Effects of Enriched Environment and Visual Deprivation on Development of Brain in Rat

When new-born rats were exposed to enriched (EC) or impoverished(IC) environment for 30 days, the enriched experience rats developed greater cortical weight, lower AChE activity per unit weight, and higher BChE/ AChE ratio than their restricted littermates. Typical EC-IC differences in weight and in enzymatic activity were also found in rats kept in complete darkness, thus visual experience was not a necessary component of the EC condition that induced changes in occipital and other cortical regions. Visual deprivation affected chiefly the occipital cortex and the superior colliculi. The occipital cortex of the dark-raised rats showed lower weight, lower BChE/AChE ratio and higher specific AChE activity, but the superior colliculi of the dark-raised rats showed greater BChE/AChE ratio and lower specific AChE activity.