74 PSYCHOLOGICAL EFFECTS OF ALCOHOL. 



Taking all these facts into account, the change of sign in the effect 

 of alcohol on the lid-reflex of these two subjects demands further scru- 

 tiny. It is conceivable, in the first place, that the change in sign may 

 be accidental. But the data seem too consistent for such an inter- 

 pretation. One must assume as probable that the facts indicate a 

 real exception to the rule. Any evidence to the contrary must bear 

 the burden of proof. In the second place, it should not be overlooked 

 that the normal difference values for Subject X are based on a single 

 normal day. While this violated both the requirements of our statis- 

 tical theory, and our practice in other cases, it seemed unavoidable in 

 the case of Subject X, who could ill afford time for further experiments. 

 In the case of Subject IV the records of two normal days are available, 

 but the relatively small amplitude of reflex movement on the second 

 day, combined with the relatively large amplitude in the first period 

 of the first normal day tends to disturb the distribution of the results 

 in the same direction as it is disturbed in the case of Subject X. The 

 effect was to exaggerate the importance of the initial sensitivity to the 

 stimulus. The average normal difference (av. 1-2, 1-3, 1-4, 1-5) 

 is consequently exaggerated, and the expression of the effect of alcohol 

 (alcohol difference minus normal difference) is doubtless too high. 

 Inspection of the unelaborated averages in the case of both Subjects 

 X and IV indicates that the effect of alcohol on the lid-reflex was in 

 fact not quite as great as the elaborated differences indicate. It may 

 be questioned, then, why we allow the misleading difference values to 

 stand. Following our statistical rule, we are bound to include all 

 computed values in the total, where accidental variations such as these 

 should theoretically tend to balance. Our special interest in these 

 individual cases is not because of any effect that they have on the 

 general tendency. It is chiefly the question whether they could be 

 interpreted as genuine exceptional cases of facilitation of a reflex by 

 alcohol. From the data at hand, this might be doubtful in the case of 

 Subject X. It seems especially clear, however, in the case of Subject 

 IV, where there is a conspicuous increase in the amplitude of the reflex 

 lid-movement immediately following the ingestion of alcohol. In both 

 cases one might suggest a third hypothesis. In view of the trained 

 inhibition of the reflex in both subjects, in Subject X by training in 

 shooting, and in Subject IV by training in football, it seems probable 

 that the trained inhibitions are the first to feel the effects of alcohol. 

 There are analogies enough in the succeeding chapters to give this 

 hypothesis plausibility. This is another of the special problems that 

 would seem to deserve direct experimental investigation. 



(VI) The total result of all these data indicate that as in the patellar 

 reflex so also in the lid-reflex, moderate doses of alcohol tend to depress 

 the excitability of the reflex arc. 



