56 Effect of Alcohol on Psycho-Physiological Functions. 



Dodge and Benedict. The only explanation for this is that the experi- 

 menter noted on the first day the tendency of the subject to engage in a 

 series of rapidly following voluntary winks immediately after he began 

 counting backwards at the signal which was given. In taking the 

 records, therefore, it was made a rule to watch the subject closely and 

 to release the plate in the camera at a time when he seemed relatively 

 free from winking. As table 7 shows, this was only partly successful. 

 In period 2 on alcohol days the anticipatory lid movements were 

 entirely lacking in the second series of experiments and nearly so in the 

 Dodge and Benedict series. In the latter, only 2 records out of a possi- 

 ble 12 showed the voluntary lid movement previous to or with the 

 primary reflex as compared to the second period for the normal days 

 when only 2 records out of the 12 did not show the lid movements. 

 The records in figure 6 are, therefore, absolutely typical for lid reflexes 

 under normal conditions and for lid reflexes 40 minutes after the inges- 

 tion of 30 c.c. of absolute alcohol. 



The question is pertinent and naturally suggests itself whether the 

 voluntary lid movements have any influence upon the latency and 

 amplitude of the reflexes which follow them. Doubtless much more 

 material must be brought together before this question can be ade- 

 quately answered. However, from the data at hand some indication 

 may be obtained for this relationship. It is of course evident that in 

 many of the records, as for example F in figure 6, the combination of 

 the voluntary wink and of the reflex is such as to make it impossible to 

 measure the latter with any degree of certitude. Records A to E, 

 inclusive, figure 6, may, however, be measured satisfactorily. The 

 first point to be fixed upon is not the beginning of descent by the reflex 

 curve, but the place where the voluntary curve begins to change its 

 direction under the influence of the reflex. Determinations were made 

 as follows (see table 8) : 



In the normal records taken by Dodge and Benedict on Subject VI, 

 22 primary reflexes preceded or accompanied by voluntary lid move- 

 ments gave an average latency of 34.7 <r and an amplitude of 16.2 mm. 1 

 Eleven normal primary reflexes unaccompanied by voluntary lid 

 movement yielded an average latency of 42a-, with an amplitude of 

 12.4 mm. In the second series of experiments 26 normal primary lid 

 reflexes, preceded or accompanied by voluntary lid movements, yielded 

 an average latency of 31.7 a, with an amplitude of 11.5 mm. Forty- 

 four normal primary reflexes, not accompanied by voluntary lid move- 

 ments, yielded an average latency of 36.6 a, with an amplitude of 8.2 mm. 



It so happened that the available records for our subject were about 

 equally divided between the two conditions, and as a result of this 

 classification of the records, it appears that voluntary lid movements 



1 The position of the eyelid at the moment reflex closure begins is taken as the base line from 

 which to measure the amplitude in such records. 



