SIMPLEST NEURAL ARCS. 73 



the possibility that the alcoholic depression of the reflexes which follow 

 its ingestion within our experimental sessions may operate to conserve 

 reflex excitability. They emphasize the importance of experimenting 

 over much longer periods than was provided for in this research. If 

 the alcoholic depression of excitability may operate to facilitate recu- 

 perative processes, or even to conserve against normal fatigue, it 

 would throw new light on the gross differences in clinical accounts of 

 the reflexes of alcoholics. 



(V) Two conspicuous exceptions to the generalization that alcohol 

 tends to depress the lid reflex occur in Subjects X and IV. In both 

 these subjects there is an unambiguous change of sign in the effect of 

 alcohol. In both cases the reflex latency is decreased and the ampli- 

 tude of the response is increased. That is, in both these subjects 

 alcohol facilitates the reflex. 



An inspection of the data of these subjects will show that in both 

 cases the amplitude of the normal lid-reflex is conspicuously small. 

 The extreme amplitude of lid-movement for subjects X and IV is 

 2.2 mm. and 4 mm. respectively. And these values are found only in 

 the very first periods of the first session. In other periods the ampli- 

 tude of the lid-movement of Subject X fails to reach even 2 mm. In 

 no series of this subject, moreover, is the response to the second stimulus 

 of sufficient amplitude to permit measurement of its latent time. In 

 other words, in response to both the first and the second stimulus the nor- 

 mal lid-reflex of Subject X is extremely refractory. This was naturally 

 noticed by the experimenters during the preliminary tests and led to 

 the following disclosures: All the reflexes of Subject X are either 

 entirely lacking or extraordinarily refractory. The knee-jerk could not 

 be produced regularly without reinforcement by hammers up to 100 

 gm. in weight falling 40 cm. The Achilles reflex was present, but was 

 apparently as refractory as the knee-jerk. The toe-reflexes were 

 reported to be entirely lacking. They were not reinvestigated. With 

 special reference to his lid-reflex to noise, Subject X reported being 

 thoroughly accustomed to the use of firearms and trained to keep his 

 eyes open as he shoots. The relative importance of nature and training 

 in this case can not be determined from the data at hand. It is clear, 

 however, that both factors are present. It should be noted in passing 

 that both Subjects X and IV differ from the refractory subject pre- 

 viously described by Dodge 1 in having a normal reflex latency. Only 

 the amplitude is abnormal. Much the same is true of the lid-reflex 

 of Subject IV that was true of Subject X. In this subject, however, 

 the refractoriness of the lid-reflex seems to be entirely artificial, con- 

 nected with his football training. Evidence for a rapid adaptation 

 process in both subjects is found by comparing the first with the second 

 period on the first normal day of each. 



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



