Explain the background, types, and symptoms of schizophrenia.

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Schizophrenia is a severe mental illness that interferes with a person’s ability to think and to communicate. Researchers have studied the illness for decades, and while genetic factors contribute to the illness, the specific genetic mechanisms and how they interact with environmental factors remain unknown.
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According to the National Alliance on Mental Illness (NAMI) in 2013, approximately 1.1 US adults (about 2.4 million people) lived with schizophrenia. It is considered to be one of the most severe mental illnesses, because its symptoms can have a devastating impact on the lives of patients and their families. The patient’s thought processes, communication abilities, and emotional expressions are disturbed. As a result, many patients with schizophrenia are dependent on others for assistance with daily life activities.

Schizophrenia is often confused, by the layperson, with dissociative identity disorder (commonly known as multiple personality disorder), is an illness defined as having two or more distinct personalities existing within the person. The personalities tend to be intact, and each is associated with its own style of perceiving the world and relating to others. Schizophrenia, in contrast, does not involve the existence of two or more personalities; rather, it is the presence of psychotic symptoms and characteristic deficits in social interaction that define schizophrenia.

The diagnostic criteria for schizophrenia have changed over the years; however, certain key symptoms for a diagnosis as noted by the Diagnostic and Statistical Manual of Mental Disorders: DSM-5 (2013) include delusions, hallucinations, disorganized speech (such as frequent incoherence or connecting a sequence of unrelated ideas), completely disorganized or catatonic behavior, and such negative symptoms as diminished emotional expression or avolition (general lack of motivation or drive). The DSM-5 is published by the American Psychiatric Association and is periodically revised to incorporate changes in diagnostic criteria.

Of the five symptoms listed above and in the DSM-5, at least two of the symptoms must be present in an individual for at least one month. One of two of the symptoms must include delusions, hallucinations, or disorganized speech. Further, the presence of other disorders, such as drug reactions or organic brain disorders associated with aging, must be ruled out. Thus, the diagnosis of schizophrenia typically involves a thorough physical and mental assessment. Although no single individual symptom is necessary for a person to receive a diagnosis of schizophrenia, according to the DSM-5, the persistent and debilitating presence of hallucinations, a hallucinated voice commenting on the individual, or hallucinated conversations between two voices is a strong indication of schizophrenia. The presence of delusions or hallucinations and loss of contact with reality is referred to as psychosis and is often present in schizophrenia, but psychotic symptoms can be seen in other mental disorders (for example, bipolar disorder or substance-induced psychotic disorder), so the term “psychosis” is not synonymous with the diagnosis of schizophrenia. The DSM-5 also notes that not one single symptom denotes a diagnosis of schizophrenia. In other words, two individuals may be diagnosed with the disorder and have different symptoms, which then make them look and act completely different from one another.

Although not emphasized by the DSM-5, international and cross-cultural study of the symptoms of schizophrenia has noted that the most frequently observed symptom in schizophrenia is patients’ lack of insight. That is, despite sometimes overwhelming evidence of gross abnormalities in perception and behavior, patients with schizophrenia are likely to deny that those problems are symptomatic of a disorder.

Each of these symptoms can take a variety of forms. Delusions are defined as false beliefs based on incorrect inferences about external reality. Delusions are classified based on the nature of their content. For example, grandiose delusions involve false beliefs about one’s importance, power, or knowledge. The patient might express the belief that he or she is the most intelligent person in the world but that these special intellectual powers have gone unrecognized. As another example, persecutory delusions involve beliefs of being persecuted or conspired against by others. The patient might claim, for example, that there is a government plot to poison him or her.

Hallucinations are sensory experiences that occur in the absence of a real stimulus. In the case of auditory hallucinations, the patient may hear voices calling or conversing when there is no one in physical proximity. Visual hallucinations may involve seeing people who are deceased or seeing inanimate objects move on their own accord. Olfactory (smell) and tactile (touch) hallucinations are also possible.

