Patellar Reflex. 45 



certain to produce changes in the position of the leg in relation to the 

 stimulus apparatus. 



Since L and L', and A and A' were measured with two stimulus inten- 

 sities, there are eight products for each period of experimentation. The 

 effect of 30 c.c. of alcohol upon these various factors and their relation- 

 ship may be more clearly seen if they are given in diagrammatic form. 

 Figures 2 and 3 are plotted from the percentage effects of alcohol on the 

 latency and amplitude as given in section in of tables 3 and 4, the plus 

 percentages being above and the minus percentages below the base lines. 

 The light and heavy lines in both figures represent the first reflex pro- 

 duced by the 30-gram and 50-gram stimuli, respectively, (L in figure 

 2 and A in figure 3) and the light and heavy broken lines the second 

 reflex within the refractory phase (1/ in figure 2 and A' in figure 3). 



The latency curves in figure 2 follow, in general, the same course. 

 During periods 2, 3, and 4 (for 2\ hours after the alcohol) the patellar- 

 reflex latencies are above the base line, showing a very slight lengthen- 

 ing, except for I/, 30 grams, period 4. In two cases there was no change, 

 and in no instance was there a decrease in latency. With this subject 

 alcohol produced a more prominent lengthening in the latencies for the 

 reflexes from 30-gram than from 50-gram stimuli. In period 2 both L' 

 are less affected than L, but subsequently they seem to be more sensi- 

 tive to the effects of alcohol with both stimulus intensities. But the 

 data for the second reflex, particularly with 30-gram stimuli, are much 

 more fragmentary, since many times the A' was so small that the L' 

 could not be measured. This being the case, the probable correctness 

 figures were not computed. 



In periods 5 and 6, figure 2, all of the latencies exhibit a decrease, 

 this being less with the 30-gram stimulus than with the 50-gram stimu- 

 lus; here again L' with both stimulus weights shows the change in a 

 more marked degree than does L. Since, for reasons previously men- 

 tioned, the normal data in tables 3 and 4 are incomplete for periods 5 

 and 6, no great stress should be laid upon the striking changes indicated 

 in figure 2 for these periods. 



The effect of alcohol upon the four patellar-reflex amplitudes (see 

 fig. 3) is not so uniform as with the latencies. Although the scale 

 distance for the ordinates in figure 3 has been reduced to one-eighth 

 instead of one-fourth, still the curves do not lie close to each other. 

 A, 30 grams, and A, 50 grams, are fairly parallel, but at somewhat diff- 

 erent levels. The former shows a decreased amplitude in periods 2, 3, 

 and 4, and the greatest decrease at 5, where the latency (fig. 2) was the 

 shortest, with a change to slightly plus at period 6. For A, 50 grams, 

 we find an increased amplitude in periods 2 and 3, changing to a de- 

 crease more marked in degree in 4 and 5, and again to an increase in 

 period 6. The increased amplitude with the 50-gram stimulus in 

 periods 2 and 3 might easily result if the alcohol produced a greater 



