Schizophrenia is a psychotic disorder characterized by major disturbances in thoughts, emotions, and behaviour: disordered thinking in which ideas are not ...
Chapter 11: Schizophrenia •
Schizophrenia is a psychotic disorder characterized by major disturbances in thoughts, emotions, and behaviour: disordered thinking in which ideas are not logically related, faulty perception and attention, flat or inappropriate affect, and bizarre disturbances in motor activity. Hospitalization rates are typically much higher among young men relative to young women. About 10% of people with schizophrenia commit suicide. Despite recent advances in treatment, many people with schizophrenia remain chronically disabled. The disability can be attributed to symptoms inherent to schizophrenia, as well as the comorbid disorders from which approximately 50% of those with schizophrenia suffer.
Schizophrenia and Comorbidity •
Comorbid personality disorders (e.g. avoidant, paranoid, dependent, and antisocial) are common and have implications for the course and clinical management of schizophrenia, that treatment should include evaluation of co-occurring substance use disorders (especially alcohol and cannabis abuse or dependence) and that attention to associated mood (especially Major Depression Disorder) and anxiety syndromes (particularly social phobia) may be important for “optimal” outcomes. Comorbid substance abuse is a major problem for people with schizophrenia. Comorbidity with OCD is also related to a previous history of suicidal ideation and suicide attempts.
Clinical Symptoms of Schizophrenia • •
The symptoms of people with schizophrenia involve disturbances in several major areas: thought, perception, and attention; motor behaviour; affect or emotion; and life functioning. No essential symptom must be present for a diagnosis of schizophrenia. Thus, people with schizophrenia can differ from each other more than do people with other disorders.
Positive Symptoms •
Positive symptoms comprise excess or distortions, such as disorganized speech, hallucinations, and delusions. They are what define, for the most part, an acute episode of
schizophrenia. Positive symptoms are the presence of too much of a behaviour that is not apparent in most people. While the negative symptoms are the absence of a behaviour that should be evident in most people. Disorganized Speech • Also known as formal thought disorder, disorganized speech refers to problems in organizing ideas and in speaking so that a listener can understand. • Speech may also be disordered by what are called loose associations, or derailment. In these cases, the person may be more successful in communicating with a listener but has difficulty sticking to one topic. • Disturbances in speech were at one time regarded as the principal clinical symptoms of schizophrenia, and they remain one of the criteria for the diagnosis. Delusions • •
Delusions, beliefs held contrary to reality, are common positive symptoms of schizophrenia. The following descriptions of these delusions are draw from Mellor (1970) - The person may be the unwilling recipient of bodily sensations of thoughts imposed by an external agency. - People may believe that their thoughts are broadcast or transmitted, so that others know what they are thinking. - People may think their thoughts are being stolen from them, suddenly and unexpectedly, by an external force. - Some people believe that their feelings are controlled by an external force. - Some people believe that their behaviour is controlled by an external force. - Some people believe that impulses to behave in certain ways are imposed on them by some external force.
Hallucinations and Other Disorders of Perception • • • •
The most dramatic distortion of perception are hallucinations, sensory experiences in the absence of any stimulation from the environment. Some people with schizophrenia report hearing their own thoughts spoken by another voice. Some people claim that they hear voices arguing. Some people hear voices commenting on their behaviour.
Negative Symptoms • •
The negative symptoms of schizophrenia consist of behavioural deficits, such as avolition, alogia, anhedonia, flat affect, and asociality. There is also some evidence that negative symptoms are associated with earlier onset of brain damage (e.g. enlarged ventricles) and progressive loss of cognitive skills.
Apathy or avolition refers to a lack of energy and a seeming absence of interest in or an inability to persist in what are usually routine activities.
A negative thought disorder, alogia can takes several forms. In poverty of speech, the sheer amount of speech is greatly reduced. In poverty of content of speech, the amount of discourse is adequate, but it conveys little information and tends to be vague and repetitive.
An inability to experience pleasure is called anhedonia. It is manifested as a lack of interest in recreational activities, failure to develop close relationships with other people, and lack of interest in sex. Clients are aware of this symptoms are report that normally pleasurable activities are not enjoyable for them.
Flat Affect •
In people with flat affect, virtually no stimulus can elicit an emotional response. The client may stare vacantly, the muscles of the face flaccid, the eyes lifeless. When spoken to, the client answers in a flat and toneless voice.
Some people with schizophrenia have severely impaired social relationships, a characteristic referred to as asociality. They have few friends, poor social skills, and little interest in being with other people.
Catatonia • • •
Catatonia is defined by several motor abnormalities. At the other end of the spectrum is catatonic immobility: clients adopt unusual postures and maintain them for very long periods of time. Catatonic people may also have waxy flexibility, whereby another person can move the person’s limbs into strange positions that they maintain for extended periods.
