Genetic Determinants of Emotional Behavior: Legal Lessons from Genetic Models

The past decade of neuroscience research has been dedicated to the elucidation of the genetic heritability of mental processes and the role of specific genes in their regulation. A long reluctance to tackle questions related to the molecular basis of behavior has been overcome; genetic technologies and approaches to the question have developed and expanded. Psychology, which historically belongs to the social sciences, became more and more connected to the biological sciences, not only on a neuroanatomical but also on a genetic level. By using animal models—rodents, in particular—the genetic basis of behavior has been examined in a large number of experiments.1 This Article attempts to summarize what we have learned from animal models, and suggests which critical questions still need to be answered if we are to further elucidate the relationship between genetics and behavior. We focus predominantly on the genetic determinants of stress-induced behavior, such as fear and anxiety, and we explain how these behaviors relate to aggression in rodents. Although convincing evidence demonstrates the role of genes in evolutionary conserved or species strains and gender-specific behavior, it has become increasingly clear that the gene-environment interactions shaping emotional behavior are extremely complex. The rules applying to these interactions seem to be diverse and flexible, enabling adaptation to the external demands of our social environment and the rigid rules of our legal system. Genetic abnormalities, however, may cause maladaptive behavior that significantly impairs the ability of that individual to integrate into the social system. A society’s capacity for emotion may even influence the evolution of social norms—and thus the law.