240 PSYCHOLOGICAL EFFECTS OF ALCOHOL. 



depressor corresponds point for point with the effect of alcohol on the 

 reflex mechanisms of the cord and basal ganglia. The extent of the 

 reflex response was lessened and the latent time was lengthened. Hence 

 it should not surprise us that the cardio-inhibitory reflexes of the medulla 

 show similar effects of alcohol. 



The question as to why alcohol in moderate doses acts selectively on 

 the heart inhibitor rather than on the accelerator is one that property 

 belongs to general physiology rather than to this investigation. It 

 may be noted, however, that alcohol in this respect, as in others, appears 

 to follow its pharmacological relatives, ether and chloroform (Hunt 1 ). 

 Moreover, it seems that the inhibitor is in general more susceptible to 

 disturbing influences than the accelerator. It acts quicker and re- 

 sponds to less vigorous stimuli (Hunt, 1 Aulo, 2 Krogh and Lindhard 3 ). 

 But we expressly limit our generalizations as to the effect of alcohol on 

 pulse frequency to the dosage and other conditions of our experiments. 

 There is, indeed, some probability that the curve which represents a 

 direct proportion between the dose and pulse frequency for 30 and 45 

 c.c. would follow the same direction above and below these limits. 

 But our actual data are limited to our two doses; and theoretically 

 there is no guarantee that a cusp in the curve or a change in its direc- 

 tion might not occur at any point. In fact, Dixon 4 definitely voices a 

 common conviction that in the qualitative pulse-changes produced by 

 different doses, alcohol is unique. Moreover, if alcohol is a general 

 depressant, as our evidence shows, there is no reason why it should not 

 also partially paralyze the cardio-accelerator as well as the cardio- 

 inhibitor mechanism. Indeed certain of our results, viz, the relatively 

 large loss in rhythmic, respiratory, and experimental changes in the 

 pulse variability, as compared with the slight acceleration changes, 

 suggest that the effects of a decreased irritability of the cardio-inhibitory 

 center are contaminated, even in our data, by a decreased accelerator 

 tone. 



That under our experimental circumstances the inhibitor mechanism 

 suffers the greater depression seems to be clear from our data. But 

 different circumstances might supposedly alter the balance of the 

 effects in the two systems so as to produce no change at all in the 

 pulse-rate or even to produce a pulse retardation instead of an accel- 

 eration after alcohol. Something of that sort apparently happened 

 in the case of Subject IV in the association-pulse after dose B. The 

 commonly accepted doctrine that alcohol retards the pulse of fever 

 patients may be another case to the point. Mosso and Galeotti 5 

 remarked the similarity of the alcohol pulse to the fever pulse. It 

 seems plausible that if the cardio-inhibitor center has already been 

 notably depressed before the alcohol is given, its further depression 



t, Am. Journ. Physiol., 1899, 2, p. 395. 

 2 Aulo, Skand. Archiv f. Physiol., 1911, 25, p. 347. 

 3 Krogh and Lindhard, Journ. Physiol., 1913, 47, p. 120 (esp.). 

 'Dixon, Journ. Physiol., 1907, 35, p. 346. 

 6 Mosso and Galeotti, Lab. Sci. Int. du Mont Rosa, 1903. (Published 1904.) 