Inappropriate Affect •
Some people with schizophrenia have inappropriate affect. The emotional response of these individuals are out of context; for example, the client may laugh on hearing that his or her mother just died or become enraged when asked a simple question about how a new garment fits.
History of The Concept of Schizophrenia Early Descriptions •
The concept of schizophrenia was formulated by two European psychiatrists, Emil Kraepelin and Eugen Bleuler. Kraepelin first presented his notion of dementia praecox the early term for schizophrenia in 1898. Dementia praecox included several diagnostic concepts – dementia paranoids, catatonia, and hebephrenia – that had been regarded as distinct entities by clinicians in previous decades. The “dementia” in dementia praecox is not the same as the dementias we discuss in the chapter on aging, defined principally by severe memory impairments.
The Historical Prevalence of Schizophrenia •
The concept of schizophrenia was further broadened by three additional diagnostic practices: 1. U.S clinicians tended to diagnose schizophrenia whenever delusions or hallucinations were present. Because these symptoms, particularly delusions, occur also in mood disorders, many people with a DSM-II diagnosis of schizophrenia may actually have had a mood disorder. 2. People whom we would now diagnose as having a personality disorder were diagnosed as having schizophrenia according to
DSM-II criteria. 3. People with an acute onset of schizophrenic symptoms and a rapid recovery were diagnosed as having schizophrenia. The DSM-IV-TR Diagnosis •
DSM-IV-TR requires at least six months of disturbance for the diagnosis. The six-month period must include at least one month of the active phase, which is defined by the presence of at least two of the following: delusions, hallucinations, disorganize speech, grossly disorganized catatonic behaviour, and negative symptoms. A person with delusional disorder is troubled by persistent persecutory delusions or by delusional jealousy, which is the unfounded conviction that a spouse or lover is unfaithful. There are also delusions of being followed, somatic delusions (believing that some internal organ is malfunctioning) and delusions of erotomania (believing that one is loved by some other person, usually a complete stranger with a higher social status.
DSM-Proposal For Psychotic Risk Syndrome and Symptom Dimensions • Psychosis risk syndrome: Syndrome proposed by DSM-5 work group to identify young people at risk of developing schizophrenia or other psychoses. Disorganized Schizophrenia •
Kraepelin’s hebephrenic form of schizophrenia is called disorganized schizophrenia in DSM-IV-TR. Speech is disorganized and difficult for a listener to follow.
Catatonic Schizophrenia •
The most obvious symptoms of catatonic schizophrenia are the catatonic symptoms described earlier. Clients typically alternate between catatonic immobility and wild excitement, but one of these symptoms may predominate. These clients resist instructions and suggestions and often echo (repeat back) the speech of others.
Paranoid Schizophrenia •
The diagnosis paranoid schizophrenia is assigned to a substantial number of recently admitted clients to psychiatric hospitals. The key to this diagnosis is the presence of prominent delusions.
Delusions of persecution are most common, but clients may experience grandiose delusion, in which they have an exaggerated sense of their own importance, power, knowledge, or identity. Some clients are plagued by delusional jealousy, the unsubstantiated belied that their partner is unfaithful. Clients with paranoid schizophrenia often develop ideas of reference; they incorporate unimportant events within a delusional framework and read personal significance into the trivial activities of others.
Evaluation of the Subtypes •
Undifferentiated schizophrenia applies to people who meet the diagnostic criteria of schizophrenia but not the criteria for any of the three subtypes. The diagnosis of residual schizophrenia is used when the client no longer meets the full criteria for schizophrenia but still shows some signs of the disorder.
Etiology of Schizophrenia Family Studies •
The negative symptoms of schizophrenia appear to have a stronger genetic component.
Adoption Studies •
Children reread without contact with their so-called pathogenic mothers were still more likely o become schizophrenic than were the control participants.
Molecular Genetics •
It does not appear that the genetic predisposition to schizophrenia is transmitted by a single gene; several multior polygenic models remain viable. • The hunt for schizophrenia-related gens has proven more difficult than expected for several reasons, including: 1. Lack of preciseness in defining the boundaries of the clinical phenotype. 2. Absence of biological tests that confirm diagnostic categorization. 3. Clinical heterogeneity and the complex nature of schizophrenia.
Endophenotypes are characteristics that reflect the actions of genes predisposing an individual to a disorder, even in the absence of diagnosable pathology.
