Predisposing Factors to Schizophrenia

What is Schizophrenia?

Schizophrenia is a long term mental illness. The disease is characterised by positive and negative symptoms. The positive symptoms are those such as hallucinations (seeing or hearing things that don't exist) and delusions (strange fixed beliefs that are not true), while negative symptoms include lack of emotion, limited speech and an inability to enjoy any activities.

Schizophrenia is one of the most costly and inadequately treated mental illness. It’s prevalence across the life span and a lack comprehensive and effective treatment expand its maximal morbidity. The emotional and physical losses clients and families experience are tragic. Personal costs arise from a long term consequences of schizophrenia associated with social, vocational and emotional impairment, which increase the risk of life time dependency on families and society and incidence of substance abuse (Andreasen, 1991; Mueser et al., 1992).
Historically, schizophrenia has been described as a chronic, debilitating, incurable mental illness, but now this is changing. This neurobehavioral disorder challenge nurses to appreciate the link between neurobiological factors and behavior seen in schizophrenia and other psychotic disorder. Linking this factors enables nurses to use the nursing process to asses, plan, intervene and evaluate client responses to treatment modalities. Even in this day of immense neurobiological expansion and technological advances, it cause remains unknown. Inspite of its enigma, there is increasing evidence suggesting that schizophrenia is a complex system disorder with mediating biological and behavioral processes that are influenced by stress. Schizophrenia along with other chronic mental illness, must be treated effectively and efforts to prevent. Its onset must be aggressively pursued (Ciompi; 1989; Straus, 1989)

Predisposing factors
Biological. Behavior related to maladaptive neurobiological responses have been described in writing and art since biblical times. Causes proposed for these strange behavior ranged from demon possession, bad blood and witchcraft, to the full moon. Fortunately, modern science is now identifyng many clues to the actual causes of these disorder.
The brain abnormalities causing maladaptive neurobiological responses are only beginning to be understood. The majority of what is known today has been discovered by research stemming from advances in brain imaging. Brain imaging studies indicate that virtually all areas of the brain are involved in person with schizophrenia. However psychotic behaviors are most likely to be related to lesions in the frontal, temporal, and limbic regions. Studies have suggested that the prefrontal cortex and the limbic cortex never fully develop in the brain of patients with schizophrenia. Positron emission tomography studies have confirmed that blood flow to the prefrontal and limbic cortical regions is consistently dysfunctional in patients with schizophrenia. These findings presented a fundamental problem is understanding the Dopamine (DA) connection in schizophrenia, as it had been believed that dopamine neurons did not exist in the prefrontal cortex. With the recent discovery of the D4 receptor, researchers have identified the role of the prefrontal and limbic cortices in the regulation of stress-related dopamine activity.
Neurons in the prefrontal cortex are particularly important for memory. A decrease in the numbers of these specific neurons may be the cause of loose associations memory-guided responses and sensory responses should be the same but are altered in schizophrenia. The resulting deficit is seen in the absence of working memory or the bringing of stored information to conscious awareness.
Other biological models suggest the importance of prenatal, perinatal, neonatal, and childhood neurological factors, several researchers have proposed that schizophrenia is acquired in late fetal development or the perinatal period. These findings suggest that symptoms of schizophrenia may be caused by changes in the structure of brain tissue and failure of certain neuronal cells to migrate ti their ultimate location.
Finally, family studies involving twins and adopted children historically have served as the basic of research design attempting to identify a genetic cause for schizophrenia. In these studies, identical twins who separated at birth with at least one adopted were found to have higher rates of schizophrenia in both twins than occurred in nonidentical pairs of siblings.
Current research, however, focuses on families with a high incidence of schizophrenia and is moving toward locating specific susceptibility genes trough genemaping techniques. Rigorous family studies have clearly shown that schizophrenia aggregates in families, although little is known about the mode or what it is that is transmitted through genes. Current genetic research is focusing on several areas: (1) how many genes are there? (2) how common are they? And (3) what are their individual effects?

