FUNCTIONS OF THE BRAIN. 66 



which in turn excite others, until at last a motor discharge 

 downwards of some sort occurs. When this is once 

 clearly grasped there remains little ground for keeping 

 up that old controversy about the motor zone, as to 

 whether it is in reality motor or sensitive. The whole 

 cortex, inasmuch as currents run through it, is both. All 

 the currents probably have feelings going with them, and 

 sooner or later bring movements about. In one aspect, then, 

 every centre is afferent, in another efferent, even the motor 

 cells of the spinal cord having these two aspects insepara- 

 bly conjoined. Marique,* and Exner and Panethf have 

 shown that by cutting round a 'motor' centre and so sepa= 

 rating it from the influence of the rest of the cortex, the 

 same disorders are produced as by cutting it out, so that 

 really it is only the mouth of the funnel, as it were, 

 through which the stream of innervation, starting from else- 

 where, pours ; X consciousness accompanying the stream, 

 and being mainly of things seen if the stream is strongest 

 occipitally, of things heard if it is strongest temporally, 

 of things felt, etc., if the stream occupies most intensely the 

 'motor zone.' It seems to me that some broad and vague 

 formulation like this is as much as we can safely venture on 

 in the present state of science ; and in subsequent chapters 

 I expect to give confirmatory reasons for my view. 



MAN'S CONSCIOUSNESS LIMITED TO THE HEMISPHERES. 



But is the consciousness lohich accompanies the activity of 

 the cortex the only consciousness that man has ? or are his lower 

 centres conscious as well ? 



This is a difficult question to decide, how difficult one 

 only learns when one discovers that the cortex- conscious- 

 ness itself of certain objects can be seemingly annihilated 

 in any good hypnotic subject by a bare wave of his opera- 

 common to talk of an ' ideational centre ' as of something distinct from the 

 aggregate of other centres. Fortunately this custom is already on the 

 wane. 



* Rech. Exp. sur le Fonctionnement des Centres Psycho-moteurs (Brus- 

 eels, 1885). 



f Ptluger's Archiv, vol. 44, p. 544. 



X 1 ought to add, however, that Francois- Fran ck (Fonctious Motrices, 

 p. 370) got, in two dogs and a cat, a different result from this sort of 'cir- 

 cumvallation.' 



