Effects of preweaning environmental enrichment on basilar dendrites of pyramidal neurons in occipital cortex: a Golgi study

The effects of postnatal environmental stimulation on the branching patterns of cortical dendrites were measured in rats. Pups were exposed to 4 daily multisensory enrichment sessions from days 10–24, while littermates were maintained in standard conditions. At 25 days of age, the brains were stained using the Golgi-Cox-Sholl method. Camera lucida drawings were made of the basilar dendritic trees from a total of 528 layer-III occipital cortex pyramidal neurons. A highly significant increase was found in number and length of segments from order 1–5 in the neurons from the enriched subjects.