ABSTRACT
This chapter explains to a methodological aspect of the curare literature, namely, the influence of respiratory procedures employed in the maintenance of curarized rats. It explains the conditioning of cardiovascular responses in curarized rats. When research on learned control of the viscera first began to appear in the literature, the Zeitgeist, reflecting centuries of prejudice against the voluntary status of visceral responses, demanded evidence that the reported autonomic changes were not an artifact of "true voluntary" somatomotor activity. Since the characteristics of such true voluntary responses have not been made explicit, the difficulty of proving that cardiovascular responses are members of this class is insurmountable. In spite of the difficulties experienced in replicating many of the operant cardiovascular phenomena reported in the literature it must nevertheless be conceded that such phenomena exist. Weight factors associated with heart rate and blood pressure point to the advisability of grouping subjects within a narrow weight range and of avoiding extreme weights.
