Describe and evaluate one or more biological explanations of 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.

Likewise we can not say for sure that a Schizoprenogenic mother isn’t the result of having a schizophrenic child and not the cause of schizophrenia in the child. Both the psychological and biological explanation of schizophrenia are criticised for being too simplistic an explanation of the causes of schizophrenia. However, both theories are not rigid in their views and most scientists believe that is a complex interaction between biological and environmental factors which determine the development of schizophrenia. Although most supporters of the genetic explanation believe that there is a genetic predisposition to schizophrenia and therefore accept other psychological and environmental factors.

Schizophrenia is a brain disorder revolves the way a person would think, act and the way they would see the world. They usually have a different view of the truth and this is frequently loss of contact with what going on. People that have the disorder could hear or see things that don’t exist and even speak strange, believe that others are trying to harm them, or sense they’re being watched. The biological explanation for schizophrenia, through biological faults, for instance viral infections and brain abnormalities Genetic Factors Certain psychologists predict schizophrenia can be passed down generations however this implies some people inherit the disorder from their parents. Identical twins have a higher risk of schizophrenia, meaning one of the twins can have the disorder and is a greater chance is they’re identical rather than non-identical. During my research I found that ‘Gottesman’ (1991) reviewed 40 studies and established ‘monozygotic twins have a concordance rate of 48%’, whereas dizygotic twins have a concordance rate of 17%. This demonstrates the correlation between genetics and the risk of developing schizophrenia. However if there was no genetic element there would be no difference of risk from first relatives. Yet there is 1% possibility of someone at random picked. Adopted studies is way more real way of splitting out the effects of environmental and genetic factors- adopted children later progress schizophrenia and care

The major support and refutation of the dopamine hypothesis has come from the examination of dopamine receptors in these regions of the brain. There are two main types of dopamine receptors, D1 and D2. However, within the category of D2 receptors, there are three subtypes, D2, D3, and D4. (5) Through PET scan analysis of dopamine usage in the brain and post-mordum molecular analysis of brain tissue, researcher were able to determine relative levels of dopamine receptors in patients with schizophrenia compared to non-schizophrenics. Overall analysis of dopamine

Even though the biological model is remarkable in its straightforwardness, it still has several limitations; for instance, not every individual who has a genetic indicator at a specific point in time is expected to display consequent psychopathology or a similar form of psychopathology (Miller & Mason, 2002). For example the case that every child of schizophrenic parents does not develop schizophrenia, or that not every monozygotic twin exhibits similarity in relation to schizophrenia indicates that other factors have to be taken into account. It is vital to emphasise that the failure to come across a significant prevalence of schizophrenic children of schizophrenic parents suggest that factors such as immunity, coping approaches, and invulnerability to stress, are protective factors

Another major problem with the dopamine theory is that it only takes into consideration a single neurotransmitter and neglect the roles of other neurotransmitters in schizophrenia. The findings are inconsistent where some findings proposed that the abnormality causes the availability of dopamine transporters changed, and effect to the increased or decreased of dopamine level (Fusar-Poli, and Meyer-Lindenberg, 2012), while some other findings suggested that there are other neurotransmitter such as glutamine which involved in excitatory response in the brain has played a role in resulting cognitive deficits of schizophrenia (Stone, Howes, Egerton, Kambeitz, Allen, Lythgoe, et al, 2010). These assumptions have allowed researchers to implicate schizophrenia by using another pathway or biochemical mechanism other than dopamine hypothesis or dopaminergic

Research by Johnstone in 1994, explained the biological approach of interventions, explanation and treating of schizophrenia patients (Hansell & Damour, 2005). In studies of Fisher in 2001, discoveries that the brain had more dopamine receptors know as B_2 receptors in a person suffering from schizophrenia, than a non-suffer (Hansell & Damour, 2005). Biological findings of schizophrenia suggest that a genetic factor was hereditary, but not conclusive because the element of environment does make a difference (Hansell & Damour, 2005).

