Delusions are firmly held false beliefs. They are associated with numerous disorders, including schizophrenia and delusional disorder, but can also be found in patients with affective disorders and dementia. Several different types of delusions are recognized, including erotomanic delusions, grandiose delusions, jealous delusions, persecutory delusions, delusions of control, nihilistic delusions, delusions of guilt or sin, somatic delusions, and delusions of reference. Assessment of delusions involves determination of the etiology as well as the severity and tenacity of symptom presentation. Treatment is dependent on the etiology of the symptoms and can include antipsychotic, antidepressant, or mood-stabilizing medications as well as cognitive therapy.

Definition of Delusions

Delusions are fixed beliefs that are false and have no basis in reality. Delusions can be either bizarre, such as thinking that aliens are controlling your thoughts and behaviors, or nonbizarre, such as believing that one is being watched or spied on. In addition, delusions can be mood congruent, in which the delusion is consistent with the emotional state—such as depression or mania, or mood incongruent, whereby the delusion is not consistent with the emotional state. An example of a mood-congruent delusion would be believing oneself to be God during the height of a manic episode; an example of a mood-incongruent delusion would be a depressed person’s belief that his or her thoughts are being controlled by the Central Intelligence Agency. For a belief to be considered a delusion, it must be pathological in nature.

Disorders Associated With Delusions

Delusions are symptoms of several psychological disorders and are indicative of a psychotic mental illness. Along with hallucinations, delusions are the most recognizable symptoms of schizophrenia. However, the presence of delusions alone is not sufficient to warrant a diagnosis of schizophrenia. In schizophrenia, the delusions can be either bizarre or nonbizarre.

Delusions are the predominant symptom of delusional disorder, which is a mental disorder in which the person holds one or more nonbizarre delusions in the absence of any other psychopathology. In addition, the person must not have ever met any of the diagnostic criteria of schizophrenia. In many instances, a person with delusional disorder can function normally in most aspects of life, and the only indication of mental illness is the behavior that results directly from the delusional belief. For example, a person could believe that he or she is being spied on through the electrical outlets in his or her house, so that person covers all the outlets with electric tape. With the exception of this behavior, which is directly related to the delusional thought, the person is able to maintain a job and relationships. Historically, delusional disorder was referred to as paranoia.

Delusions have also been associated with dementia, severe depression, and the manic phase of bipolar disorder.

Types of Delusions

There are several different types of delusions, such as erotomanic delusions, delusions of grandiosity, jealous delusions, persecutory delusions, delusions of control, nihilistic delusions, delusions of guilt or sin, somatic delusions, and delusions of reference.

Erotomania Delusions

An erotomanic delusion is a delusion in which the individual believes that he or she has a special, loving relationship with another person, who is usually a famous individual or someone of high standing. The subjects of delusions are often popular media figures such as politicians, actors, and singers. In certain instances, the delusional individuals believe that the subject of their delusion is communicating secret love messages to them through signals such as gestures and body posture. As part of the delusion, the delusional individuals believe that their feelings are reciprocated by the subject of their delusion. In the case of celebrities, these gesture are usually transmitted to the delusional individual through the radio or television. In most cases, the subject of the delusion has no contact with, or awareness of, the delusional individual. Erotomanic delusions are most often found in individuals diagnosed with schizophrenia or delusional disorder.

Erotomanic delusions can lead to stalking or other potentially dangerous behaviors. In some extreme cases, the delusional individual has broken into the house of the subject of the delusion and even killed the person. A number of widely reported crimes have been associated with erotomanic delusions: in 1989, Rebecca Schaeffer, a young actress, was shot and killed at her home by an individual who had an ero-tomanic delusion about her. Also, it was reported that the assassination attempt on the former U.S. president Ronald Reagan was driven by an erotomanic delusion: John Hinckley Jr. shot Reagan in the deluded belief that this action would cause the actress Jodie Foster to publicly declare her love for him.

There is some controversy about the prognosis for those who are diagnosed with erotomanic delusions. According to some researchers, such individuals respond poorly to treatment, while other researchers view the delusions as symptomatic of an underlying psychotic disorder that generally will respond to antipsychotic medications and supportive psychotherapy. There is some evidence that individuals with delusional disorder have poor compliance with treatment, as they are often so enthralled with the subject of their delusion that they cannot be persuaded to take medications that may diminish the symptoms.

Grandiose Delusions

Individuals who have delusions of grandiosity often have an exaggerated sense of self-importance or inflated worth. They may be convinced that they possess superior knowledge or skills or that they have a special relationship to a deity or a celebrity. In certain cases, the delusional individuals may actually believe that they themselves are a deity (such as Jesus Christ) or a famous person. More commonly, those with delusions of grandiosity may believe that they have achieved a great accomplishment for which they have not received sufficient appreciation and respect.

