Cardiovascular responses to avoidance conditioning in the dog: Effects of alpha adrenergic blockade

Laboratory dogs were trained to press a response panel to postpone shocks during daily one-hour avoidance conditioning periods. Each dog was also confined in the experimental environment for 5 hours prior to the avoidance periods. Blood pressure and heart rate were monitored continuously during these experiments from chronically indwelling arterial catheters. Extended training resulted in the emergence of a cardiovascular response pattern during the pre-avoidance interval characterized by gradual increases in blood pressure together with decreases in heart rate. Elevations in both blood pressure and heart rate were sustained during the avoidance periods. During sessions in which alpha adrenergic activity was suppressed by phenoxybenzamine, absolute levels of blond pressure were found to be lower than during control (non-drug) sessions, but a progressive rise in blood pressure continued to be observed during pre-avoidance. These results suggest that sustained cardiovascular responses during avoidance periods are associated with activation of the sympathetic nervous system, but that the gradual rise in blood pressure during pre-avoidance is due to other factors.     

Correlations of normality and nervousness with cardiovascular functions in pointer dogs

Methylphenidate, 0.5 mg/kg, injected intravenously, was used in 10 normal (A line) and 10 genetically nervous (E line) dogs in a blind-design experiment to aid in prediction, from cardiovascular recordings alone, of behavioral normalityversus nervousness. The prediction was 75 per cent correct, based on heart rate (HR), form of the electrocardiogram (EKG), pattern of sinus arrhythmia, and pattern of HR response to methylphenidate. Nervous dogs were found to have slower baseline HR’s, delayed return of HR to baseline after methylphenidate, greater occurrence of baseline EKG abnormalities and much greater frequency of these after methylphenidate. Degree of nervousness was found to correlate rather highly (1)negatively with baseline HR level, (2)negatively with speed of BP response, and (3)positively with frequency of some of the EKG manifestations. These data, indicative of a relative inertness of physiological functions of nervous pointer dogs compared with normal pointers, are consistent with the behavioral and some of the biochemical findings previously reported.     

Research support from the office of Naval Research

The operation of the Psychological Sciences Division of the Office of Naval Research is described briefly. Guidance is provided for prospective proposers of research to that division.     

JUST WAR THEORIES RECONSIDERED: Problems with Prima Facie Duties and the Need for a Political Ethic

This essay challenges a “meta‐theory” in just war analysis that purports to bridge the divide between just war and pacifism. According to the meta‐theory, just war and pacifism share a common presumption against killing that can be overridden only under conditions stipulated by the just war criteria. Proponents of this meta‐theory purport that their interpretation leads to ecumenical consensus between “just warriors” and pacifists, and makes the just war theory more effective in reducing recourse to war. Engagement with the new meta‐theory reveals, however, that these purported advantages are illusory, made possible only by ignoring fundamental questions about the nature and function of political authority that are crucial to all moral reflection on the problem of war.