PLAN OF THE INVESTIGATION. 13 



The following neuro-muscular processes were investigated in relation 

 to the effects of alcohol: 



( 1 ) Simple reflexes : 



(a) Lumbar arc. The patellar reflex, its latency and extent 

 of contraction as measured by quadriceps thickening, 

 with indication of its refractory period. 



(6) Cephalic arc. The protective lid-reflex to noise stimulus; 

 its latency, extent of movement, and refractory period. 



(2) Complicated reactions cortical arcs : 



(a) Eye-reactions to suddenly appearing peripheral visual 



stimuli. 



(b) Adequate speech-reactions to a series of 24 visual words. 



(3) Free-association reactions. Latency, character of the response, 



and concurrent pulse-changes. 



(4) Memory. Learning a normal series of 12 significant but uncon- 



nected words. 



(5) Sensory threshold to Faradic stimulation. Method of Martin. 1 



(6) Motor coordination: 



(a) Speed of the reciprocal innervation of the middle finger. 



(6) Speed and accuracy of eye-movements in looking from one 



point of fixation to another in the same horizontal 



plane through an arc of 40. 



(7) In addition to the neuro-muscular processes of the cerebro-spinal 



system, the autouomic system was investigated in the 

 peculiarly significant pulse-rate. Throughout the 

 experiments pulse was recorded either continuously or 

 at such intervals as the changing conditions seemed 

 to warrant. 



PRINCIPLES OF SELECTION OF THE EXPERIMENTAL PROCESSES. 



In several respects this group of experimental measurements repre- 

 sents a conscious departure from traditional methods for the investi- 

 gation of the effects of foods or drugs on man. The fundamental 

 principle of their selection was the attempt to secure a group of syste- 

 matically coordinated measurements. Instead of studying the effect 

 of alcohol on special, isolated, more or less arbitrarily chosen processes, 

 we have tried to bring together systematically coordinated data cover- 

 ing the most fundamental aspects of neuro-muscular action. 



It may be objected that in the end several investigations of different 

 processes, even though the latter are somewhat arbitrarily chosen, 

 would be as useful as a single investigation of coordinated processes. 

 It would seem that if unrelated investigations are sufficiently numerous 

 and sufficiently varied, they must finally furnish data for the most 

 extensive correlations. This would undoubtedly be true provided the 

 experimental material were obtained by comparable techniques on the 

 same subjects. Such conditions, however, could scarcely be realized, 

 except in carefully organized series like the present. Even under the 



1 Martin, Measurement of Induction Shocks, New York, N. Y., 1912. 



