Postnatal Changes, Possibly Due to Learning, in the Guinea Pig Cortex

Abstract

The guinea pig is born with the adult colouring, with functioning sense organs, with surprisingly good motor coordination and vivacious behavior setting in only minutes after birth. The brain is about 35% smaller than in the adult, but its internal structure looks the same down to the level of the network of fibres and synapses. And yet, the guinea pig learns as readily as related species do (Jonson et al, 1975; Petersen et al, 1977) and we expect therefore structural changes to take place in its brain after birth perhaps to the end of the animal’s life. Such changes accompanying learning, neatly separated from the effects of development by the event of birth, should be more readily detectable in the guinea pig than in other species.