BACKGROUND: Lesions of the frontal lobes may impair the capacity of patients to control otherwise intact cognitive operations in the face of ambiguous sensory input or conflicting possible responses. OBJECTIVE: To address the question of whether focal lesions in different regions of the frontal lobes produced specific impairments in cognitive control. METHODS: We evaluated 42 patients with chronic frontal lesions and 38 control subjects on a modified Stroop test that allowed measurement of reaction times and errors. Planned, stratified analyses permitted identification of discrete frontal lesions that are critical for impaired performance. RESULTS: Lesions of the left ventrolateral region produced an increased number of incorrect responses to distractors. Lesions of a large portion of the right superior medial region, including anterior cingulate, supplementary motor area (SMA), pre-SMA, and dorsolateral areas, caused a slow reaction time and a decreased number of correct responses to targets. CONCLUSION: Lesions in two distinct frontal regions impair cognitive control for a Stroop task, and the mechanisms of impairment are specific to the region of injury. This is support for a general proposal that the supervisory system is constructed of distinct subsystems.
BACKGROUND:Lesions of the frontal lobes may impair the capacity of patients to control otherwise intact cognitive operations in the face of ambiguous sensory input or conflicting possible responses. OBJECTIVE: To address the question of whether focal lesions in different regions of the frontal lobes produced specific impairments in cognitive control. METHODS: We evaluated 42 patients with chronic frontal lesions and 38 control subjects on a modified Stroop test that allowed measurement of reaction times and errors. Planned, stratified analyses permitted identification of discrete frontal lesions that are critical for impaired performance. RESULTS: Lesions of the left ventrolateral region produced an increased number of incorrect responses to distractors. Lesions of a large portion of the right superior medial region, including anterior cingulate, supplementary motor area (SMA), pre-SMA, and dorsolateral areas, caused a slow reaction time and a decreased number of correct responses to targets. CONCLUSION: Lesions in two distinct frontal regions impair cognitive control for a Stroop task, and the mechanisms of impairment are specific to the region of injury. This is support for a general proposal that the supervisory system is constructed of distinct subsystems.
Authors: R I Aviv; P L Francis; R Tenenbein; P O'Connor; L Zhang; A Eilaghi; L Lee; T J Carroll; J Mouannes-Srour; A Feinstein Journal: AJNR Am J Neuroradiol Date: 2012-04-26 Impact factor: 3.825
Authors: Katherine L Possin; Simona M Brambati; Howard J Rosen; Julene K Johnson; Judy Pa; Michael W Weiner; Bruce L Miller; Joel H Kramer Journal: J Int Neuropsychol Soc Date: 2009-05 Impact factor: 2.892
Authors: Claudia Metzler-Baddeley; Derek K Jones; Jessica Steventon; Laura Westacott; John P Aggleton; Michael J O'Sullivan Journal: J Neurosci Date: 2012-12-05 Impact factor: 6.167