Mean percent correct responses on critical trials as a function of training period. Con, Unoperated controls; Rh, monkeys with bilateral ablations of the rhinal cortex; Remote, object discrimination problems learned 16 weeks before surgery or rest; and Recent, object discrimination problems learned 1 week before surgery or rest.Open triangle, Rh1; open diamond, Rh2;open circle, Rh3; open square, Rh4;filled triangle, Con1; filled diamond, Con2; filled circle, Con3; and filled square, Con4.