Personal Neglect Following Unilateral Right And Left Brain Damage

Abstract

Patients showing unilateral neglect fail to respond, report or orient to stimuli located in the contralesional (usually the left) side of the environment, of own body or of mental representations. Several studies have investigated different forms of neglect for stimuli located in the extra personal or reaching space confirming that this syndrome is more frequent and persistent following right than left brain damage. However, relatively little attention has been paid to the personal domain of this syndrome and the cognitive mechanisms underlying personal neglect (PN) are not well known. PN was assessed on a sample of 101 right- and 96 left-brain damaged (RBD and LBD, respectively) patients by means of two classical tests: the Comb & Razor Test and the Fluff Test. Patients were asked to perform the Fluff Test also with their eyes opened. PN was more frequent amongst RBD (42.57%) than LBD patients (35.41%); however, the difference was not significant. Considering RBD patients, each test identified a different percentage of PN (Comb and Razor=26.73%; Fluff test with eyes closed=35.64%; Fluff Test with eyes opened=22.77%). The difference between the two versions of the Fluff test was significant. On the other hand, in the LBD group, all the three tests assessed similar percentages of PN (i.e. Comb and Razor test=21.88%; Fluff Test with eyes closed=20.83%; Fluff Test with eye opened=20.83%) with no significant differences. Our findings suggest that PN following lesions of the left hemisphere may be more frequent than previously reported, and that PN following right hemisphere damage may be linked to impairment of different underlining mechanisms