Discuss the genetic and biochemical explanations of schizophrenia
Discuss the genetic and biochemical explanations of schizophrenia (25 marks) Biological explanations have been used in attempting to explain many mental disorders. However, such explanations have proved more successful in accounting for the development of schizophrenia than most other disorders. Two main branches of this type of explanation are genetic factors, which explain schizophrenia through inheritance of abnormal genes; and biochemical factors, which explain schizophrenia through the presence of abnormal neurochemicals. Nonetheless, there is contrasting evidence for both and it has been suggested that you can't completely separate these explanations from each other as schizophrenia is a complex and multi-cause disorder. In order to use twin studies to support genetic explanations of schizophrenia, when one twin is known to be schizophrenic, researchers are interested in the probability that the other twin may also be. This is known as concordance. Gottesman (1991) summarised 40 twin studies and found that the concordance rate was 48% when a monozygotic or identical twin had schizophrenia, but only 17% when a dizygotic twin or non-identical twin had schizophrenia. These findings strongly suggest that genetic factors are important - the reason why identical twins have a much higher concordance rate than fraternal twins is because they are much more similar genetically
Schizophrenia As A Genetic Disorder
Discuss the view that schizophrenia is a genetic disorder. (30) The fact that schizophrenia has been found to run in families has led to the inference that it has a genetic basis. According to the genetic hypothesis, the closer related the family member to the schizophrenic the greater the chance of developing schizophrenia. However, experts do agree that if anything is inherited in schizophrenia, it is a genetic predisposition to develop the disease rather than a certainty. Evidence supporting the genetic basis of acquiring schizophrenia comes from family studies. These show that the risk of developing schizophrenia is greater for those more closely related to the schizophrenic. This is supported by Gottesman who found that if both parents have schizophrenia there is a 46% chance of developing the disease, if a single parent has schizophrenia there is a 16% chance and if a sibling has schizophrenia there is an 8% chance. In addition to this there is also a 17% chance of developing schizophrenia in families where the identical twin of one parent has schizophrenia - this shows the influence of nature over nurture. However, the fact that concordance rates increase with genetic relatedness may be explained by the fact that this is because they are also likely to spend more time together, which means environmental factors may be influential, maybe more so than genetic. Also,
"The biological approach tells us all we need to know about schizophrenia" with reference to the quote discuss genetic explanations of schizophrenia.
"The biological approach tells us all we need to know about schizophrenia" with reference to the quote discuss genetic explanations of schizophrenia. The biological approach claims that schizophrenia is caused by genetic, neurotransmitter or structural brain faults. The first of these is the claim that schizophrenia is genetically passed on; if a relative is diagnosed with schizophrenia the first degree relatives will develop schizophrenia. Grottesman (1991) fount that in monozygotic twins if one was diagnosed with schizophrenia then 48% of the time the other twin would go on to develop schizophrenia. In dizygotic twins Grottesman found that if one was diagnosed with schizophrenia then 18% of the time the other will go on to develop schizophrenia. This shows strong support when compared to the general population where 1% of people are diagnosed with schizophrenia. However, monozygotic twins are often reared in a very similar environment; they were born at about the same time and they get treated similarly. This implies that concordance rates between twins aren't reliable as the children will have been treated similarly therefore environmental factors can be an explanations for the development of schizophrenia in a pair of monozygotic twins. The same can be said for first degree relatives; they will still share a similar environment which could provide an explanation for
Outline and Evaluate One Biological and One Psychological Explanation of Schizophrenia
Outline and Evaluate One Biological and One Psychological Explanation of Schizophrenia Schizophrenia is a mental disorder characterised by 'abnormal' thought processes, psychomotor problems, lack of motivation, and disturbance of affect. As a syndrome there are a variety of symptoms that fall under these categories, although they will not all be displayed in one individual. It is thought that it may be incorrect to label schizophrenia as one disorder, as it is believed to in fact be a series of separate disorders that have been placed under this overarching diagnosis. Currently there is no one explanation that can completely explain why the development of schizophrenia happens, however there are many approaches from both biological and psychological areas that attempt to explain the aetiology. One of the biological theories of schizophrenia is the Dopamine Hypothesis. This is a biochemical explanation that suggests the disorder is caused by an excess of the neurotransmitter dopamine in the brain. The main evidence for this has come from studies on both living and post-mortem brains of sufferers from schizophrenia, and also from observations made during drug therapies. This theory acts as one explanation of how the genetic theory may work, in that certain genes that are inherited could cause an increase in dopamine production or receptor density. Originally, studies of the
Discuss the biological explanation for schizophrenia taking in to account genetics and brain structure
Discuss the biological explanation for schizophrenia taking in to account genetics and brain structure Schizophrenia is a complex illness that affects people’s moods, feelings, perceptions, thoughts, behaviour and ability to communicate. Sufferers are usually withdrawn and prefer to be left alone and are not especially prone to violence. One biological explanation involves genetics to describe how schizophrenia occurs. This theory relies on twin studies, family studies and adoption studies to provide support for their opinions. Gottesman et al (1987) constructed a family study to investigate the genetic component of schizophrenia. The results showed that for closer relations, there was a higher concordance rate. This concludes that genetic factors do play a moderate role in family patterns of schizophrenia. Gottesman also reported that in twins, the concordance rate for monozygotic twins, the concordance rate was 46%, whereas the concordance rate for dizygotic twins was only 17%. Rosenthal (1963) also found a case of female schizophrenic quadruplets. This makes the evidence for a genetic basis for schizophrenia stronger. However, they only looked at three studies, which is still a very small number. We cannot base our opinions on concordance rates because they suggest that there are other factors that influence schizophrenia, therefore it can be considered quite vague.
