Lid Reflex. 51 



The latent time of the lid reflex is the same as that for the patellar 

 reflex, with the technique used and for this subject. The average for 

 L is 35 cr. The stimulus interval was the same (0.5 second) for both 

 reflex arcs, and in both instances the V was longer than its respective 

 L. The average L' for the lid reflex is 41 <r, as compared with V ', 

 patellar reflex, 30-gram, 38 a. The identity in the latent time of the 

 two reflexes for this subject may not be considered as entirely acci- 

 dental, since Dodge 1 showed that in his own case, in which the wink 

 reflexes were quite uninhibited, the latent time of the wink reflex and 

 of the knee jerk were practically identical. No comparison is made on 

 the basis of refractory phase values. That the average amplitude with 

 the two reflexes in the data under consideration happened to be so 

 nearly the same has, of course, no significance and is purely an acci- 

 dental matter. 



There is a fairly regular decrease in the amplitude of the first reflex 

 (A). ^ The first record taken in a period usually showed the largest 

 amplitude, and the other three more regularly the smaller amplitudes. 

 Reference to table 5 shows that the average amplitude for the first 

 period is likewise usually greater than that for succeeding periods on the 

 same experimental day, and finally, that the average A decreases from 

 day to day. Beginning with 22.3 mm. for the first period on the first 

 normal day, which is the largest amplitude during the series, there is 

 a decrease to 6.5 mm. in the first period for July 3, the fifth experimental 

 day. The columns of average amplitudes for the normal days regu- 

 larly show a decrease. With the alcohol days there is an exception in 

 the case of period 1, but in general the amplitude decreased as shown by 

 the averages 7.0, 6.5, and 4.0 mm. for periods 2 to 6 of the three days. 



There is a tendency for a compensating rise in the amplitude of the 

 second reflex; for example, the normal day values for A', period 1 (see 

 table 6, section i), show amplitudes increasing in size (2.1, 3.0, and 4.3 

 mm.), while those for A decrease as previously noted. The amplitude 

 of the two lid reflexes, therefore, seem normally to approximate recip- 

 rocal relations with one another. The reduction in the amplitude of the 

 reflex contraction, due to the possibility that the subject became accus- 

 tomed to the stimulus, is of course favored by the use of consecutive 

 experimental days. In the case of Dodge and Benedict's psychopathic 

 subjects, 2 all of whom served on consecutive days, the reduction in the 

 amplitude of contraction is conspicuous in every case for A, while A' 

 shows a consistent increase. These A' values are, however, very 

 slight. 



The average mean variation for the latency in the case of the pro- 

 tective lid reflex is larger than with the knee jerk. The patellar reflex 

 gave an average mean variation of L 1.3, and L' 1.0 <r, without a 



1 Dodge, Zeitschr. f. allg. Physiol., 1910, 12, p. 44. 



2 Dodge and Benedict's report, p. 69. 



