INTELLIGENCE AND THE FRONTAL-LOBE - THE ORGANIZATION OF GOAL-DIRECTEDBEHAVIOR

Basic to the study of individual differences is the concept of ''gener al intelligence'' or Spearman's g. In this article we suggest that g i s largely a reflection of the control functions of the frontal lobe. A series of experiments investigates a phenomenon we call goal neglect: disregard of a task requirement even though it has been understood an d remembered. Subjectively it is as though the neglected requirement ' 'slips the subject's mind.'' Previously described in frontal patients, we show that goal neglect can also be seen in some members of the nor mal population. In line with conventional distinctions between control led and automatic processing, eliciting conditions for goal neglect in clude novelty, weak error feedback, and multiple concurrent task requi rements. Under these conditions neglect is linked closely to g and ext remely common after frontal lesions. Following many other models, we s uggest that behavior in any task is structured by a set of action cons traints or requirements, derived in part from verbal instructions and specified at multiple levels of abstraction. A frontal process of cons traint or requirement activation is fundamental to Spearman's g. (C) 1 996 Academic Press, Inc.