Delusions in schizophrenia

The negative/deficit symptoms of schizophrenia are associated with low DA activity in the prefrontal cortex. Positive symptoms, such as hahudnations and delusions in schizophrenia, are related to excessive DA activity in mesolimbic DA neurons. 

D. Antiparkinson drugp help to decrease hallucinations and delusions in patients witii schizophrenia... 

Schizophrenia is a chronic, complex psychiatric disorder affecting approximately 1% of the population worldwide. The chronic nature of the illness, in addition to the early age of onset, results in direct and indirect health care expenditures in the U.S., which amount to approximately 30 to 64 billion dollars per year [4]. It is perhaps the most devastating of psychiatric disorders, with approximately 10% of patients committing suicide. The dopamine hypothesis of schizophrenia postulates that overactivity at dopaminergic synapses in the central nervous system (CNS), particularly the mesolimbic system, causes the psychotic symptoms (hallucinations and delusions) of schizophrenia. Roth and Meltzer [5] have provided a review of the literature and have concluded a role for serotonin as well in the pathophysiology and treatment of schizophrenia. The basic premise of their work stems from the known interaction between the serotonergic and dopaminergic systems. 

Deiusionai Disorder. Patients with delnsional disorder share the presence of delusions with schizophrenia patients. However, the delnsions are not bizarre as they often are in schizophrenia. Patients with delnsional disorder often fnnction fairly well in society. They can nsnally hold employment and typically remain active members of their families. Delnsional disorder patients do not have the negative symptoms of schizophrenia, do not experience hallncinations, and do not suffer from the gross social impairment of schizophrenia. They may, however, have circumscribed social problems that are directly related to the content of their delusions. The delusions often are believable or at least somewhat plausible. 

Cognitive psychotherapeutic techniques have further been developed since their introduction by Beck et al. (1979), who demonstrated their effectiveness in the treatment of depression. Several studies have extended Beck s cognitive therapy to adulthood schizophrenia with encouraging clinical results. The efficacy of cognitive-behavioral approaches could be demonstrated in several key areas in schizophrenia, especially therapy-resistant hallucinations and delusions. Several approaches have also addressed therapeutic efforts in the treatment of associated symptoms such as anxiety and depression. In addition, cognitive-behavioral techniques have been shown to be effective in treatment of chronic schizophrenia, resulting in reduction of distress and disruption due to hallucinations and delusions. In some studies anxiety and depression associated with schizophrenia could also be reduced to some extent. The value of these techniques in children and adolescents has yet to be demonstrated. 

This category is attributed to Kahibaum and Kraepelin, who saw paranoia as a chronic, unremitting system of delusions distinguished by both the absence of hallucinations and the deterioration seen in schizophrenia. This disorder is characterized by one or more nonbizarre delusions of at least 1 month s duration. 

Schizophrenia-related disorders, such as schizophreniform disorder, can closely mimic an acute exacerbation of mania. Attention to premorbid personal and family history may help differentiate them from mood disorders. A definitive diagnosis may not be possible, however, until the course of the illness is followed for a period of time. Clinical clues include the propensity of bipolar manics (in contrast to schizophrenics) to demonstrate pressured speech, flight of ideas, grandiosity, and overinclusive thinking. Hallucinations are less common than delusions in both mania and depression, with delusions normally taking on the qualities of expansivity, hyperreligiosity, or grandiosity. Delusions are also relatively less fixed than in schizophrenia. 

Man s history has been characterized by a seemingly insoluble ambivalence toward altered states and intense experience. Freud said that in schizophrenia things become conscious that should remain unconscious. As Kierkegaard pointed out, however, "One cannot transcend one s self objectively. The existential realization of a unity of finite and infinite which transcends existence comes only in the moment of passion." Tolstoy had a similar view "It is possible to live only as long as life intoxicates us as soon as we sober again we see that it is all a delusion, and a stupid one " Despite their emphasis on intensity, both men conceded that "It is perfectly true that only terror to the point of despair develops a man to his utmost—though of course many succumb during... 

Initially, the neuroleptics were used to manage severe anxiety, agitation, and aggression in individuals with severe mental illness such as schizophrenia, a psychotic illness characterized by delusions, hallucinations, and disorganized, illogical thinking. The first neuroleptic used in schizophrenia was chlorpromazine (Thorazine) in 1952. Additional neuroleptics were later developed to treat a variety of other disorders and conditions in children and adults, including autism, attention-deficit hyperactivity disorder (ADHD), bipolar dis-... 

The role that dopamine plays in regulating mood and emotional stability can be at least partially grasped by examining dopamine s role in schizophrenia and drug addiction. Schizophrenia is a disorder characterized by delusions, hallucinations, withdrawal from external reality, and emotional unresponsiveness. The dopamine theory of schizophrenia, proposed in 1965, attributes the disorder to elevated brain concentrations of dopamine or to a hypersensitivity of dopaminergic receptors, especially the D2 and D4 receptor subtypes. Several drugs used to treat schizophrenic patients bind to D2 and D4 receptors and block the dopaminergic response. 

The primary difficulty in formulating any definition of mental aberrance in general and schizophrenia in particular is that any such definition will necessarily reflect the cultural bias out of which it is formed. Behavior considered abnormal or pathological in one culture may be quite congruent with the norms of another. Belief in witchcraft might be indicative of paranoid delusion in one culture but might represent a prevailing view in another. 

The secondary symptoms that may also be present must be considered as part of the diagnostic impression. The first and probably the most common secondary symptom is delusions. A delusion can be defined simply as a belief that a client holds despite evidence to the contrary. In schizophrenia there may be numerous beliefs so disturbing that functioning is impaired. Often these delusions are systematized and may involve family and friends. These may be diffrcult for loved ones to tolerate, because they cannot see any real or external basis for such behavior or understand why it is so difficult to control. 

PCP binds to a site within the ion channel of the NMDA receptor that blocks the influx of cations, thereby acting as a non-competitive antagonist. PCP produces a syndrome in normal individuals that closely resembles schizophrenia and exacerbates symptoms in patients with chronic schizophrenia. Ketamine is an anesthetic that has approximately a 10- to 15-fold lower affinity for the NMDA receptor, and it produces the characteristic cognitive deficits of schizophrenia. When ketamine is administered to patients with schizophrenia stabilized with antipsychotic medication, it produces delusions, hallucinations, and thought disorder, consistent with the patient s typical pattern of psychotic relapse. Consistent with this model, chronic PCP administration also increases subcortical dopamine release, particularly in the nucleus accumbens, emphasizing the reciprocal modulation of the glutamate and dopamine neuronal systems in schizophrenia. 

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