Describe two research studies into the causes of schizophrenia. Evaluate them in terms of whether schizophrenia is a genetic or social illness.
Chyrise cox 6/03/2009 Psychology of Individual Differences: Assignment Three Describe two research studies into the causes of schizophrenia. Evaluate them in terms of whether schizophrenia is a genetic or social illness. Schizophrenia is a psychological illness that has been intensely researched for a number a years. There have been many theories that all claim to have found the cause and reasons why schizophrenia occurs. Genetic or social influences are the two main argued points in this psychological debate. In this assignment I will look at the two main theories which provide some substantial evidence for each explanation. Schizophrenia is a chronic, severe, and disabling brain disorder that has been recognized throughout recorded history. People with schizophrenia may hear voices other people don't hear or they may believe that others are reading their minds, controlling their thoughts, or plotting to harm them. These experiences are terrifying and can cause fearfulness, withdrawal, or extreme agitation. People with schizophrenia may not make sense when they talk, may sit for hours without moving or talking much, or may seem perfectly fine until they talk about what they are really thinking. Because many people with schizophrenia have difficulty holding a job or caring for themselves, the burden on their families and society is significant as well. Available
Is schizophrenia caused by genetic (nature) or environmental (nurture) factors? Critically discuss with reference to both psychological theory and research.
Transfer-Encoding: chunked Is schizophrenia caused by genetic (nature) or environmental (nurture) factors? Is schizophrenia caused by genetic (nature) or environmental (nurture) factors? Critically discuss with reference to both psychological theory and research. Student ID: Name of Tutor: Unit number: Unit name: Psychology 101 Word count:1200 Abstract The purpose of this essay is to find out if schizophrenia is caused by genetic or environmental factors. The essay discussed both genetic and environmental factors critically with reference to both psychological theory and research. The essay examined a wide range of literature and resources ranging from biological and environmental theories, scholarly articles and peer reviewed journals The essay supports the assertion that genetic factors play a more prominent role in the cause of schizophrenia than environmental factors. The paper concluded by maintaining that though genetic factors are more responsible for schizophrenia than environmental factors, it acknowledges the importance of environment factors in the cause of schizophrenia. That both factors are interwoven and significant in the cause of schizophrenia. Is schizophrenia caused by genetic (nature) or environmental (nurture) factors? Critically discuss with reference to both psychological theory and research. What is schizophrenia? The Diagnostic and
Bio explanations of schizophrenia
Biological Explanations of Schizophrenia One biological explanation for schizophrenia is that genetic factors are involved. This view considers that certain individuals possess certain genes which predispose an individual to schizophrenia. This can be explained in more detail using studies on twins. According to research identical twins are said to share 100% of their genes and therefore if one twin has schizophrenia, there's a 48% chance of the other twin developing it too. Gottesman summarised 40 twin studies and found that the concordance rate for MZ twins was 48% and the concordance rate for DZ twins was about 17%. Concordance rates were also studied by Cardano et al using the Maudsley twin register. They found concordance rates to be 40% for MZ twins and 17% for DZ twins. This provides strong evidence in which genetic factors play a key role in schizophrenia. However because concordance rates are not 100%, it is said that there must be some kind of environmental input. Loehlin and Nicholas argued that the reason for higher concordance rates in MZ rather than DZ twins was due to DZ twins being treated more similarly so therefore producing a greater environmental similarity. Nevertheless because schizophrenia has chances of becoming inherited, we would expect to find that relatives also have similar chances of developing this disorder. This is supported by Kendler et al
Biological Explanations of Schizophrenia
Discuss research in biological explanations of schizophrenia Schizophrenia is a psychiatric disorder involving loss of contact with reality and a range of symptoms. One biological explanation for schizophrenia is that genetic factors are involved. This view considers that certain individual's posses certain genes which predispose an individual to schizophrenia. Furthermore the condition can be inherited and as a result we would expect to find that relatives have similar chances of developing the disorder. One other biological explanation for schizophrenia is the Viral Hypothesis. This states that schizophrenia is a mental deterioration at an early age. In other words brain damage at the time or before the time of birth could be a factor in the development of schizophrenia. They have enlarged ventricles in their brain and post-mortems have found that their brains are lighter. There certainly evidence that supports that we can inherit a disposition for schizophrenia through genetic causes. Research to prove this comes twin studies of MZ and DZ twins. Gottesman and Shields found a higher concordance rate of MZ twins both having the disorder than DZ twins who only share 50% of their genes, although the concordance rate was not 100%. This certainly highlights the huge influence genetics have on inheriting the condition however, if genetics were the sole cause we would expect
Biological Explanations of Schizophrenia
SC1 There is strong evidence that biological factors play a large part in the development of schizophrenia. It has been known for a long time that sch runs in families. This could be because families share the same disadvantaged environments, but research evidence from family, twin and adoption studies suggests that genetic factors are also important. First-degree relatives share an average of 50 per cent of their genes with each other, while second degree relatives share only 25 percent. Research evidence has looked to see if there is a correlational link between inheriting schizophrenia and genetic similarity. Kendler et al (1985) found that first-degree relatives of schizophrenics are 18 times more likely to contract the disorder than the general population. Family studies are often inconclusive because they are conducted retrospectively, after people have been diagnosed. Therefore we can question the reliability of findings, as the relationship between genetic similarity and susceptibility to schizophrenia is not fully clear; a longitudinal study would be better However, a longitudinal study of this nature would be hard and very time consuming to conduct. Twin studies are another way of establishing a genetic link; they look at the difference in concordance between MA and DZ twins. Cardno et al (1999) found a 40 per cent concordance rate of sch in MZ twins, compared
