Chap, ii.] THE BRAIK 779 



of the body is carried out by the middle portions of the brain, 

 and on these the motor area must have its hold as well as on 

 the spinal mechanisms. 



The details of the nature of that hold are at present un- 

 known to us ; but it must be remembered that not all the 

 fibres passing down from the motor region, not all those even 

 proceeding from the densest and most clearly defined motor 

 areas, are pyramidal fibres. With the pyramidal fibres are 

 mingled fibres having other destinations, and some of these 

 probably pass to the thalamus and so join the great tegmental 

 region. Moreover the motor region must have close ties with 

 other regions of the cortex whence fibres pass to the pons to 

 make connections with the cerebellum. On the other hand, 

 the cerebellum is especially connected with what we may fairly 

 consider the afferent side of the spinal cord and bulb. These 

 facts must merely be taken as indicating the possibilities by 

 which the motor region is kept in touch with the great coordi- 

 nating mechanism ; it would be venturesome at present to say 

 much more. 



In an ordinary voluntary movement an intelligent conscious- 

 ness is an essential element. But many skilled movements 

 initiated and repeated by help of an intelligent conscious voli- 

 tion may, when the nervous machinery for carrying them out 

 has acquired a certain facility, (and in all the higher processes 

 of the brain we must recognize that, in nervous material at 

 all events, action determines structure, meaning by structure 

 molecular arrangement and disposition) be carried out under 

 appropriate circumstances with so little intervention of distinct 

 consciousness that the movements are then often spoken of as 

 involuntary. All the arguments which go to shew that the 

 distinctly conscious voluntary skilled movement is carried out 

 by help of the appropriate motor area, go to shew that the 

 motor area must play its part in the involuntary skilled move- 

 ments also. So that distinct consciousness is not a necessary 

 adjunct to the activity of a motor area. And it is worthy of 

 notice that some of these, in their origin, purely voluntary 

 skilled movements, which by long-continued training have be- 

 come almost as purely involuntary, are hampered rather than 

 assisted by being ' thought about.' 



Lastly, without attempting to enter into psychological ques- 

 tions we may at least say that the birth-place of what we call 

 the ' will,' is not conterminous with the motor area ; the will 

 arises from a complex series of events, some of which take 

 place in other regions of the cortex, and probably in other parts 

 of the brain as well. With these parts the motor area has ties 

 concerned not in the carrying out of volition, but in the genera- 

 tion of the will. So that, looking round on all sides, it is 

 obvious, as we have said, that the motor area is a mere link in 