Psychological. In the past, in the absence of identified biological causes for schizophrenia, psychological, sociological, and environmental influences became the focus. For most of the twentieth century schizophrenia has been viewed as an illness that was caused partly by the family and partly by some individual character flaw. The mother was believed to be anxious, overprotective, or cold and unfeeling, the father was distant overbearing. Marital conflict and families that stayed together for the sake of children were blamed. There were theories describing a ‘schizophrenic’ mother and theories described how communicating in double messages could ‘double bind’ a person into developing schizophrenia.
Schizophrenia was also viewed by some as failure to accomplish an early stage of psychosocial development. For example, an infant’s inability to form a trusting relationship could lead to a lifetime of intrapsychic conflict. Schizophrenia was seen as the most severe example of inability to cope with stress. Disturbances inability, inability to attach to a love object, and inability control basic drivers also served as key theories. It is critically important for psychiatric nurses to reality however, that with the psychobiological discoveries recent years, most of these psychodynamic theories was found little scientific support. In addition, they can be a very negative impact on patient-family alliances and nurses and other mental health care professionals
THE ‘schizophrenogenic’ mother was described as one who gave her child conflicting and confusing messages about their relationship, realizing in schizophrenia. How would this theory affect the mothers of people with schizophrenia, their relationship with their ill children, and their relationship with care providers?
Sociocultural. Some theories proposed that proverty, society, and cultural disharmony could cause schizophrenia or that individuals chose to become schizophrenic to cope with the insanity of the modern world. Factors proposed that schizophrenia was caused by living in the city or living on the isolation in the country. Although accumulated stress related to environmental factors is likely to contribute to the onset of schizophrenia and to relapses, neurobiological findings point to causes for the primary development of psychotic disorders.

Precipitating Stressors.
Biological. Interference in a brain feedback loop that relates the amount of information that can be provided at a given time has been identified as one posted biological stressor. Normal information processing in a predetermined series of neural activities. Visual and auditory stimuli are initially screened and fillid by the thalamus and sent for processing by the frontal lobe. If too much informations is sent at once or more information is faulty, the frontal lobe send a reload message to basal ganglia. The basal ganglion turn send a message to the thalamus to slow transmissions to the frontal lobe. The decreased ganglion already present in the frontal lobe impairs the faulty of this feedback loop to perform. There is faulty to regulate the basal ganglia, and ultimately the message to slow down transmissions to the frontal lobe sends occurs. The result is information-processing over and the neurobiological responses described in the training of this chapter.
Another possibility biological stressor is the abnormal coping mechanism that may occur in the schizophrenia.
Gating is an electrical process involving electrolytes. It refers to inhibitory and excitatory nerve action potentials and the feedback occurring within the nervous system related to completed nerve transmissions. Decreased gating is demonstrated by a persons’s inability to selectively attend to stimuli. For example, as a baseball game the individual with schizophrenia would be unable to differentiate the noise from the crowd, the organ, the team, or the public address system. Normally, when individuals hear a loud noise they become startled, however, when the noise is repeated, there is decreased startled response. For example, if you hear a neighbor setting off firecrackers on the fourth of july you become startled, when you hear a seccond explosion, you are generally less startled. The person with schizophrenia is just as startled the second time and maybe even more than the first. This inability to ‘gate’ a noise stimulus causes individuals to become frightened in crowds or wherever there is increased noise.
Environmental stress. There is no scientific researchindicating that stress causes schizophrenia, however, studies of relapse and symptom exarcerbation provide evidence that stressand problems with coping may predict the return of symptoms. The stress-diathesis medel described by Liberman and colleagues states that schizophrenic symptoms develop based on the relationship between the amount of stress that a person experiences and an internal stress tolerance threshold. This is an important model because it integrates biological, psychological, and sociocultural factors in explaining the development of schizophrenia.
Symptom triggers. Finally, precursor and stimuli often precede a new episode of the illness. The word trigger is used to described these stressor. Common triggers of neurobiological responses related to health. Environment and attitude and behavior.


References
Deborah, Antai-Otong.1995. Biological and behavioral concept.Gail Kongable
Harold I, Kaplan, Sadock, Benjamin J. 1995. Comphrehensive text book of psychiatry VIPhiladelphia:Saunders
Yosep, Iyus. 2007. Keperawatan Jiwa. Bandung : Refika Aditama
Stuart & Sundeen. 1995. Principles & Practice Of Psychiatric Nursing Fifth Edition. St. Louis Missouri : Mosby