238 BRAIN MECHANISMS AND LEARNING 



Structures at least, and the exact specification of where this occurs would 

 appear to be valuable information to collect (Galanibos and Sheatz). 



5. Anaesthetization profoundly modifies the brain response to click or 

 flash. Several waves disappear from the cortical record; the earliest one 

 persists as the well-known evoked response of the deeply anaesthetized 

 cortex. Furthermore the number of brain locations where responses 

 appear becomes smaller as the anaesthetic constricts activity into approxi- 

 mately the limits of the classical afferent pathway. 



6. Whereas several years ago we felt the evoked response variations 

 here under discussion might reflect the specific changes connected with 

 the formation of the 'temporary connection' we presently view them, in 

 agreement with many others (e.g. Voronin ct a\.), as more probably 

 related to attention, orientation responses and the like. This conclusion 

 does not at all diminish our interest in them, however, for the brain 

 processes they signify unquestionably underlie the one we originally set 

 out to study. The brain is somehow primed or prepared for the specific 

 event it undergoes when learning is achieved, and an exact definition of 

 the factors responsible for this is a necessary first step. 



CONCLUSION 



observation and experimental analysis are said to be of value only in so 

 far as they provoke a new and more comprehensive synthesis. If what has 

 gone before in this essay can be called an analysis it is surely a small and 

 imperfect one and the syntheses to be derived from it are merely specula- 

 tive questions. One may observe, however, that physiologists are perhaps 

 overly impressed by the learning abilities of man; deeply involved in the 

 search for an explanation for his unusual capacities they seem to reject the 

 thought that human learning almost surely represents merely an extension 

 and elaboration of a general capacity possessed by most living animals. 

 While the principles in operation may indeed work more efficiently or to a 

 more elaborate degree in man with his highly developed neocortex, it 

 seems only reasonable to assume that the same principles operate not only 

 to produce his learned reactions, but also to guarantee performance of his 

 unlearned respc^nses (e.g. breathing) and to make possible the learning 

 displayed by animals with simple nervous systems as well (but see Pantin, 

 p. 193 for an opposite view). It could be argued, in brief, that no important 

 gap separates the explanations for how the nervous system comes to be 

 organized during embryological development in the first place; for how it 

 operates to produce the innate responses characteristic of each species in 



