motivational behavior is explained in the light of reflex theory by reference to : ( i ) pavlov 's concept of nerve center as an assembly of structures messing the same function , ( ii ) sherrington 's and magnus ' ideas about the hierarchical structure of the nervous system , ( iii ) author 's notion about the multistage arc of the unconditioned reflex , i.e. , an arc with many branches in its central path , each passing through the main integrative levels of the central nervous system , ( iv ) experimental facts of this laboratory and particularly concerning bidirectional conditioned connections .
C0004927
behavior
C0027763
structure of