Different Causes of Schizophrenia (genetic influences (Twin Studies (The…
Different Causes of Schizophrenia
The case of the Genain quadruplets also reveals an important consideration and studying genetic influences on behavior-unshared environments. The impression is that good parents expose their children to favorable environments and bad parents give them unstable experiences.
Even identical siblings can have different parental and family experiences and can therefore be exposed to varying degrees of biological and environmental stress.
If they are raised together, identical twins share 100% of their genes and 100% of their environment, whereas fraternal twins share only about 50% of their genes and 100% of their environment.
The Offspring of Twins
If your parent is an identical twin with schizophrenia, you have about a 17% chance of having the disorder yourself, a figure that holds if you are the child of an unaffected identical twin whose co-twin has the disorder.
If your parents is the twin schizophrenia, you have about 17% chance of having schizophrenia yourself.
If your parent does not have schizophrenia but your parents fraternal twin does, your risk is only about 2%
A 1938 study showed that the severity of the parents disorder influenced the likelihood of the child’s having schizophrenia: the more severe the parent schizophrenia, the more likely the children were to develop it.
All forms of schizophrenia we’re seen within the families. It does not appear that you’ll inherit a predisposition for what was previously diagnosed as paranoid schizophrenia
You may inherit a general predisposition for schizophrenia that manifests in the same form or differently form that of your parents
Linkage and Association Studies
Three of the most reliable genetic influences that make one susceptible to schizophrenia you quit sections on chromosome 8, chromosome 6, and chromosome 22
Genes are responsible for making some individuals vulnerable to schizophrenia
From a sample of almost 20,000 women with schizophrenia, the researchers found 190 children who had been given up for adoption. The data from the study support the idea that schizophrenia represents a spectrum of related disorders, all of which overlap genetically.
If an adopted child had a biological mother with schizophrenia, that child had about a 5% chance of having the disorder.
If the biological mother had schizophrenia or one of the related psychotic disorders, the risk of the adopted child would have one of these disorders rose about 22%.
Currently, a number of endophenotypes are being explored by large group of scientists which is studying more than 1,200 individuals with schizophrenia and their families.
There are shared neuroanatomical similarities that provide evidence of schizophrenia is presents across individuals from different cultures that provide evidence of schizophrenia is presents across individuals from different cultures
The lack of an adequate mental health infrastructure in and middle income countries is also a problem for providing appropriate and consistent care to those suffering from schizophrenia
Schizophrenia is universal, affecting all racial and cultural groups studied so far affecting all racial and cultural groups studied so far.
The different rates of schizophrenia, therefore, maybe partially the result of misdiagnosis rather than the result of any real cultural distinctions.
We now know that people in widely diverging cultures have the symptoms of schizophrenia, which supports the notion that it is a reality for many people worldwide.
In additional factor contributing to this imbalance maybe the levels of stress associated with factors such as stigma, isolation, and discrimination.
Prenatal and Perinatal Influences
Fetal exposure to viral infection, pregnancy complications, and delivery complications are among the environmental influences that seem to affect whether or not someone develops schizophrenia.
Several studies have shown that schizophrenia maybe associated with prenatal exposure to influenza, viruses, or infections.
There is evidence that the prenatal and perinatal environment are correlated with the development of schizophrenia.
The evidence of pregnancy complications and the delivery complications and their relationship to later schizophrenia suggest, on the surface, that this type of environmental stress combined with genetic and other variables may trigger the expression of the disorder.
Adults who have schizophrenia show deficits and their ability to perform certain tasks and to attend during reaction time exercises
Brain damage or dysfunction may cause or accompany schizophrenia, although no one site is probably responsible for the whole range of systems
Many children with a parent who has the disorder, and who are therefore at risk, tend to show subtle but observable neurological problems, such as I have normal reflexes and inattentiveness.
Several brain sites are implicated in the cognitive dysfunction observed among people with schizophrenia, especially the prefrontal cortex, various related cortical regions, and sub cortical circuits, including the thalamus and the striatum.
Also the neuroleptics Block the reception of dopamine quite quickly, the relevant symptoms subside only after several days or weeks, more slowly than we would expect
These drugs are only partly helpful in reducing the negative symptoms of schizophrenia
A significant number of people with schizophrenia are not help other use of dopamine antagonists.
psychological and social influences
There are strong individual differences in how people experience the same life events, and people with schizophrenia may experience events differently than those without the disorder.
Stressors in life may influence development of psychosis, possibly by increasing stressors later in life, making individuals more sensitive to later stressors, or both.
Healthy people who engage in a combat during 04 often display temporary symptoms that resemble those of schizophrenia.
Researchers have studied the effects of a variety of stressors on schizophrenia. Living in a large city, for example, it is associated with an increased risk of developing schizophrenia-suggesting the stress of urban living may precipitate its onset.
Families and Relapse