144 



Effect of Alcohol on Psycho-Physiological Functions. 



In connection with the post-stimulation pulse acceleration reported by Dodge 

 and Benedict in their association experiments, some account should be taken 

 of the respiration phase. As stated by them (page 196 of their report) respi- 

 ration records were incorporated with the association pulse curves. These are 

 indicated in their illustrative figure 30 (page 195) by the long broken lines in the 

 record. These must not be confused with the very regular short dotted lines 

 which are the control time. In the discussion of the association pulse no 

 account seems to be taken of the respiration records. Sample association 

 pulse records were selected for each of the normal subjects, and these were 

 prepared by scratching with a stylus a dot at the beginning of each inspiration. 

 (The pointer of the respiration recorder was in contact with the drum during 

 inspiration.) These dots were clearly marked and could easily be counted. 

 The records, 8 in number, were then placed one above the other, so that their 

 stimulus columns formed practically a straight line. A cord was stretched 

 along the line so as to represent as nearly as possible the stimulus point of all 

 the records. This cord was marked S. Other cords were placed parallel to 

 S on both sides at distances of 5 centimeters, which represents the duration of 

 1 second. The dots representing the beginnings of inspiration were then 

 counted and recorded. The results are given in table 32. 



Table 32. — Relation of respiration phase to association pulse. 



1 Total number of inspirations counted 1,111. It required 10 seconds for the kymograph drum 

 to complete one revolution. 



According to the statement of Dodge and Benedict in table 13 (p. 114) the 

 average reaction time in these experiments was 2.16 seconds. There was 

 therefore a marked tendency for inspiration to occur or at least to begin after 

 the stimulus word and previous to the reaction, since the percentages 12.6 and 

 18.6 are largest at this section of the table. The smallest percentage of inspira- 

 tion occurs during the 1-second interval following the reaction. This same 

 relationship of respiration to the association experiment is logical. Prepara- 

 tory to reacting by vocalization the subject will naturally inspire and will tend 

 to hold the breath until he reacts. The vocalization constitutes the first 

 phase of the expiration. If the subject in this experiment tended to have in 

 any degree sinus arrhythmia, there would be a more or less rapid pulse from 

 this cause alone during and just after the reaction which would tend to be 

 counted as pulse acceleration and due to the stimulation word of the associa- 

 tion experiments. It therefore seems probable that the post-stimulation 

 acceleration is due in part to the stimulation of the vagus by inspiration as 

 well as the word stimulation of the experiment; this respiratory influence ap- 

 plies also to the post-tetanus phase of the tetanus pulse records of Subject VI. 



V 



