Biological Psychology of Schizophrenia: Causes and Treatments

Introduction

Schizophrenia is a mental disorder characterized by delusions, hallucinations, and distorted thinking. The exact cause of schizophrenia is unknown, but it is believed to be a combination of genetic and environmental factors. Schizophrenia has been described throughout history, with the first known case dating back to the mid-6th century BC. In ancient times, it was considered to be caused by a range of factors — from environmental to spiritual (Kyziridis, 2005). However, it was not until the early 19th century that schizophrenia began to be recognized as a distinct mental disorder. In 1809, a French physician named Philippe Pinel first described schizophrenia as a "mental derangement," but Emil Kraepelin is generally regarded as the first to conceptualize it as a discrete condition. The term itself was coined in 1911 by Eugen Bleuler, who introduced the word schizophrenia based on the Greek root words meaning "split mind" (Kyziridis, 2005).

Today, the DSM-5 conceptualizes schizophrenia as a mental disorder characterized by abnormal thinking, emotions, and behaviors. People with schizophrenia may experience hallucinations and delusions (Swingler, 2013). They may also have disorganized speech and think in ways that are difficult to understand. Schizophrenia can be a very disabling condition, making it difficult for people to function in work, school, or social situations. However, with treatment, many people with schizophrenia are able to lead productive lives. Over the centuries, there have been many different theories about what causes schizophrenia. This paper describes the development of the disorder, provides biological and psychological perspectives on theories and causes, discusses treatments, and describes the experience of living with a schizophrenic family member and its challenges.

Development of the Disorder

The exact cause of schizophrenia is unknown, but it is believed to be a combination of genetic and environmental factors. Owen et al. (2016) refer to it as "a complex, heterogeneous behavioral and cognitive syndrome that seems to originate from disruption of brain development caused by genetic or environmental factors, or both" (p. 86). Research suggests that schizophrenia may be caused by changes in brain structure and function. Symptoms of schizophrenia typically begin in early adulthood, with men often developing the disorder at a younger age than women (Patel et al., 2014).

According to Andreasen (2000), there is a phenotype that mutates to produce schizophrenia: "the phenotype should be defined on the basis of abnormalities in neural circuits and a fundamental cognitive process" (p. 106). Others posit that schizophrenia is inheritable, while still others suggest it develops in response to one's environment (Van Os et al., 2010). What is most likely is that schizophrenia results from a confluence of factors, beginning at a crucial stage of development — depicted by Erikson as the crisis point between identity and role confusion during the adolescent stage of psychosocial development (Shriner & Shriner, 2014). It is during this pivotal stage that the individual can experience acute psychosocial stress capable of overwhelming the proper ordering of chemical pathways in the brain, leading to the progressive debilitation of daily functioning until the individual displays symptoms consistent with a schizophrenia diagnosis.

Biological and Psychological Perspectives on Causes

Heritability and environmental factors represent the respective biological and psychological perspectives on why schizophrenia occurs. The biological perspective is underpinned by the theory that the disorder is caused by a chemical imbalance in the brain. According to this view, schizophrenia results from a defect in the brain's ability to produce or process certain neurotransmitters. This theory is supported by evidence that schizophrenic symptoms can be relieved by antipsychotic medication, which works by correcting the chemical imbalance (Andreasen, 2000).

The heritability perspective emphasizes the role of genetics in the etiology of the disorder, while the environmental perspective emphasizes the role of therapy and early intervention. Although there is no definitive answer as to which perspective is correct, both have merit. For example, studies comparing identical and fraternal twins suggest that genetics does play a role in the development of schizophrenia (Chapter 4, 2016; Patel et al., 2014). However, environmental factors such as exposure to stress or trauma may also be contributors. It is worth noting that heritability and environmental factors are not mutually exclusive; it is likely that both play a role in the development of this complex disorder (Kyziridis, 2005).

Environmental factors that could be responsible for the onset of schizophrenia include stress, trauma, or abuse. Stressful life events have been found to be associated with an increased risk of developing schizophrenia, particularly when those events occur during adolescence or early adulthood. Traumatic experiences, such as physical or sexual abuse, can also contribute to the development of schizophrenia. Exposure to toxins or infection during pregnancy has also been linked to an increased risk of the disorder. While the exact cause remains unknown, these environmental factors may play a significant role in its development (Van Os et al., 2010).

Epigenetic changes in the brain can result from severe trauma, upsetting the balance and function of neural pathways and making it difficult for a person to adjust to internal and external stimuli in the way a non-traumatized individual might. Epigenetic changes can be broadly defined as modifications to the genome that do not involve changes in the underlying DNA sequence. These changes can affect the way genes are expressed, and they have been implicated in a wide range of biological processes, including brain development and function. Epigenetic mechanisms are thought to play a role in mediating the effects of environmental factors on the brain, and they have been linked to a number of psychiatric disorders. While much remains to be learned about epigenetics, it is clear that these changes can have profound impacts on brain development and function (Owen et al., 2016).

Conclusion

Schizophrenia is a serious mental illness that affects about 1% of the population. The exact cause of schizophrenia is unknown, but it is thought to be a combination of genetic and environmental factors. Symptoms include delusions, hallucinations, disordered thinking, and problems with emotion and behavior. Schizophrenia can be very disabling, making it difficult for those affected to function in day-to-day life. Treatment typically includes medication and psychotherapy, and family members can play an important role in supporting their loved ones. Anyone who suspects that someone they know has schizophrenia should encourage that person to seek professional help.

References

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