Genetic and environmental influences on human psychological differences

Area of Science:

• Behavioral Genetics
• Psychology
• Human Individual Differences

Background:

• Psychological research identifies five major domains of individual differences: cognitive abilities, personality, social attitudes, psychological interests, and psychopathology.
• Understanding the origins of these differences is crucial for psychological research.

Purpose of the Study:

• To discuss methodological errors in individual differences research.
• To introduce a framework for interpreting behavioral genetic studies.
• To review behavioral genetic findings across five major domains of human psychological differences.

Main Methods:

• Review of quantitative methods in human behavioral genetics.
• Analysis of criticisms of behavior genetic designs, including twin and adoption methods.
• Examination of theoretical schemes and empirical findings within each domain.

Main Results:

• Identification of common methodological errors in the study of individual differences.
• Presentation of a framework for interpreting contemporary behavioral genetic research.
• Review of behavioral genetic findings across cognitive abilities, personality, social attitudes, psychological interests, and psychopathology.

Conclusions:

• Virtually all reliably measured individual psychological differences are heritable.
• Behavioral genetics provides strong evidence for moderate to substantial genetic influence on human behavior.
• The findings underscore the importance of genetic factors in shaping diverse psychological traits.