Strategy application disorder: the role of the frontal lobes in human multitasking

Strategy application disorder is a term used to describe a pattern of defic its, usually associated with frontal lobe dysfunction, where people show di sorganisation, absentmindedness and problems with planning and decision mak ing in everyday life despite normal performance on traditional neuropsychol ogical tests. It is argued that the prototypical situation which presents p roblems for these cases are those which require multitasking, and although good cases are rare in the literature, those that do exist show a character istic neuropsychological pattern. Moreover, this pattern is confirmed in re cent group studies of multitasking and of the relationship between multitas king tests (such as the Six Element Test), failures in everyday life and ot her neuropsychological measures. At present the evidence suggests that the potential frontal brain regions most implicated in multitasking are the ant erior cingulate; B.A. 10 and immediately adjacent areas; and the right dors olateral prefrontal cortex, with each making a unique contribution to diffe rent aspects of performance. Furthermore, recent studies show striking diss ociations between performances on multitasking tests and two of the most co mmonly administered measures of executive function: the verbal fluency test and the Wisconsin Card Sorting Test, which sets a minimum level for a frac tionation of the executive syndrome in humans.