lo Journal of Comparative Neurology. 



scious processes react on the sensory organs and modify their 

 functions. It is a famih"ar commonplace that the degree of at- 

 tention is very dependent on the feeling tone of a sensation. 

 Two points are to be noted here : first, that the greater number 

 of feelings associated with sense impressions liave a practical 

 value for the life of the individual and have so acquired an im- 

 pulsive connection with external attention without calling con- 

 sciousness into play ; and, second, that the very nature of feel- 

 ings involves intensity of the stimulus (summation, on one hand, 

 and irradiation, on the other,) so that this comes under the head 

 of intensity as above. But let us turn to another form of this 

 activity. I resolve to attend to the excitations of some sense 

 or, as we say, to keep eyes and ears open. This resolves itself 

 into a more or less fruitless attempt to accommodate the organ 

 voluntarily and results in for the most part ill-directed if not dis- 

 turbing oscillations in the tension of the organ. Thus when in 

 the night I strain the ear to catch a sound in no special locality I 

 become conscious of the fact that the tensor tympani and stape- 

 dius muscles are making castanets of my ears and audition is im- 

 peded rather than facilitated ; so when I strain if perhaps I can 

 make out another star in a vacant space I lose more than one 

 "dimension" before visible. One becomes conscious of a 

 sense of effort in various organs, even in such as have no direct 

 connection with vision and also of alterations in the somatic sen- 

 sations. These sensations of effort, then, seem to us to prove 

 the presence of attention, even voluntary attention, when there 

 is absolutely no attention, for it is idle to speak of attention 

 when nothing is attended to. It is only a cavil to say that in 

 the case indicated there is attention to the sensations of effort. 

 Such reasoning is an endless chain. When we really attend to 

 something in the sensory sphere it is some specially selected an- 

 ticipated thing. Even in the general case of listening for a 

 noise we reproduce in thought one noise after another in ad- 

 vance. " It will prove to be a creak, or a scratch, or the like." 

 Imagination meets the visual impression more than half way. 

 "Is it a dagger that I see before me?" We are looking for 

 something — our attention consists in the scrutiny of the content 



