L5

• What is the focus of behavior genetics?

  Study of genetic contributions to behavior
• What do family studies in behavior genetics examine?

  Variation among individuals on a characteristic
• How do twin studies contribute to understanding heritability?


  By comparing identical and non-identical twins
• What is the significance of Gottesman's family study of schizophrenia?

  It suggests a high genetic component in schizophrenia
• What percentage of non-identical twins develop schizophrenia compared to siblings?

  17% for non-identical twins
• What limitation is noted in family and twin studies?

  They do not measure environmental factors
• What did Heston's study of adoptees reveal about schizophrenia?

  10.6% diagnosed with schizophrenia later
• How does the design of Heston's study contribute to its findings?

  It shows the impact of biology on schizophrenia
• What are the two main approaches to studying the brain and genes?

  Brain imaging and genetic association studies
• What do brain imaging studies measure?

  Brain structure, functioning, and connectivity
• What is the role of the hippocampus in mental health?

  Links memory with emotional context
• How does the prefrontal cortex relate to depression?

  Involved in planning and decision making
• What is the function of the hypothalamus?

  Regulates hormones and stress response
• What brain region is linked to psychosis?

  Thalamus, relaying sensory information
• What is the relationship between hippocampal activity and visual hallucinations?

  Reduced activity linked to visual hallucinations
• What do genetic association studies focus on?

  Presence of specific gene variants in samples
• How many genes do humans have?

  20,000 to 23,000 genes
• What are polymorphic genes?

  Genes with different variants in the population
• What is the significance of risk alleles in mental health?

  Associated with increased risk for disorders
• What did Lee et al. (2019) identify regarding mental disorders?

  Three clusters of related mental disorders
• What is a limitation of brain imaging studies?

  Causal effects can only be implied
• What do G x E studies examine?

  Interaction between gene variants and environment
• What did Caspi et al. (2003) study focus on?

  Variants of a serotonin transporter gene
• What is the role of epigenetics in mental health?

  Experience alters gene expression affecting behavior
• What is the focus of behavioral epigenetic studies?

  Effects of early life stress on gene expression
• What did Rutten et al. (2017) find in military personnel?

  DNA methylation changes linked to PTSD symptoms
• How do epigenetic changes affect gene expression?

  They can switch genes ON or OFF
• What conclusion can be drawn about genes and mental health?

  Genes and environment interact in complex ways