An adoption and a cross-fostering study of the Minnesota Multiphasic Personality Inventory (MMPI) Psychopathic...

Area of Science:

• Psychology
• Behavioral Genetics
• Forensic Psychology

Background:

• Antisocial behavior in adolescents is a complex issue with potential genetic and environmental influences.
• The Psychopathic Deviate (Pd) scale of the Minnesota Multiphasic Personality Inventory (MMPI) is often used to assess traits associated with antisocial behavior.
• Understanding the interplay between genetic predispositions and adoptive environments is crucial for intervention strategies.

Purpose of the Study:

• To investigate the relative contributions of genetic and adoptive parental factors to adolescent psychopathic deviate (Pd) scores.
• To examine the association between parental MMPI scores and offspring Pd scores in both biological and adoptive relationships.
• To explore potential moderating effects of adoptive parenting on the expression of genetic risk for antisocial behavior.

Main Methods:

• Two complementary studies were conducted: a comparative study of biological and adoptive parents with high/low Pd adoptees, and a cross-fostering design study.
• Participants included biological and adoptive mothers and their teenage adoptees, assessed using the MMPI.
• Statistical analyses compared MMPI scores between groups and examined genetic and adoptive correlations.

Main Results:

• Biological mothers of high-Pd adoptees exhibited significantly higher MMPI clinical scale scores compared to mothers of low-Pd adoptees.
• Adoptive mothers showed fewer differences, though higher scores on Pd and Hypomania scales were noted for mothers of high-Pd adoptees.
• Genetic correspondences were substantial for Harris-Lingoes subscales, with less correspondence between adoptees and adoptive mothers.
• The cross-fostering study confirmed the significant effect of the biological mother's Pd score on offspring, with only a trend for adoptive mother effects.

Conclusions:

• Genetic factors play a significant role in the development of psychopathic deviate traits in adolescents.
• While adoptive maternal personality traits may influence the attenuation of antisocial behavior, genetic predispositions appear more dominant.
• These findings highlight the importance of considering genetic influences when addressing adolescent antisocial behavior.