ABSTRACT
Among the clinical claims that have been made concerning the function of the intact frontal lobes are that within them are “centers” in which are organized perception and learning processes, together with the maintenance of direction of activity and goal seeking. Presumably, injury or surgical ablation of parts of the frontal lobe should lead to interference with these functions. Previous experimental studies of brain tumor and psychosurgery patients yielded no substantiation of these claims, but they still persist in many quarters partly because of the long tradition behind them and partly because it is much more difficult to disprove a hypothesis experimentally than to propose one. It is clear that pure tasks of each of these capacities can be constructed only with great difficulty since perception and learning enter into almost all mental tasks, and maintenance of set is a factor in all mental activity. Nevertheless, tasks can be found that may be regarded as dependent primarily on learning and relatively free of other psychologic functions. Similarly, tasks can be found for testing perception and mental set that are relatively free of other functions.
