Organization of the Multiple Endocrine Responses to Avoidance in the Monkey

In the presentation of an interpretation of the findings in the present study a number of general issues have been discussed. The findings suggest that the scope of psychoendocrine responses is remarkably broad. The findings also suggest that the multiple hormonal responses to avoidance are organized on an over-all basis. Some specific characteristics of this organization were suggested. The possibility that the multiple psychoendocrine responses were largely oriented to promote a “catabolic-anabolic” sequence of events in energy metabolism was suggested. The general importance of temporal factors in endocrine regulation was emphasized. Some basic similarities between the organization of endocrine, autonomic, and skeletal-muscular regulation were suggested--particularly with regard to the principle of a coordinated balance between opposing and cooperating forces. A number of limitations and critical questions concerning the present study were emphasized and some possible ways in which the concepts developed in this study might be further tested experimentally were discussed. The one aspect of the present study which may deserve emphasis above all the others is simply the point that recent methodological developments have now made the concept of endocrine “organization” accessible to experimental study. Whether the more specific formulations suggested, such as those involving the “catabolic-anabolic” pattern or the principle of “reciprocal-inhibition” in endocrine regulation, should eventually prove valid is not the main issue at present. What is most important is that the concept of endocrine regulation as organized or coordinated on a broad “over-all” basis--not only in relation to psychological stimuli but to other stimuli as well--is pursued in future experiments. The validity of this concept cannot be decided at present by argument, but only by new experiments carefully designed with this particular objective in mind. Further experiments on isolated endocrine systems, with the conventional measurement of one hormone or one hormonal class at a time, cannot provide the needed insight into the question of endocrine organization as a whole. Achievement of this objective almost certainly requires a movement toward more studies of an increasingly broad range of concurrent hormone measurements so that patterns and interrelationships between the many endocrine systems can be defined. In the design and conception of such experiments, it seems likely that useful clues may be provided by current knowledge of the metabolic effects of hormones, on the basis that organization of endocrine function at the “metabolic” and “regulatory” levels must almost certainly be closely linked. Some recent experience in our laboratory has also suggested some other factors that may have practical implications for future work in this direction. The final paper, therefore, will be devoted to a review of some possible sources of useful guidelines for future attempts to extend the approach developed in the present study beyond the psychoendocrine field.