The term “affect” is used to refer to observable behaviors that are the expression of an emotion. Affect is predominantly displayed in facial expressions. “Flat” affect describes a severe reduction in the intensity of emotional expressions, both positive and negative. Patients with flat affect may show no observable sign of emotion, even when experiencing a very joyful or sad event.

Among the symptoms of schizophrenia, abnormalities in the expression of thoughts are a central feature. When speech is incoherent, it is difficult for the listener to comprehend because it is illogical or incomplete. As an example, in response to the question “Where do you live?” one patient replied, “Yes, live! I haven’t had much time in this or that. It is an area. In the same area. Mrs. Smith! If the time comes for a temporary space now or whatever.” The term “loose associations” is applied to speech in which ideas shift from one subject to another subject that is completely unrelated. If the loosening of associations is severe, speech may be incoherent. As an illustration of loose associations, a patient described the meaning of “A rolling stone gathers no moss” by saying, “Inside your head there’s a brain and it’s round like a stone and when it spins around it can’t make connections the way moss has little filaments.”

With regard to speech, a variety of other abnormalities are sometimes shown by patients. They may use neologisms, which are new words invented by the patient to convey a special meaning. Some show clang associations, which involve the use of rhyming words in conversation: “Live and let live, that’s my motto. You live and give and live-give.” Abnormalities in the intonation and pace of speech are also common.

In addition to these symptoms, some patients manifest bizarre behaviors, such as odd, repetitive movements or unusual postures. Odd or inappropriate styles of dressing, such as wearing winter coats in the summer, may also occur in some patients. More deteriorated patients frequently show poor hygiene. To meet the diagnostic criteria for schizophrenia, the individual must show signs of disturbance for at least six months.

Types and Treatment of Schizophrenia

Prior to the release of the DSM-5, clinicians recognized five subtypes of schizophrenia when making a diagnosis (the differentiation among these subtypes was based on the symptom profile, and the criteria for subtype designation were described in DSM-IV-TR). They were catatonic schizophrenia, disorganized schizophrenia, paranoid schizophrenia, residual schizophrenia, and undifferentiated schizophrenia. Because no one symptom is sufficient for a diagnosis of schizophrenia, patients vary in the numbers and the intensity of their symptoms. It was for this reason as well as the low reliability and poor validity in diagnosing and treating schizophrenics when using the subtypes that the subtypes were eliminated in the DSM-5.

In his writings shortly after the turn of the twentieth century, Eugen Bleuler often used the phrase “the group of schizophrenias,” because he believed the disorder could be caused by a variety of factors. In other words, he believed that schizophrenia may not be a single disease entity. Today, some researchers and clinicians who work in the field take the same position. They believe that the differences among patients in symptom patterns and the course of the illness are attributable to differences in etiology.

Because schizophrenic symptoms have such a devastating impact on the individual’s ability to function, family members often respond to the onset of symptoms by seeking immediate treatment. Clinicians, in turn, often respond by recommending hospitalization so that tests can be conducted and an appropriate treatment can be determined. Consequently, almost all patients who are diagnosed with schizophrenia are hospitalized at least once in their lives. The majority experience several hospitalizations.

Research on the long-term outcome of schizophrenia indicates that the illness is highly variable in its course. A minority of patients have only one episode of illness, then go into remission and experience no further symptoms. Unfortunately, however, the majority of patients have recurring episodes that require periodic rehospitalizations. The most severely ill never experience remission but instead show a chronic course of symptomatology. For these reasons, schizophrenia is viewed as having the poorest prognosis of all the major mental illnesses.

Prior to the 1950s, patients with schizophrenia were hospitalized for extended periods of time and frequently became institutionalized. There were only a few available somatic treatments, and those proved to be of little efficacy. Included among them were insulin coma therapy (the administration of large doses of insulin to induce coma), electroconvulsive therapy (the application of electrical current to the temples to induce a seizure), and prefrontal lobotomy (a surgical procedure in which the tracts connecting the frontal lobes to other areas of the brain are severed).

