The impact of lesion laterality on neuropsychological change following posterior pallidotomy: A review of current findings This paper reviews 7 studies evaluating the impact of lesion laterality on the neuropsychological sequelae of posterior pallidotomy for treatment of Parkinson's disease. Left lesions of the internal globus palllidus (GPi ) were associated with subtle deficits on measures sensitive to frontal lobe function. The findings of a randomized clinical trial including a patient control group indicated that many of these deficits were transient, resolving by 6 months following surgery. Right GPi lesions were not consistently associated with neuropsychological deficit, except in one study that included a significant proportion of demented patients. It is hypothesized that when neuropsychological decline is present following surgery, this reflects impingement of posterior GPi lesions into proximal regions such as anterior GPi or the external pallidum that participate in cognitive basal ganglia-thalamocortical circuits. The findings from neuroimaging will be important for elucidating the relationship between lesion locus and neuropsychological sequelae. Copyright 2000 Academic Press. Brain Cogn 2000 Apr;42(3):379-98 Green J, Barnhart H Department of Neurology and Wesley Woods Geriatric Center, Emory University School of Medicine. PMID: 10753486, UI: 20218808 janet paterson 53 now / 41 dx / 37 onset 613 256 8340 / PO Box 171 Almonte Ontario K0A 1A0 Canada visit my website "a new voice" at: http://www.geocities.com/janet313/