Age at the time of brain injury is generally considered an important determinant in recovery of function. The implication is that older individuals show less recovery. Existing data challenge this common notion, but suggest differential effects of brain damage in aged subjects. To assess these differences old rats were trained on a two-choice brightness discrimination, subjected to visual decortication, and retrained with nonreversed or reversed reinforcement contingencies. A significant reversal impairment established that sparing of function in aged rats was similar to that in adult rats. However, a significant reversal X brightness interaction suggested that the progress of recovery of function in aged rats is influenced not only by what is spared but also by whether the expression of what is spared is consistent with or antagonistic to competing innate response biases.