PSYCHOBIOGENETICS - ADAPTED TOOLS FOR THE STUDY OF THE COUPLING BETWEEN BEHAVIORAL AND NEUROENDOCRINE TRAITS OF EMOTIONAL REACTIVITY

The adaptive response to environmental challenges involves both behavi oral and neuroendocrine adjustments. Several examples show that the be havioral and neuroendocrine responses to environmental stimulations, f ar from being independent, are frequently interrelated and/or coselect ed. The existence of such a coselection in genetically selected models provides an advantageous tool for the study of genetic influence on e motional reactivity and the mechanism of linkage between behavioral an d neuroendocrine traits. In particular, the study of the Roman rat lin es which have been selected for their performance in active avoidance behavior has allowed us to establish the respective role of genetic an d maturation factors in the reactivity of these animals to stress. Ind eed, the role of maturation in determining interindividual differences appears to be more marked in RLA than in RHA rats. The study of genet ic factors, which play a major role in shaping individual characterist ics of reactivity, may help, therefore, to elucidate the biological me chanisms coupling behavioral and neuroendocrine aspects of personality structure to emotional reactivity.