Rat brain: Effects of environmental enrichment on wet and dry weights (1969)

Bennett, E. L., Rosenzweig, M. R., Diamond, M. C.

Abstract

Wet weight of rat cerebral cortex was increased by exposure to an enriched environment [10 or 12 animals in large cage with toys], as compared with standard colony [2 or 3 animals in small cage] or impoverished conditions [single-housing].