Adult and embryonic frontal cortex transplants after frontal cortex ablation enhance recovery on a reinforced alternation task.

Damage to the medial frontal cortex in rats results in a learning deficit on a reinforced alternation task. The rate of recovery from this deficit was accelerated by transplantation of either adult or embryonic frontal cortex, provided that a delay was introduced between injury and transplantation. The rates of recovery for both delayed embryonic and adult transplants did not differ from the undamaged group. In contrast, transplants of embryonic frontal cortex immediately after ablation did not accelerate the rate of recovery. The accelerated rate of behavioral recovery on the reinforced alternation task appeared to correlate with transplant survival.