Biological Dysfunction as a Cause for Schizophrenia Essay

For major depression between monozygotic and dizygotic twins suggest a heritability of about 37%. It is lower than the heritability of bipolar disorder or schizophrenias.

Schizophrenia is a disorder that is characterized by a broken thought process and poor emotional responses. Typical symptoms of this disorder include delusions, paranoia, hallucinations, social dysfunctions,

“As with many mental disorders, the causes of schizophrenia are poorly understood. Friends and family commonly are shocked, afraid or angry when they learn of the diagnosis. People often imagine a person with schizophrenia as being more violent or out-of-control than a person who has another kind of serious mental illness. But these kinds of prejudices and misperceptions can be readily corrected (Physical Central, 2013)”. These are just some of the common misconceptions about this tragic disease. One of the best ways to describe this disease is as a “split mind” where literally the person feels as if they are in an unrealistic world that is real to them like a hallucination. “Family, twin, and adoption studies support the role of genetic influences in schizophrenia. Immediate biological relatives of people with schizophrenia have about 10 times greater risk than that of the general population. Given prevalence estimates, this translates into a 5 to 10 percent lifetime risk for first-degree relatives (including children and

The biological explanation of schizophrenia also claims that the disorder can be inherited. The more common the disorder is among the biological relatives and the closer the degree of genetic relatedness increases the risk of the child developing schizophrenia. Gottesman’s research (1991) found a genetic link with schizophrenia when looking at children and their relatives. The research discovered that children with two schizophrenic parents have a concordance rate of 46% compared to children who just have one schizophrenic parent to children who have a concordance rate of 13% and siblings just 9%. The genetic theory of schizophrenia also suggests that monozygotic twins (twins who a genetically identical) should have a higher concordance rate of schizophrenia than dizygotic twins (twins who are not genetically identical) because they have a closer degree of genetic relatedness.

Those that are recognized increase the possibility only by extremely small quantities. Consequently, these “genome scans” are improbable to offer a whole image of a person’s danger for acquiring a mental disorder like schizophrenia. Additionally, it possibly endures more than genes to instigate the disorder (Stefansson, Ophoff, Steinberg, Andreassen, Cichon, Rujescu, & Kahn, 2009). Experts reflect communications amongst genes and the environment are essential for schizophrenia to grow. Several environmental issues might be comprised, such as revelation to viruses or malnourishment before birth, difficulties during birth, and other not yet recognized psychosocial issues.

Identical twins can be compared to see whether when one twin has a disorder, the other one has it too. This provides us with a concordance rate the extent to which two individuals are similar to each other in terms of a particular trait. There are low concordance rates for some mental disorders e.g. phobias but relatively high concordance rates for others e.g. schizophrenia.

In support of this Kendler et al found that first degree relatives of those with schizophrenia are at 18 times more risk than the general population. Research has also found that schizophrenia symptoms may have a genetic component. This was suggested by Malaspina, who found that patients who have schizophrenia in their family histories are more likely to develop negative symptoms than those families who are schizophrenia free. In evaluation of family studies it may be concluded that they are not very reliable as they are retrospective. The studies for family studies where taken place when diagnosis was under a more liberal use of the term schizophrenia. Twin studies have also shown a genetic pre-disposition. Gottesman found 48% risk of schizophrenia in MZ twins compared to only 17% in DZ twins. Similar to the Gottesman study two other studies showed higher concordance rates for MZ twins and lower in DZ twins however each had slightly different results. McGuffin et al argues this is because of the use of different diagnostic criteria, which may affect the validity of the results. On the other hand the researchers used blind techniques to obtain the results eliminating any researcher bias.

However, evidence seems to disprove this theory. In some instances, both identical twins are schizophrenics and other times only one is affected. To defend this theory, it should be noted that this research is complicated. Identical twins are relatively rare, especially twins who are both diagnosed with schizophrenia. Studies have also shown that children with one parent diagnosed with schizophrenia have a ten percent chance of suffering from schizophrenia. When both parents are schizophrenic, their risk raises to approximately forty percent. Little is known about the Environmental Theory. The theory is built mainly on the effects of stress on human behavior. Most researchers agree that stress alone cannot be the main cause of schizophrenia. Most researchers agree that stress could possibly trigger or worsen the symptoms when the illness is already present. Other researchers focus on drug abuse. Like stress, certain drugs such as amphetamines can make psychotic symptoms worse if a person already has schizophrenia. Furthermore, these drugs can, in a sense, create schizophrenia. Other researchers that support the Environmental Theory believe that "slow viruses" may be to blame. Slow viruses are viral infections that go undetected for long periods of time. Signs and symptoms are delayed and may occur many years after the first infection. The Bio-Chemical Theory suggests that schizophrenia is caused

