226 BRAIN MECHANISMS AND LEARNING 



To be sure, on the basis of what inechanisnis docs the given combina- 

 tion, rather than any other out ot the niilhons of possible combinations of 

 excitations developing in the cellular elements of the central nervous 

 system, become integrated? 



On the basis of what mechanisms is a very dehnite end effect of adapta- 

 tion chosen and fixed out of the many probable end effects of adaptation, 

 this end effect being precisely the one which exactly corresponds to the 

 aggregate of the afferent influences affecting the organism at the given 

 moment ; 



We have become convinced that the key to the solution of these 

 problems lies in the extremelv fme and multihM"m processes of accumula- 

 tion of afferent information from the external and internal environments 

 of animals and man. This is followed by a dynamic interaction and 

 synthesis of this afferent information and, on the basis of these processes, 

 one of the most intimate processes of any form of conditioned behaviour 

 — the formation of the complex integrations of the effector apparatus. 

 This process truly deserves the picturesque designation given to it at one 

 time by our teacher Pavlov who named the afferent tunction of the brain 

 the 'creative' function. 



We see that it is indeeci 'creative' if we take into account the enormous 

 number of qualitatively heterogeneous afferent stimulations acting on the 

 organism at each given moment and if we adci to this that for man it 

 infallibly ends in what may be psychologically termed the formation of 

 the 'intention' of action. 



Many physiological factors contribute to this remarkable process. 

 Here we may include the rule oi coiii'frociicc of heterogeneous afferent 

 stimulations in the selfsame element of the stem reticular formation 

 (Fessard, 1958; Moruzzi, 1958; Amassian, 1958), the activating effect of 

 this system on the cortical level of elaboration of the afferent signals 

 (Moruzzi and Magoun, 1949), the integrating action of the frontal 

 divisions of the cerebral cortex on this synthetic process (Shumilina, 1944; 

 Anokhin, 1949) and, lastly, the controlling action of the cerebral cortex 

 on all the subcortical and spinal entering elements for the afferent impulses 

 (Anokhin, 1949; Livingston, 1958). All the above, put together, serves 

 the highest synthesis - the formation of the conditioned bond! 



Application oi' die term 'creative' to this process does not exclude the 

 fact that all its details, as well as the process as a whole, are structurally and 

 physiologically determined and, consequently, may become the subject 

 of a strictly objective scientific analysis. 



This latter proposition is illustrated by the fact that it is precisely the 



