Introduction: Hemispatial neglect is a disabling consequence of right hemisphere stroke. Evidence suggests that viewer-centered neglect (VCN, in which the patient neglects the left side of the viewer) and stimulus-centered neglect (SCN, in which the patient neglect the left side of each stimulus, irrespective of the location with respect to the viewer) are distinct syndromes driven by damage to different brain areas. However, lesions associated with having both VCN and SCN are unknown.
Methods: We tested 158 participants (mean age = 60.7 years, 47.5% female, 10.7% left handers) with a first-time, right hemisphere ischemic stroke on a neglect battery within 48 hours of stroke. We dichotomously defined VCN, SCN, and both types of neglect. We traced the total area of ischemia (infarcted on DWI or significantly hypoperfused on PWI), normalized to the JHU atlas. We identified associations between neglect and total dysfunctional tissue (abnormal on DWI and/or PWI) in each parcel on the atlas using SVM, regressing for age and correcting for multiple comparisons.
Results: A total of 33 (20.9%) of patients with acute right hemisphere stroke had neglect; 25 had VCN only, 5 had SCN only, and 3 had both. Multivariable logistic regression with age, handedness, sex, and lesion volume as independent variables and any significant VCN (VCN or both) as the dependent variable, showed that these variables accounted for 27% of the variance in any significant VCN (r2=0.27, p<0.00001), but only age (OR:1.06, 95% CI: 1.02-1.13, p= 0.001) and lesion volume were significantly associated with VCN independently of other variables. The same variables did not account for any significant SCN (SCN only or both). VCN is associated with right posterior fronto-parietal cortex (dorsal) dysfunction. In addition, SCN is associated with more ventral right posterior temporoparietal infarct/hypoperfusion. Having both types of neglect is associated with frontal lesions and white matter tracts.
Conclusion: Results confirm that VCN and SCN usually dissociate, but can co-occur with right frontal lesions extending to deep white matter.
Conflicts of interest: None