Genetic Explanation of Depression Research on the heredity of depression within families shows that some individuals are more likely than others to develop the disorder. If you have a parent or sibling with depression, you may be 1.5 to 3 times more likely to develop the condition than those who do not. This suggests there may be some kind of genetic influence. Gershon 1990 studied 10 families, and found rates of MDD in first degree relative ranged between 7-20%, which i considerably higher than the rest of the population. Weisman 1984 also found that relatives of people diagnosed with depression before the age of 20 had 8x greater chance of being diagnosed with it.
A family study conducted by Gottesman reported that the rate of schizophrenia in the general population is 1% whereas the rate in people where both parents suffer in 46%. He also found that if one parent suffered the rate was 13%. Gottesman concluded that the closer the bloodline the higher the risk. He and Shields then conducted a study on the concordance rates of schizophrenia in 40 sets of twins. They found that in dizygotic twins the rate
Outline and evaluate one biological explanation of schizophrenia (24 marks) There are three main biological explanation of schizophrenia: genetic, neuroanatomical and biochemical explanation. According to gentic explanation genes can cause schizophrenia the condance rate can represent the probabilty of someone in the family developing schizophrenia. Twins studies are essential for investigating the caused of schizophrenia because the identical twinse share the same identical structure whereas, non-identical twins only share 50%. Gottesman examined about 40 studies and found about 48% concordance rate in identical twince and only 17% in non-identical twins, indicating genes can cause schizophrena. On the other hand Tienari investigated 155 adopted children whose biological mothers were schizophrenic.
“Studies show that a child born to two schizophrenic parents has about a 46% chance of developing a schizophrenic disorder than a child not born into this type of family.” (Weiten, 2001, p. 595). These studies show an inherited tendency for schizophrenia. Nevertheless, as identical twins do not show 100% concordance rates, twin studies also indicate environment as a key factor in developing
Although it isn't clear in the paragraph whether Harry has a twin or not, if he did this could have a massive influence on his behaviour. Let's say Harry had an mono-zygotic twin, who shared a 100% concordance rate with him. Early twin studies generally found higher concordance for criminality amongst MZ than DZ twins, which would support the suggestion of a genetic influence. However, this research has said to be flawed due to a combination of small samples and poor methods of determining whether a particular twin pair was MZ or DZ. The rationale underlying the use of twins in explaining criminal behaviour is that if 1 MZ twin shows signs of aggressive behaviour, and the other one does too, then it is down to genetic influence.
Describe two or more biological explanations of OCD (9 marks) The biological approach works on the assumption that abnormality is caused by dysfunctional biological processes and that it is these factors mean that an illness is more likely to occur in certain people. One explanation for OCD focuses on the role of genetics which argues that people are born with a pre disposition to have OCD. Evidence on genetics and OCD has involved using twin studies and first degree relatives. It has been found that those who have a first degree relative with OCD, such as parent of sibling, are 5 times more likely to have OCD themselves. This suggests that certain genetic factors may lead to abnormal functioning of areas of the brain causing illnesses such as OCD.
Bateson et al (1956) suggested that children who frequently receive contradictory messages from their parents are more likely to develop schizophrenia e.g. a mother hugs her child but then disapprovingly tells him off for being “clingy”. This is known as the double-bind theory. There is evidence to support the double-bind theory. Berger found that schizophrenics reported a higher recall of double-bind statements by their mothers than non-schizophrenics.
Nowadays psychosurgery is used only in very exceptional circumstances. Many studies using MRI scans have evaluated the appropriateness of psychosurgery and have actually shown that there is abnormal functioning in the frontal lobes of the brain in schizophrenia sufferers, and therefore it may be that some kind of psychosurgery that reduces the functioning of the frontal lobe may actually help to control the symptoms of some sufferers. Tooth and Newton (1961) reported on the effectiveness of psychosurgery carried out between 1942 and 1954. Few sufferers (4%) had died of the surgery, and at least 69% showed improvement of some kind, 41% significantly so. They stated that it is therefore very effective.
This data might be inconsistent because “girls tend to exhibit aggression more covertly. Girls may use verbal, rather than physical, aggression, often excluding others or spreading rumors about another child” (Hamilton & Armando, 2008, 861). Another risk factor is coexisting conditions. ADHD is the most common condition that can coexist with oppositional defiant disorder . In a study called Multimodal Treatment Study of Children with ADHD, “researchers found that 40 percent of children with ADHD also meet diagnostic criteria for oppositional defiant disorder “ (Hamilton & Armando, 2008, 863).
The veil that someone is high on drugs is that equivalent to the majority of schizophrenics (National Mental Health Institute, 2007). Though drug addiction is not always the case in patients a larger factor, however, is the need for many schizophrenics to intake nicotine. Most people suffering from schizophrenia will consume some sort of nicotine at three times that of a normal citizen, which raises the question if it is brain dependence to the chemical (National Mental Health Institute, 2007). Researchers today are looking to see if it is a biological need or if many patients realize that the drug will combat many of the medications and treatments given by the therapists. Depression is often misinterpreted in residual schizophrenic, one who no longer suffers from hallucinations, but has no will to live (Mental Health America, 2011).