Cognitive deficits in normally intelligent patients with tuberous sclerosis

Webb, Thomson, and Osborne [1991: Arch Dis Child 66:1375-1377] reported on the pattern of cerebral lesions found in an epidemiological sample of patie nts with tuberous sclerosis (TS) and clinically judged to be of normal inte llect. Varying numbers of tubers and subependymal nodules were found, but c linically there appeared to be few associated neuropsychological impairment s. Our objectives in this study were to conduct a detailed neuropsychologic al assessment to determine whether these patients were indeed free of cogni tive deficits. We report the results of a detailed neuropsychological asses sment in this sample and a matched comparison group. Although of average in telligence, most TS individuals had a significant cognitive deficit of one sort or another, and in a number of cases the pattern of cognitive impairme nts matched that seen in other neurological disorders. Additionally, the ov erall rate of cognitive deficits was significantly greater than in the cont rols. We conclude that normally intelligent individuals with TS are prone t o specific cognitive difficulties. Further research will be required to cla rify the nature of the links between the brain abnormalities and type of ne uropsychological dysfunction. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 8 8:642-646,1999. (C) 1999 Wiley-Liss, Inc.