Biochemical Factors Dopamine Activity • • • • •
The theory that schizophrenia is related to excess activity of dopamine is based principally on the knowledge that drugs effective in treating schizophrenia reduce dopamine activity. The dopamine receptors that are blocked by first-generation or conventional antipsychotics are called D2 receptors. Further indirect support for the dopamine theory comes from the literature on amphetamine psychosis. Amphetamines can produce a state that closely resembles paranoid schizophrenia. Excess dopamine receptors may not be responsible for all the symptoms of schizophrenia; in fact, they appear to be related mainly to positive symptoms. Amphetamines worsen positive symptoms and lessen negative ones. Antipsychotics lessen positive symptoms, but their effect on negative symptoms is less clear; some studies show ne benefit. The excess dopamine activity that is thought to be most relevant to schizophrenia is localized in the mesolimbic pathway, and the therapeutic effects of antipsychotics on positive symptoms occur by blocking dopamine receptors there, thereby lowering activity in this neural system. The mesocortical dopamine pathway begins in the same brain region as the mesolimbic, but it projects to the prefrontal cortex. Prefrontal cortex is thought to be especially relevant to the negative symptoms of schizophrenia.
Other Neurotransmitters •
Low levels of glutamate have been found in cerebrospinal fluid of people with schizophrenia.
Schizophrenia and the brain: Structure and Function Enlarged Ventricles •
Post-mortem analyses of the brains of people with schizophrenia consistently reveal abnormalities in some areas of the brain,
although the specific problems reported vary across studies and many of the findings are contradictory. The most consistent finding is of enlarged ventricles, which implies a loss of subcortical brain cells. Research also shows a reduction in cortical grey matter in both the temporal and frontal regions and reduced volume in basal ganglia and limbic structures. Enlarged ventricles are not specific to schizophrenia, as they are also evident in the CT scans of people with other psychoses, such as bipolar disorder.
The Prefrontal Cortex • •
The prefrontal cortex is known to play a role in behaviours such as speech, decision-making, and willed action, all of which are disrupted in schizophrenia. Lack of illness awareness is related to poorer neuropsychological performance more often in clients with schizophrenia than in bipolar participants, supporting the hypothesis that lack of awareness is related to defective frontal-lobe functioning. MRI studies have shown reductions in grey matter in the prefrontal cortex. In a type of functional imaging in which glucose metabolism is studied in various brain regions while clients perform psychological tests, clients with schizophrenia have shown low metabolic rates in the prefrontal cortex. Clients with schizophrenia showed less prefrontal activation (prominent dysfunction) in specific areas relative to comparison participants, suggesting that “cognitive control deficits strongly contribute to episodic memory impairment in schizophrenia. The frontal hypoactivation is less pronounced in the nonschizophrenic twin of discordant MZ pairs, again suggesting that this brain dysfunction may not have a genetic origin. Violent people with schizophrenia and a history of anti-social and/or substance use manifest neural dysfunction affecting basal or orbital parts of the prefrontal cortex.
Congenital and Developmental Considerations •
It was reported that the presence at birth or in infancy of “craniofacial/midline anomalies and/ or early functional impairments that commonly occur as symptoms of CNS [central nervous system] anomaly” were associated with a doubling of the risk for schizophrenia spectrum disorder.
Contemporary Research •
White matter forms the physical connections of the functional networks. The authors concluded that white matter pathology plays a critical role in the cognitive impairments seen in schizophrenia.
Social Class and Schizophrenia • • •
Rate of schizophrenia was found to be twice as high in the lowest social class as in the second-lowest class. Some people believe that stressors associated with being in a low social class may cause or contribute to the development of schizophrenia – the sociogenic hypothesis. Another explanation of the correlation between schizophrenia and low social class is the social-selection theory, which reverses the direction of causality between social class and schizophrenia.
The Family and Schizophrenia •
Early theorists regarded family relationships, especially those between a mother and her son, as crucial in the development of schizophrenia. At one time, the view was so prevalent that the term schizophrenogenic mother was coined to describe the supposedly cold and dominant, conflict-inducing parent who was said to produce schizophrenia in her offspring.
Relapse and the Role of the Family: •
Expressed emotion (EE): In the literature on schizophrenia, the amount of hostility and criticism directed from other people to the client, usually within a family. • Recently discharged schizophrenia clients and their high- or lowEE families were observed as they engaged in a discussion of a family problem. Two key findings emerged: 1. The expression of unusual thoughts by the clients (“If that kid bites you, you’ll get rabies”) elicited higher levels of critical comments by family members who had previously been characterized as high in EE. 2. In high-EE families, critical comments by family members led to increased expression of unusual thoughts. • Some researchers have related the effects of stress on the hypothalamic-pituitary-adrenal (HPA) axis to the dopamine theory. Stress is known to activate the HPA axis, causing cortisol to be secreted. In turn, cortisol is known to increase dopamine
activity and may thereby increase the symptoms of schizophrenia. Developmental/High-Risk Studies of Schizophrenia • •
Children who later developed schizophrenia had lower IQs than did members of various control groups. Teachers described schizophrenic boys as disagreeable in childhood and preschizophrenic girls as passive. Both men and women were described as delinquent and withdrawn in childhood. Preschizophrenic children showed poorer motor skills and the more expressions of negative affect. Negative-symptom schizophrenia was preceded by a history of pregnancy and birth complications and by a failure to show electrodermal responses to simple stimuli. Positive-symptom schizophrenia was preceded by a history of family instability, such as separation from parent and placement in foster homes or institutions. The American Psychiatric Association (2004) treatment guidelines for schizophrenia recommend a multi-point treatment course that consists of several strategies known to improve functional outcome: 1. Selection and application of antipsychotic medication to control acute psychotic symptoms, including strategies for maintaining adherence 2. Identification and treatment of comorbid disorders, including substance use and depressive disorders. 3. Use of psychosocial treatment approaches with demonstrated effectiveness in improving symptoms and ability to function socially and vocationally.
