Biological Explanations of Schizophrenia Flashcards

Flashcards about Biological Explanations of Schizophrenia

What is the percentage of the lifetime risk of schizophrenia in the general population?

1%

What were the findings of the identical quadruplet girl study by Rosenthal et al (1963)?

Showed varied ages of onset and fully developed schizophrenia.

What did Gottesman (1991) find about concordance rates?

Concordance rates between MZ twins was 48% but ONLY 17% for DZ twins.

What did Gottesman and Bertelsen (1989) find about people whose parents had an identical twin with schizophrenia?

People whose parents had an identical twin with schizophrenia had a 17% chance of being schizophrenic themselves.

What did Tienari et al (2000) find about biological mothers with schizophrenia?

6.7% of adoptees whose biological mother had schizophrenia also developed the disorder, compared to 2% of adoptees born to non-schizophrenic mothers.

What did Heston (1966) find about adopted children?

10% of adopted children developed schizophrenia, thus showing the role of genes as a genetic risk.

What did Kety et al (1994) find about children whose biological mothers were linked with schizophrenia?

Studied 150 children born in 1935 to 1945 whose biological mother was linked with schizophrenia; even though the patients were adopted, the diagnosis was still made.

What does Epigenetics look at?

Gene expression can be affected by the environment, e.g. diet, toxins, stress, etc.

How do genes work with environemental influences?

The genes are switched on or off by environmental influences and can be passed on to future generations.

What does the Diathesis Stress Model suggest?

The cause of an illness is both genetic and environmental.

What effect can Drugs have on Schizophrenia symptoms?

Drug treatments can reduce symptoms such as hallucinations.

What does Genetic Screening allow?

Genetic Screening could show who is more at a higher risk, allowing for early intervention and modification, e.g. counselling.

What's a strength of Genetic Explanation?

Multiple studies have found that genetically closer relatives of individuals with schizophrenia show higher concordance rates.

What's a limitation of Genetic Explanation?

That genetic explanations adopt a nomothetic approach, treating all individuals with schizophrenia as though they are the same.

What effects can cultural bias have on Genetic Explanations ?

Schizophrenia is diagnosed more frequently in Western cultures, possibly due to cultural interpretations of symptoms and differences in diagnostic systems.

What are Ventricles?

Cavities that produce and transport cerebrospinal fluid

What does Cerebrospinal fluid provide?

Provides protection, buoyancy and chemical stability to the brain and spine.

What did Weinberger et al. (1979) find about ventricular size?

Reported that ventricular size was greater in a group of 58 individuals with chronic schizophrenia than the 56 in the control group of people with no symptoms of schizophrenia.

What did Andreasen (1988) find in their MRI scans?

Studied MRI scans of individuals with and without schizophrenia, and found that those with schizophrenia had ventricles which were 20% to 50% larger than in controls.

What is Cortical atrophy?

The loss of neurons in the cerebral cortex.

What did Vita et al. (1988) find in their CAT scans?

Used CAT scans to assess 124 individuals with schizophrenia and 45 control group participants and found that 33% of the individuals with schizophrenia showed moderate to severe atrophy.

What did Luchins et al. (1979) find about reversals?

Found that there was an increase in the frequency of 'reversals' in both the frontal and occipital lobes.

What is a strength of the structural abnormalities explanation?

Techniques such as MRI and CT scans allow researchers to directly observe and measure differences in brain structure between people with schizophrenia and those without.

What's an explantion that is supported by large-scale studies and meta-analyses?

Research reviews and meta-analyses have consistently found enlarged ventricles, especially in individuals with chronic or severe schizophrenia, across diverse populations.

What are structural abnormalities also linked to?

Enlarged ventricles that are also present in individuals with other mental health conditions, such as bipolar disorder and schizoaffective disorder.

Neurodegenerative or neurodevelopmental?

These abnormalities could be due to a combination of both — with early developmental issues impairing brain growth and then increasing vulnerability to later degeneration.