Certain personality traits known as cognitive styles are partially determined by genetic factors, which may account for some inherited similarities in political ideology, according to a twin study published online in Political Psychology.
Cognitive styles are elements of personality related to how people process information. The dimensions of cognitive style that have received the most attention from psychologists are need for cognition, finding challenging cognitive tasks inherently satisfying and desirable, and need for cognitive closure, finding ambiguous or uncertain situations unpleasant and undesirable. Both dimensions are closely tied with political orientation. People who score highly in need for cognition are likely to be politically liberal, whereas those who score highly in need for cognitive closure tend to be politically conservative.
Political orientation has been found to be influenced by genetic factors, as well as by one’s environment, but it has not been known whether differences in cognitive style are also partially genetically determined.
A team of researchers led by Aleksander Ksiazkiewicz, of the University of Illinois at Urbana-Champaign, used data from a twin study to examine the genetic components of cognitive styles, and their relationship with political orientation. In a twin study, the extent of similarities and differences are compared between pairs of monozygotic (MZ or identical) twins, who share 100% of their genetic code, and dizygotic (DZ or fraternal) twins, who share an average of 50% of their genetic code. Traits on which MZ twins are more similar to one another than DZ twins have a stronger genetic component. In this study, twins were assessed for both cognitive styles, as well as for a variety of political attitudes.
Both dimension of cognitive style were found to be significantly genetically inherited, with about 40% of differences in need for cognition and 37% of differences in need for cognitive closure attributed to genes versus environment. Also important, the correlations between cognitive styles and political ideology were almost entirely explained by genetic factors, indicating that the relationship between cognition and politics may exist because both are influenced by a shared set of underlying genetic causes.
The study authors conclude that cognitive styles are partially passed on genetically, and that their influence on political ideology is largely explained by genetics. These results add force to questions about the extent to which family similarities in political orientation are passed on genetically rather than by instruction from parents to children. When we try to explain the interface between personality and politics, this study suggests that genes are an important part of the equation.