Also, in the 1950s, a class of drugs referred to as antipsychotic medications were discovered to be effective in treating schizophrenia. Antipsychotic drugs significantly reduce some of the symptoms of schizophrenia in many patients. The introduction of antipsychotic medications (also called neuroleptics) in combination with changes in public policy led to a dramatic decline in the number of patients in public mental hospitals. Antipsychotic medications have freed many patients from confinement in hospitals and have enhanced their chances for functioning in the community. Not all patients benefit from typical antipsychotic medications, and the discovery of new classes of medications has offered hope to patients and families. Despite the benefits of antipsychotic medications, they can also produce serious side effects, particularly tardive dyskinesia, a movement disorder associated in some patients with chronic use of typical antipsychotic medications.

The public policy that has contributed to the decline in the number of hospitalized patients with schizophrenia is the nationwide policy of deinstitutionalization. This policy, which has been adopted and promoted by most state governments in the years since 1970, emphasizes short-term hospitalizations, and it has involved the release of some patients who had been in institutions for many years. Unfortunately, the support services that were needed to facilitate the transition from hospital to community living were never put in place. Consequently, the number of homeless schizophrenic patients has increased dramatically. Some of these are patients whose family members have died or have simply lost touch with them. Other patients have withdrawn from contact with their families, despite efforts by concerned relatives to provide assistance. The plight of the homeless mentally ill is of great concern to mental health professionals.

History and Future Directions

Writing in the late 1800s, the eminent physician Emil Kraepelin was among the first to document the symptoms and course of this illness, referring to it as dementia praecox (dementia of early life). Subsequently, Bleuler applied the term “schizophrenia,” meaning splitting of the mind, to the disorder. Both Kraepelin and Bleuler assumed that organic factors were involved in developing schizophrenia. Contemporary research has confirmed this assumption; brain scans reveal that a significant proportion of schizophrenia patients do have organic abnormalities. The precise nature and cause of these abnormalities remain unknown.

In the majority of cases, the onset of schizophrenic symptoms occurs in late adolescence or early adulthood. The major risk period is between twenty and twenty-five years of age, but the period of risk extends well into adult life. The majority of individuals to not develop schizophrenia after the age of forty-five. For some patients, there are no readily apparent abnormalities prior to the development of illness. For others, however, the onset of schizophrenia is preceded by impairments in social, academic, or occupational functioning. Some are described by their families as having had adjustment problems in childhood. Childhood schizophrenia, which is defined as onset of schizophrenic symptoms prior to age thirteen, is relatively rare. It is estimated to occur in about one out of every ten thousand children. When schizophrenia is diagnosed in childhood, the same diagnostic criteria and treatments are applied.

Schizophrenia shows no clear pattern in terms of its distribution in the population. It occurs in both males and females, although it tends to have a slightly earlier onset in males than in females. The illness strikes individuals of all social, economic, and ethnic backgrounds. Some patients manifest high levels of intelligence and are excellent students prior to becoming ill; others show poor academic performance and signs of learning disability. Although the specific pathophysiology associated with schizophrenia remains obscure, the preponderance of evidence demonstrates a significant role for genetic factors in the risk for developing schizophrenia. According to the National Institute of Mental Health, schizophrenia occurs in roughly 1 percent of the general population, but it occurs in roughly 10 percent of individuals with a first-degree relative (parent, sibling) with the disorder. The risk increases when one has an identical twin with schizophrenia; that individual then has a 40–60 percent chance of developing the disorder.

Schizophrenia is an illness that has been recognized by medicine for more than a hundred years. During this time, only modest progress has been made in research on its etiology. Some significant advances have been achieved in treatment, however, and the prognosis for schizophrenia is better now than ever before. Moreover, there is reason to believe that the availability of new technologies for studying the central nervous system will speed the pace of further discovery.


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