Biological Treatments Shock and Psychosurgery •
In 1935, Egas Moniz a Portuguese psychiatrist, introduced the prefrontal lobotomy, a surgical procedure that destroys the tracts connecting the frontal lobes to lower centres of the brain. His initial reports claimed high rates of success. A related procedure known as a leucotomy is a more circumscribed and specific procedure than a lobotomy.
Antipsychotic drugs are also referred to as neuroleptics because they produce side effects similar to the symptoms of neurological disease.
First-Generation (Conventional) Antipsychotic Drugs •
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One of the more frequently prescribed antipsychotic drugs in the past 50 years, phenothiazine, was first produced by a German chemist in the late nineteenth century. Not until the discovery in the 1940s of the antihistamines, which have a phenothiazine nucleus, did phenothiazines receive much attention. A French chemist, Charpentier, prepared a new phenothiazine derivative, which he called chlorpromazine. This drug proved very effective in calming people with schizophrenia. As already mentioned, phenothiazines derive their therapeutic properties from their ability to block dopamine receptors in the brain, thus reducing the influence of dopamine on thought, emotion, and behaviour. There classes of drugs reduce the positive symptoms of schizophrenia but have much less effect on the negative symptoms. Clients who respond positively to antipsychotics are kept on socalled maintenance doses of the drug, just enough to continue the therapeutic effect. Commonly reported side effects of antipsychotics include dizziness, blurred vision, restlessness, and sexual dysfunction. In addition, a group of particularly disturbing side effects, termed extrapyramidal side effects, stem from dysfunctions of the nerve tracts that descend from the brain to spinal motor neurons. Extrapyramidal side effects resemble the symptoms of Parkinson’s disease. Other side effects include dystonia, a state of muscular rigidity, and dyskinesia, an abnormal motion of voluntary and involuntary muscles, producing chewing movements, as well as other movements of the lips, fingers, and legs. Akasthisia is an inability to remain still; people pace constantly and fidget. In a muscular disturbance of clients with schizophrenia, called tardive dyskinesia, the mouth muscles involuntarily make sucking, lip-smacking, and chin-wagging motions. Finally, a side effect called neuroleptic malignant syndrome occurs in about 1% of cases. In this condition, which can sometimes be fatal, severe muscular rigidity develops, a accompanied by fever. The heart races, blood pressure increases, and the client may lapse into a coma.
Second-Generation (Atypical) Antipsychotics •
In the decades following the introduction of antipsychotic drugs, there appeared to be little interest in developing new drugs to treat schizophrenia. This situation change markedly following the introduction of clozapine (Clozaril), which appeared to produce therapeutic gains in people with schizophrenia who do not respond well to traditional antipsychotics.
Personal Therapy: A broad form of cognitive behaviour therapy designed to address the numerous factor and processes associated with relapse into schizophrenia.
An approach called cognitive enhancement therapy (CET) developed by Hogarty and his colleagues was evaluated in a twoyear RCT of clients who were also taking medication. The approach was compared with an enriched supportive therapy that included educational and supportive aspects of personal therapy. The CET-specific focus is on computer-based training in attention, memory, and problem solving, as well as social cognitive skills. The scaffolding model requires instructors to select tasks that reflect the clients’ current capabilities so that eventually they are able to solve problems for themselves.
Community-based teams of doctors, nurses, and social workers called PACT (program for Assertive Community Treatment) have been set up to ease the pressure caused by the closing of provincial psychiatric hospitals and to reduce the number of people with schizophrenia and other serious psychiatric disorders who end up in hospital emergency wards.
Halfway house and group homes are protected living units, typically located in large, formerly private residences. Here, clients discharged from a psychiatric facility live, take their meals, and gradually return to ordinary community life by holding a part-time job going to school. As part of what is called vocalization rehabilitation, these former hospital clients learn marketable skills that can help them secure employment and thereby increase their chances of remaining in the community.