A Genetic Neuroscience Approach to Human Cognition

A large gap exists between behavior genetics and cognitive neuroscience, although psychologists feature prominently in both fields. Behavior genetics focuses on individual differences and, through sophisticated statistical modeling in twin and family studies, addresses the genetic and environmental contribution to variation in cognitive ability. Cognitive neuroscience tends to focus on species universals in brain function during specific cognitive operations, which are isolated by clever experimental design, and located in the time and (brain) space by modern imaging techniques. This paper describes the complementary approach of "genetic neuroscience" that integrates the study of cognition as an individual trait and the study of cognition as an universal process. It is argued that the intermediate phenotypes or "endophenotypes" of brain function and structure from neuroscience will boost the power of geneticists' association and linkage approaches to find the genes underlying differences in cognitive ability. Neuroscience, in turn, will profit greatly from successfully identified gene functions. Genes can provide insight in the "black box" between molecular events and cognition. They offer many opportunities to lay bare gene by environment interactions in the psychological laboratory. By reviewing some of the main issues in each field and summarizing the mutual advantages of collaboration between geneticists and neuroscientists we hope to mount further support for a complementary approach.