However, the evidence is inconclusive since other studies have failed to reveal an excess of dopamine receptors. Further problems with the dopamine hypothesis include the finding that antipsychotic drugs which block dopamine receptors, do not appear to help a significant number of people with Sz. They appear much more effective in cases of Type 1 Sz than in Type 2. Second, these drugs block dopamine receptors quickly, yet even when they are effective, the symptoms can take weeks or even months to subside. Furthermore, the developments of new types of drugs such as clozapine which are known as antipsychotic drugs block fewer dopamine receptors than traditional anti-psychotics. However, they block many receptors for the neurotransmitter serotonin. They appear particularly effective in reducing the symptoms of Type 2 schizophrenics. Recent research suggests that Sz may result from the interaction of serotonin and dopamine rather than dopamine alone. As Davison and Neale (1998) suggest, ‘Sz is a disorder with widespread symptoms covering perception, cognition, motor activity and social behaviour. It is

Schizophrenia is a complex and highly debilitating mental illness that we are currently unable to treat in any way that guarantees success or return to previous function. It affects around 1% of the population and is associated with a thirteen-fold increase in the likelihood of suicide, so its effective control is paramount (Gogos et al., 2015). There have been several hypotheses as to the cause of schizophrenia. Many link genetic and environmental factors, and dysregulations of neurotransmitters dopamine, glutamate, and serotonin (Egbujo, Sinclair, & Hahn, 2016). The dopamine hypothesis currently suggests that hyperactive dopamine transmission in the basal ganglia leads to psychosis and underactive dopamine transmission in the prefrontal

The first theory being, the Genetic Theory. This theory proposes that schizophrenia is inherited and passed through genes. An initial study shows, one in eight children of a schizophrenic parental background develop this disorder, similarly another study concludes 75% of children will be mentally healthy. Research also states, the illness occurs in 10% of persons with a first degree relation to a family member with schizophrenia. Statistics are even high for an identical twin of a person with schizophrenia, with a probability of 40-65% of developing the disorder.

Schizophrenia is a serious mental disorder that affects millions of people and it should not be underestimated or ignored.

One of biological explanations for schizophrenia is Gotessman (1991) theory. He proved that the probability that a patient's sibling becomes ill with schizophrenia is 9%. If both parents have a schizophrenic then there is a 46 % probability that their children will be also ill. Tienari (2000) analysed 361 Finnish children where 164 biological mothers has schizophrenia. It turned out that there is a high probability of schizophrenia in children adopted, but it is about 20% increased when adoptive families have experienced relationship disorders (child has been stressed). (Cardwell, 2012)

This article provides information as to how the brain historically has used dopamine as an inhibitory neurotransmitter in regards to schizophrenia. The research discussed in this article focuses on a new discovery that indicates that glutamate, GABA, acetylcholine and serotonin alterations are also involved with schizophrenia’s pathology. With use of schizophrenic animal models, both dopamine receptors and the antipsychotic effects of the treatments that target them, and how they interact with other various neurochemical types of schizophrenia. The final topic the author discusses is how the human brain and mental abilities has evolved, causing many schizophrenic patients to be affected.

There are many causes to Schizophrenia. Many causes are genetics, brain chemistry and structure, and the environment of a human being. Genetically Schizophrenia can run through a family and can be passed on generations at a time. “Individuals with a first degree relative (parent or sibling) who has schizophrenia have a 10 percent chance of developing the disorder, as opposed to the 1 percent chance of the general population.” (Helpguide.org) Identical twins are a good example of this. “If an identical twin is diagnosed with Schizophrenia the other twin is 50 percent more likely to also be diagnosed with the mental disorder (psychcentral.com).” Brain chemistry and structure is another big factor in the cause of Schizophrenia. Neurotransmitters-

There are many theories for schizophrenia that need to be considered. However, all these ideas are strongly questioned.