DISCRIMINATIVE RESPONSES TO VISUAL STIMULI 



483 



This type of distribution may be explained on the hypothesis 

 that between the retina and the muscles of the hand are several 

 distinct systems of neural arcs of varying "length," and that 

 under favorable conditions of receptiveness of the organism, 

 the "shorter" ones may be brought into operation; while under 

 less favorable conditions the impulse must pass over certain of 



25 



4547 



(620 25 



SO S3 



25 



FIG. 5. PERCENTAGE DISTRIBUTION OF REACTION-TIMES OP SUBJECT M 



Ordinates, percentages of reactions. Abscissae, time in units of 0.01 second. 



Graph 9. Light line, 893 left hand reactions under condition B\. 



Graph 9. Heavy line, 893 left hand reactions under condition D\. 



Graph 10. Light line, 893 left hand reactions under condition B\. 



Graph 10. Heavy line, 896 left hand reactions under condition -B 2 . 



Graph 11. Light line, 894 right hand reactions under condition Bi. 



Graph 11. Heavy line, 897 right hand reactions under condition D\.. 



Graph 12. Light line, 894 right hand reactions under condition Bi. 



Graph 12. Heavy line 895 right hand reactions under condition B z . 



Vertical lines indicate averages. 



