IB SL Psychology studies

• Bouchard and McGue (1981)


  chard and McGue (1981) - Investigated the heritability of personality traits in twins - Found that heritability estimates were moderately high for most traits, indicating a significant influence of genetics on personality - Highlighted the importance of considering both nature (genetic) and nurture (environmental) influences on behavior Flashcard: <front>Bouchard and McGue (1981)</front> -backed:A study that investigated the heritability of personality traits in twins, finding moderate genetic influence on personality
• Bouchard et al. (1990) – Minnesota Twin Study


  Landmark study that investigated the influence of genetics on a variety of psychological traits by studying identical (monozygotic, MZ) and fraternal (dizygotic, DZ) twins raised apart and together
• Bouchard et al 1990


  Twin study that investigates the relative influence of genetics and environment on human behavior, personality, and intelligence
• Bouchard et al 1990 - Twin Study Results


  Identical twins show high similarity, fraternal twins low; heredity estimates for IQ and personality traits; environmental influence is limited
• Method


  1. Extensive testing and interviews with both sets of twins

  2. Researchers assessed a wide range of traits, including intelligence (IQ), personality, interests, and social attitudes
• 1. HTT Gene


  Gene involved in the transport of serotonin
• Caspi et al. (2003) study


  • Examined the interaction between the 5-HTT gene and environmental stressors in the development of depression
  • Followed a cohort of over 1,000 individuals from New Zealand
  • Assessed their experiences of stressful life events and their genetic makeup concerning the 5-HTT gene