ix MID- AND INTEE-BEAIN 511 



limbs. Tactile stimuli evoked complex movements as well as 

 simple reflexes. 



It would be of the greatest interest to obtain a long survival 

 after complete decerebration in monkeys, in order to see how 

 far the phenomena of deficiency can actually be modified. 



H. Munk put forward a number of ingenious objections to 

 the effect that all the phenomena described by Goltz in the 

 brainless dog can be explained as simple reflexes, not necessarily 

 accompanied by any psychical activity. He holds that the sense 

 centres by which we are normally brought into relation with the 

 external world are protected against the abnormal and injurious 

 effects of certain peripheral stimuli by a mechanism which evokes 

 ordinary reflex movements, unaccompanied by sensations, which 

 ward off or remove the stimuli from the nerve-endings, while at 

 the same time they can arouse sensations so that conscious and 

 voluntary movements co-operate to the same purpose. These 

 common protective movements, whose reflex centres lie below the 

 fore-brain, persist in the dog without cerebral hemispheres. 



In the next chapter we shall return to Munk's theory. Here 

 we need only point out that Goltz declines to consider the 

 brainless dog, which sleeps when replete, is restless when its meal 

 is delayed, and tries to bite the hand that teases it, as a mere 

 reflex machine, an insensitive automaton. If these complex acts 

 are unmistakable signs of wants, feelings, sensations in the 

 normal dog, why are they less so in the dog without a cerebrum ? 



Munk and those who agree with him show a tendency to 

 limit the material basis of psychical phenomena as much as 

 possible, and to ascribe them solely to the cerebral cortex, perhaps 

 with the object of facilitating the solution of certain problems. 

 Nevertheless the riddle of the "psyche" remains, whatever theory 

 of sensibility and consciousness is accepted. 



The theory of Loeb one of the most distinguished of Goltz' 

 pupils comes very near that of Munk. Starting from Munk's 

 position that consciousness is a function of memory, because when 

 memory is lost, as in fainting, deep sleep, and in stupor due 

 to certain poisons, consciousness is simultaneously suspended, 

 Loeb concludes that the prosencephalon is indispensable to 

 memory, and consequently that the brainless animal is an 

 automaton entirely destitute of personality or consciousness, but 

 he adds a reservation which does not seem important in view of 

 the experimental observations of Schrader and Goltz. Loeb 

 shrinks from going so far as to assume that the fore-brain is the 

 organ of consciousness. "The organ of consciousness may well 

 be the whole brain or the whole of the central nervous system so 

 long as it is connected with the fore-brain, and the latter may 

 be indispensable only in the activity of memory associations." 



A critical examination of this theory would take us too far 