Some theorists believe that delusions of grandiosity result as a consequence of low self-esteem and negative emotions. This is known as the delusion-as-defense hypothesis. Other researchers argue that the delusions of grandiosity are an exaggerated manifestation of the individual’s true emotions and belief. This is known as the emotion-consistent hypothesis. One study investigated both hypotheses in a sample of 20 patients with grandiose delusions and found that there were no differences between covert and overt self-esteem in the sample. The authors of the study concluded that the grandiose delusions may be exaggerations of the emotional state of individuals. Grandiose delusions can be associated with schizophrenia or delusional disorder and are a common symptom of the manic phase of bipolar disorder.

Jealous Delusions

Jealous delusions, or delusions of infidelity, involve the false belief that the delusional individual’s spouse or sexual partner is unfaithful or having an affair. Delusional jealousy can involve stalking or spying on the spouse/lover as the delusional individual seeks evidence to confirm the existence of the affair. This type of delusion often stems from pathological jealousy and can seriously affect romantic relationships, and in certain cases the delusional individual’s jealousy can escalate into violence and even murder.

Persecutory Delusions

Individuals with persecutory delusions believe that specific individuals, or people in general, are “out to get them.” Individuals with delusions of persecution suspect that others are participating in intricate plots to persecute them. In some cases, they may believe that they are being spied on, drugged, or poisoned. In more extreme cases, the individuals may believe that they are the subject of a conspiracy and someone (often a government agency) wants them dead. Some delusions of persecution are vaguer and more general, such as the false belief that one’s coworkers are giving one a hard time. In other cases, the delusions can be a network of numerous well-formed false beliefs that are highly intricate and involved, such as an elaborate governmental conspiracy that can explain every aspect of the individual’s life.

Persecutory delusions are a hallmark symptom of several disorders, including paranoid schizophrenia; delusion disorder, paranoid type; and paranoid personality disorder. Paranoid delusions have also been noted in cases of severe depression and dementia.

Other Delusions

Other types of delusions include delusions of control, nihilistic delusions, delusions of guilt or sin, somatic delusions, and delusions of reference. Those with delusions of control have the false belief that someone else is controlling their thoughts, emotions, and behaviors. This can include the belief that outside forces are inserting or removing thoughts from their mind, that their thoughts are being broadcast out loud, or that someone is controlling their bodily movements. Nihilistic delusions refer to false beliefs that the world is coming to an end. Delusions of sin or guilt refer to intense feelings of guilt or sin for something the person has not done; for example, individuals with such delusions may falsely believe that they have committed a horrible crime for which they should be punished or that they are somehow responsible for natural disasters, even though this is impossible. Somatic delusions usually involve the false belief that the individual has a medical disorder or a physical deformity. These beliefs differ from hypochondriasis, as somatic delusions are often very specific and in some cases quite strange. Finally, individuals who experience delusions of reference believe that they may be receiving special messages from the television, newspaper, radio, or the way things are arranged around them. Individuals with this disorder may believe that people are talking about them or taking special notice of them even when that is not the case.

Delusions of control, nihilistic delusions, and delusions of reference are considered bizarre delusions. However, persecutory delusions, somatic delusions, grandiose delusions, as well as most delusions of jealousy and guilt are generally considered nonbizarre.

Assessment of Delusions

If a delusional disorder is suspected, an individual should be evaluated by a physician to rule out any organic etiology (such as dementia). This may include a thorough medical history, a review of the medications the patient is taking, blood workup, and possibly brain scans. If the delusions do not appear to be related to an organic cause, then the patient should undergo an evaluation by a psychiatrist or a psychologist. This evaluation will generally involve an interview and psychological assessment. There are several instruments that are used by psychologists to assess delusions. These include the MacArthur-Maudsley Delusions Assessment Schedule, the Brown Assessment of Beliefs Scale, the Positive and Negative Syndrome Scale, and the Scale for the Assessment of Positive Symptoms.

Treatment of Delusions

Delusions that are symptoms of schizophrenia will generally respond to treatment with antipsychotic medications such as thioridazine, clozapine, haloperidol, or risperidone. Delusions that are not associated with schizophrenia may not respond to antipsychotic medications, and in those cases, medications other than, or in addition to, antipsychotic medications should be used. Delusions that are symptoms of a mood disorder should be treated with antipsychotic medications as well as antidepressants or mood stabilizers. If the etiology of the delusions is medical, then resolution of the medical disorder should alleviate the delusional symptoms. Additionally, cognitive therapy has been recommended as an adjunctive therapy for individuals who experience delusions.


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