Chap. XXIX.J SPEECH AND THOUGHT. 617 



those in relation with the movements for Speech and for 

 Writing) are, of course, only parts, though probably dis- 

 tinct and extensive parts of the respective cerebral Centres 

 for Audition, Vision, and Kinaesthesis generally. Hence 

 spoken words may not be comprehended though other 

 sounds are ; and again, written or printed signs may not be 

 understood, though ordinary objects may be easily recog- 

 nized through sight-impressions. 



Concerning the precise functional relations of thd 

 Kinsesthetic Word-Centres with the corresponding parts 

 of the Visual and Auditory Centres nothing is at present 

 known — the writer, however, believes that they play little 

 or no part in Thought. One section of them is probably 

 called into activity principally at the instigation of stimuli 

 emanating from the Auditory Centre for the bringing 

 about of Articulate Speech, whilst the other section is 

 probably called into activity principally at the instigation 

 of stimuli issuing from the Visual Centre preliminary to 

 the production of the movements concerned in Writing. 



From this point of view the Kinaesthetic Centres would 

 be concerned more with the expression of Thought than 

 with the Thinking-process : their activity would only be 

 roused as Thought is about to translate itself into Action. 

 Thus, they may, perhaps, form the last outposts on the 

 side of ' ingoing ' currents, and be at the same time the 

 starting-points for * outgoing ' currents. This view is quite 

 harmonious with the fact that the processes taking place 

 therein are almost as devoid of conscious accompaniment, 

 and almost as irrecoverable in idea, as are the molecular 

 processes occurring in the Motor Centres upon which the 

 initial ' outgoing ' currents act. 



An attentive study of the mental defects resulting from 

 Cerebral Disease will, we think, be found to yield results 

 quite in accordance with the views above expressed. 