Schizophrenia is a chronic brain disorder that changes the way certain people interpret reality. (Schizophrenia) Around the world, in the general population a normal person only has about a 1% chance of developing this disease in their lifetime. It can however be passed along genetically. Say a second degree relative i.e. aunt/uncle, grandmother/grandfather or cousin is schizophrenic, you have a 5% chance of becoming schizophrenic sometime in your life. If your mother or father is a schizophrenic, your chances go up to 12%. If your brother or sister have the illness your chances rise to 8% but if you are the fraternal twin to a schizophrenic, your chances of becoming one are about 14%. If both parents are schizophrenic you now have a 39% chance but if you are the identical twin of a schizophrenic your chances of

Biological theorists believe that individuals may have a genetic predisposition for the schizophrenia if a close family member has been diagnosed with the disorder. Stress during adolescent years seems to provoke the disorder among individuals who have a family history of the disorder. In addition, this theory suggests biochemical abnormalities related to the dopamine neurotransmitters may also contribute to the illness as the brains neurotransmission of the dopamine is too frequent in occurrence (Comer, 2005). CAT and MRI scans have also indicated that abnormal brain structuring may also play a role in the development of schizophrenia due to a common occurrence of enlarged ventricles within schizophrenia sufferers (Comer, 2005). Various parts of the brain may not develop for function properly which seems lead to Type II schizophrenia. Studies have also pointed towards the idea that exposure to certain viruses before birth may lead to the eventual development of schizophrenia (Comer, 2005).

An important topic we discussed in class is schizophrenia. The typical age of onset in schizophrenia is during the individual’s mid-20s, but symptoms can start appearing during their late teens until their early 30s (Vernon, 2015). Additionally, only 1% of the population are diagnosed with schizophrenia, regardless of their gender or demographic background, which is a unique aspect compared to other diagnoses. Numerous studies, conducted under a variety of biological etiologies, serve as evidence for schizophrenia. Theses studies include: family studies, twin studies, adoption studies, linkage studies, pregnancy studies, and viral infections studies (Vernon, 2015), but the most dominant is that of identical twins as they have a high concordance rate of 48% (Cromer 479). This means that identical twins (monozygotic twins) have a higher risk of developing schizophrenia compared to fraternal twins (dizygotic twins). Additionally, neurochemistry studies examined that people with schizophrenia have more dopamine receptors, especially D-2 receptors, causing them to have “problems [with] attention, perception, and thought” (Cromer 481). This is known as the dopamine hypothesis which is important because researchers initially thought that it was too much dopamine that led to schizophrenia, but numerous studies verified that this idea was false and rather, that it was an overactive dopamine system that produced more dopaminergic activity. Specifically, through drug testing,

Schizophrenia can be passed down thru generations even though there is not a specific gene associated with the disorder. It is considered to be a combination of genes that make a person susceptible to becoming schizophrenic. This information is found mainly thought the study of twins. By having the same genes it can be viewed why genes contribute to the potential of schizophrenia. Even though genetics is a viable factor in the analysis of the cause of schizophrenia there are more supporting factors found in neurotransmitters.

1978 shields discussed 11 studies of the identical and non-identical co-twins of over 1300 schizophrenics from seven countries and then of these comparisons showed a higher concordance rate among identical twins. (A, C, Smith 1982 p.g 93) Research is still going on today to find out more about how genes and life events influence who gets schizophrenia.

Aim: The aim of this experiment was to explore the synergistic effects of heritability and environment in the cases of two brothers with schizophrenia.

Within twins, monozygotic twins have a 48% probability if their twin is diagnosed with schizophrenia, and with dizygotic twins it is a 17% probability (Kalat, 2015). This shows that there is a genetic bases for schizophrenia, it also highlights that other non-genetic factors must play a role in the development of the disorder. These results have been backed by many research carried out on adoption studies. An adoption study in Finland carried out aimed to test the hypostasis that family rearing plays a factor in the development of schizophrenia (Tienari et al, 2004).Their research found that adoptees at high genetic risk (biological mother had schizophrenia) were more sensitive to problems in the adoptive family environment. Adoptees with high risk and a severally dysfunctional family rearing were significantly coordinated with a diagnosis of a schizophrenia spectrum disorder (Tienari et al, 2004). In support of the diathesis model neither high risk nor dysfunctional rearing were significantly linked with a diagnosis (Tienari et al, 2004). The research found that a ‘healthy’ adoptive family, acted as a ‘protective effect’ for the adoptees with