Dominance and submissiveness between twins. I. Perinatal and development aspects

Area of Science:

• Developmental Psychology
• Twin Studies
• Behavioral Genetics

Background:

• Understanding the factors influencing dominance and submissiveness within twin pairs is crucial for developmental psychology.
• Previous research suggested perinatal factors significantly impact twin dyadic dynamics.

Purpose of the Study:

• To analyze factors predicting dominance and submissiveness in a longitudinal study of 234 twin pairs.
• To investigate the influence of sex, birth weight, birth order, Apgar scores, and perinatal complications on twin leadership roles.

Main Methods:

• Longitudinal analysis of 234 twin pairs.
• Assessment of dominance and submissiveness through behavioral observation and potentially parent/self-report (details not specified in abstract).
• Statistical analysis to identify predictive factors.

Main Results:

• Boys exhibited more physical dominance; girls displayed more psychic dominance and acted as spokespersons.
• Low birth weight, being second-born, or low Apgar scores showed a non-significant trend towards predicting submissiveness.
• Perinatal asphyxia and hypoglycemia had a potential cumulative effect on submissiveness.
• Faster development and higher intelligence were associated with leadership roles within the twin pair.

Conclusions:

• Sex differences in dominance styles are evident in twins.
• While perinatal factors may play a role, their influence on submissiveness appears less pronounced in contemporary twin studies, likely due to improved neonatal care.
• Cognitive and developmental trajectories are significant predictors of leadership in twin relationships.