56 BULLETIN OF THE UNIVERSITY OF WISCONSIN. 



sustained by the intellectual faculties. The latter consequence 

 of brain fatigue is of chiefest concern to the student alike in his 

 immediate daily duties and in his future vocation, which will 

 for the most part require of him keen perception, accurate, ready 

 memory, and, above all, careful and judicious reasoning. From 

 what has gone before it must be apparent now that fatigue im- 

 pairs those cerebral conditions which are essential to normal 

 intellectual activity; and the most prominent effect of this in 

 the mental life is to render attention less concentrated and en- 

 during than when one is in good neural form, so to speak. 

 Any person who has endeavored to apply himself to arduous 

 undertakings when his resources have been too heavily taxed 

 knows that it is with great difficulty he can hold his mind to 

 the thing in hand, and he is likely not to succeed at all in the 

 attempt. As James has said, 1 one grasps at everything in or- 

 der to find relief from the object before him. At this time 

 ideas crowd into the focus of consciousness which in seasons of 

 mental vigor can be inhibited ; and the upshot of it is that dis- 

 traction ensues; the mind grows inaccurate and lethargic, and 

 arrives finally at a state which, lacking a better term, we may 

 name stupidity. 



From the point of view of neurology the dispersion of atten- 

 tion in cerebral fatigue is simply explained. It has already 

 been said that the co-ordinating, the regulative functions of the 

 brain are disturbed in neural depletion, and there attends this 

 condition a sort of independence of the various nerve centers 

 resulting in lessened subordination of irrelevant motor activities. 

 The individual does things that in better times he would be able 

 to inhibit. Now, the neural capacities essential for right phys- 

 ical co-ordination are, it seems, requisite as .well for mental co- 

 ordination ; and what renders one impossible will interfere also 

 with the proper action of the other Concentrated attention re- 

 quires the convergence of the mental powers upon one point, 

 with of course restraint of disturbing impulses; but as the in- 

 hibitory processes are less vigorous and constant in fatigue, 



l Psychology, Briefer Course, p. 225. 



