White matter lesions impair initiation of FAS flow

Word fluency performance is known to rely on left frontal cortical regions and has also been shown to be affected by lesions in the white matter, whic h may be seen as white matter hyperintensities (WMH) on magnetic resonance imaging. However, word fluency may be divided into two independent componen ts, initial and late performance, separated in time [J Clin Exp Neuropsycho l 1998;20:137-143], The purpose of the current study was to investigate the relationship between the two components of FAS fluency performance and WMH , Patients varying in degree of memory impairment participated: Alzheimer's disease, mild cognitive impairment and subjective memory disorder. WMH wer e rated with the Scheltens scale in the periventricular and deep subcortica l areas, Results demonstrated that WMH in this sam pie of patients may be s ummarized in two indices according to a principal factor analysis, one ante rior factor mainly related to WMH in the frontal lobes and adjacent to vent ricles, and a second posterior factor related to parietal and occipital WMH . The initial FAS performance was related to anterior WMH, in particular le ft frontal or lateral periventricular hyperintensities, whereas the late FA S performance was not related to any index of WMH, Copyright (C) 2001 S. Ka rger AG, Basel.