QUANTITATIVE EEG IN SUBCORTICAL NEGLECT

Right-sided capsulo-lenticular strokes may cause left visuo-spatial ne glect. The neural mechanism most frequently evoked to account for the occurrence of related cognitive disorders is remote cortical dysfuncti on in the posterior part of the right hemisphere. We studied 33 patien ts with capsulo-lenticular stroke, with (n = 16) or without (n = 17) a ssociated subcortical neglect. A 20-channel EEG cartography system was used. Four regions of interest were delineated on the topographic map . Absolute delta and theta amplitude peaks were obtained, as well as l eft-to-right ratios between activities in homologous regions of intere st. The population was subdivided into two groups according to the pre sence or absence of neglect. Delta activity was higher in neglect pati ents than in patients without neglect, but the magnitude of delta acti vity differences between the two groups of patients did not depend on the site. The left-to-right ratio of delta activity between posterior homologous regions was lower in neglect patients, suggesting that righ t posterior dysfunction producing an imbalance between these regions m ight contribute to the emergence of the attention disorder. (C) 1998 E lsevier, Paris.