106 Effect of Alcohol on Psycho-Physiological Functions. 



Notwithstanding the fact that the considerable difference in level of 

 the two curves in figure 12 and of the two groups in figure 13, particu- 

 larly for the post-tetanus section, can not be considered as entirely due 

 to alcohol, since the first period for normal and alcohol days also shows 

 a difference in level, the alcohol did produce an effect upon the tetanus 

 pulse. In figure 14, while the course of the curves is somewhat irreg- 

 ular, it is clear that the curves for periods 2 and 3 of the normal days 

 in the pre-tetanus, tetanus, and post-tetanus sections are, in general, 

 below the curve for the first period of normal days. This means that 

 the course of the pulse on normal days tended towards a retardation 

 following the first period, like that found by Dodge and Benedict for the 

 group of normal subjects, particularly on the pulse during the associa- 

 tion experiments. The condition after alcohol, as represented in figure 

 14, is in direct contrast to this. In the pre-tetanus division the first- 

 period curve, normal, for the alcohol days occupies the lowest level; that 

 is, the curves for periods 2 and 3 do not touch any lower point. The 

 curve for period 2 is decidedly above, showing an average duration of 

 98 as compared with 104 for period 1. In the tetanus division of the 

 figure, the curve for period 2 is below 1, showing a less rapid pulse during 

 the activity. Following the muscle tension there is but a slight drop ; 

 the curve crosses that for period 1 and remains above it during the 

 post-tetanus division. The curve for period 3 of the alcohol days tends 

 to be above that for period 1 in every section, thus showing a more rapid 

 pulse following the alcohol, a condition of definite contrast with the 

 normal days, when the heart rate was slower after period 1, notwith- 

 standing the fact that there was a preliminary difference in level be- 

 tween the two groups of days in the post-tetanus section. 



A summary of the durations of the pulse cycles by periods for both 

 the normal and alcohol days is given in table 18, each pulse-length rep- 

 resenting the average of the corresponding pulse cycles shown in table 

 17 for the respective periods on the normal and alcohol days. The 

 differences, calculated according to the usual method, are likewise in- 

 cluded in the table and the effect of alcohol on all periods taken together 

 is given in differences and per cent. It will be seen at a glance that the 

 differences for normal days are predominatingly plus, while those for 

 the alcohol days are, as a rule, minus. This is a restatement of what 

 was indicated in the curves in figure 14, t. e., that the pulse-length 

 increased after the first period on normal days and decreased after the 

 first period on alcohol days. The average normal differences deducted 

 from those for alcohol show the contrast or general alcohol effect. At 

 every point (see bottom of table 18) in the pre-tetanus and tetanus 

 divisions and with the single exception of the eighteenth pulse cycle in 

 the post-tetanus division, the sign is minus, indicating a shorter pulse 

 cycle (faster pulse rate) after the alcohol. The effect is most prominent 

 in the pre-tetanus division. Here the average for all the measured 



