopaminergic activity in the brain (namely hyperactivity of dopamine receptors in some brain regions and underactivity in others) can result in symptoms of psychosis.

Dysfunctional Cognitive Processing

The dysfunctional cognitive processing theory hypothesizes that delusions potentially come from the distorted ways people think about and explain life to themselves. Research suggests that individuals with delusions may be quicker to jump to conclusions, meaning they take in less information before arriving at a conclusion and do not consider or accept alternatives.

Those who have delusions have disturbed cognitive and social processing, meaning they can’t accurately read people and are more likely to incorrectly and negatively assume how others view them.

Defensive or Motivated Delusions

This theory proposes that delusions are a result of a defense mechanism or motivation to preserve positive self-view by attributing any negative things that happen to others or circumstances.

Other factors that could contribute to delusions include:

  • Culture and religion: Spiritual, magical, and religious delusions are common in psychotic disorders, but prevalence varies with time, place, and religion.
  • Low socioeconomic status: Delusion-like experiences have been associated with people in the general population with lower socioeconomic status. This may be due to higher levels of psychological distress and stress in this population.
  • Being hearing or sight impaired: Research has found that people with hearing impairments are at higher risk of psychosis and have been found more likely to develop schizophrenia. One explanation is that hearing or visual impairments can influence environmental misinterpretations, leading them to perceive social environments as threatening.

If you or a loved one is struggling with delusions, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area. 

For more mental health resources, see our National Helpline Database.

Diagnosis 

The diagnostic process for delusions or delusional disorder begins with a physical exam to rule out physical conditions. Your doctor will also ask about your symptoms and take a medical history.

A mental health professional will first distinguish delusions from overvalued ideas. If delusions are indeed present, the clinician will try to establish the presence of a particular mental health or another disorder that the delusion might be a symptom of.

For example, the DSM-5 criteria for delusional disorder are as follows:

  • One or more delusions are present for a duration of one month or longer.
  • The diagnostic criteria for schizophrenia has never been met. Hallucinations, if present, are not prominent and are clearly thematically related to the delusional theme.
  • Apart from the impact of the delusion(s) or its ramifications, patient functioning is not markedly impaired and their behavior is not obviously bizarre or odd.
  • If manic or major depressive episodes have occurred, they are brief compared to the duration of the delusional symptoms.
  • The disturbance is not better explained by another mental disorder such as obsessive-compulsive disorder (OCD), and is not attributable to the physiological effects of a substance or medication or another systemic medical condition.

A Word From Verywell

Delusions inherently interfere with an individual’s quality of life, causing distress and possibly disability. If unfounded beliefs are troubling you and persist for more than a month, seek help from a psychiatrist.

Treatment in the form of cognitive behavioral therapy and medications such as antipsychotics can help reduce symptoms and even lead to full remission. With the proper treatment and support from your loved ones, you can still live a healthy and productive life.

Was this page helpful?
Article Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Washington D.C.: 2013.

  2. Picardi A, Fonzi L, Pallagrosi M, Gigantesco A, Biondi M. Delusional Themes Across Affective and Non-Affective Psychoses. Front Psychiatry. 2018 Apr 5;9:132. doi:10.3389/fpsyt.2018.00132

  3. Smeets F, Lataster T, Viechtbauer W, Delespaul P; G.R.O.U.P. Evidence that environmental and genetic risks for psychotic disorder may operate by impacting on connections between core symptoms of perceptual alteration and delusional ideation. Schizophr Bull. 2015 May;41(3):687-97. doi:10.1093/schbul/sbu122

  4. Ashok AH, Marques TR, Jauhar S, Nour MM, Goodwin GM, Young AH, Howes OD. The dopamine hypothesis of bipolar affective disorder: the state of the art and implications for treatment. Molecular Psychiatry. 2017 Mar 14;22(5):666-679. doi:10.1038/mp.2017.16

  5. Bortolotti L. The epistemic innocence of motivated delusions. Conscious Cogn. 2015 May;33:490-9. doi:10.1016/j.concog.2014.10.005

  6. Cook CC. Religious psychopathology: The prevalence of religious content of delusions and hallucinations in mental disorder. Int J Soc Psychiatry. 2015 Mar;61(4):404-425. doi:10.1177/0020764015573089.x

  7. Saha S, Scott JG, Varghese D, McGrath JJ. Socio-economic disadvantage and delusional-like experiences: a nationwide population-based study. Eur Psychiatry. 2013 Jan;28(1):59-63. doi:10.1016/j.eurpsy.2011.09.004

  8. Psychiatry Advisor. The impact of deafness on hallucinations and delusions. Published October 2, 2018.