Explainastions Flashcards
What is the primary focus of biological explanations of schizophrenia?
Genetic factors and their influence on the disorder
Biological explanations emphasize the role of heredity in schizophrenia.
What type of studies show a trend in schizophrenia among family members?
Family Studies
Family studies investigate the prevalence of schizophrenia within families.
What are the two types of twin studies used in schizophrenia research?
Monozygotic (MZ) and Dizygotic (DZ) twins
MZ twins share 100% of their genes, while DZ twins share 50%.
What is the concordance rate for MZ twins according to Gottesman and Shields (1966)?
42% me
The concordance rate for DZ twins is 9%.
What is the definition of heritability in the context of schizophrenia?
The extent to which the presence of a disorder is due to genetic variance in the population
Heritability indicates how much genetics contribute to the disorder.
What is the conclusion of Hilker et al.’s twin study regarding the heritability of schizophrenia?
Heritability of schizophrenia is 79.2%
This study included over 30,000 pairs of twins.
What do adoption studies help distinguish in the context of schizophrenia?
Genetic and environmental factors
They compare adoptive children to biological children.
What do genome-wide association studies (GWAS) identify in relation to schizophrenia?
Gene variants associated with the disorder
GWAS helps to find polymorphic genes that are more common in individuals with schizophrenia.
What does it mean that schizophrenia is a polygenic disorder?
It is likely the result of more than one gene
This indicates that multiple genetic factors contribute to the development of schizophrenia.
Fill in the blank: The concordance rate for DZ twins is _______.
9%
## Footnote
This low rate suggests a lesser genetic influence compared to MZ twins.
True or False: Schizophrenia is solely caused by one single gene.
False
Schizophrenia is influenced by multiple genes and environmental factors.
What is the relationship between certain alleles and schizophrenia?
Certain alleles may be responsible for neurochemical imbalances associated with schizophrenia.
This highlights the genetic influence on the disorder.
What can cause problems during cell division related to schizophrenia?
Errors during cell division can lead to duplications or deletions of DNA strands.
These errors may increase the risk of developing schizophrenia.
What is DiGeorge syndrome and its connection to schizophrenia?
DiGeorge syndrome involves the deletion of 30-40 genes from chromosome 22, which can lead to the development of schizophrenia.
This syndrome highlights a genetic factor linked to the disorder.
Which specific gene deletion is linked to schizophrenia in DiGeorge syndrome?
The deletion of the COMT gene is linked to schizophrenia.
The COMT gene codes for an enzyme that breaks down neurotransmitters such as dopamine.
What role does the neurotransmitter GABA play in schizophrenia?
GABA is an inhibitory neurotransmitter that may be associated with increased sensitivity in schizophrenia.
This suggests a complex interaction of neurotransmitters in the disorder.
What is the dopamine hypothesis in relation to schizophrenia?
The dopamine hypothesis states that brains of people with schizophrenia produce more dopamine than those without the disorder.
This theory links dopamine levels to the symptoms of schizophrenia.
What can cause an excess of dopamine in the brain?
Excess L-Dopa and differences in the number of dopamine receptors can cause increased dopamine levels.
These factors may contribute to schizophrenia symptoms.
Define dopamine.
Dopamine is a neurotransmitter that enables communication between neurons, allowing impulses to pass between cells.
It plays a significant role in many neurological functions.
Fill in the blank: The excess of dopamine is considered a cause of _______.
schizophrenia
True or False: Schizophrenia is solely caused by genetic factors.
False
What is the role of neurotransmitters in the context of schizophrenia?
Neurotransmitters like dopamine and GABA are involved in the biochemical imbalances associated with schizophrenia.
Their interactions are crucial in understanding the disorder.
What is the transmission of nerve impulses from one neuron to another called?
Neurotransmission
Neurotransmission involves both electrical and chemical signals.
What are the two ways neurons transmit signals?
- Electrical (within a neuron)
- Chemical (between neurons)
Chemical transmission occurs at the synapse.
How do neurotransmitters move across a nerve?
In vesicles until they reach the synapse
Vesicles release neurotransmitters into the synapse.
What happens to excess neurotransmitters after they are released into the synapse?
They are absorbed back into the presynaptic neuron
This process is essential for regulating neurotransmitter levels.
What role do enzymes play in neurotransmission?
Enzymes break down excess neurotransmitters
This prevents overstimulation of receptors.
What is the effect of neurotransmitters binding to receptor sites?
They activate the receptors
This initiates the transmission of the message to the next neuron.