Executive functions and the frontal lobes: a conceptual view

Several problems in understanding executive functions and their relationshi ps to the frontal lobes are discussed. Data are then presented from several of our studies to support the following statements: (1) the examination of patients with focal frontal lobe lesions is a necessary first step in defi ning the relation of executive functions to the frontal lobes; (2) there is no unitary executive function. Rather, distinct processes related to the f rontal lobes can be differentiated which converge on a general concept of c ontrol functions; (3) a simple control-automatic distinction is inadequate to explain the complexity of control-automatic processes; (4) the distincti on between complex and simple tasks cannot explain the differences in funct ions between the frontal lobes and other brain regions; and (5) the most im portant role of the frontal lobes may be for affective responsiveness, soci al and personality development, and self-awareness and unconsciousness.