Abstract
Background and aims
Neglect alexia (NA) is part of spatial neglect (SN) syndrome. Allocentric NA affects letters on the left or right side of words relative to the patient’s point of view. We aimed at describing it and its association with visual neglect.
Methods
We perform in routine care SN assessment in patients with acute phase stroke, using the Apples cancelation test (ACT) and words/pseudowords reading test. We report the results for patients who had no prior history of stroke or cognitive impairment.
Results
We included 120 patients. The mean initial NIHSS score was 3.9 ± 4.2. Right-sided strokes occurred in 49 % (59/120) of patients, bilateral strokes in 10 % (12/120). Strokes were supratentorial in 76 % (91/120) and involved both supra- and infratentorial regions in 8 % (n = 9).
Forty-five percent (54/120) of patients exhibited either allocentric or egocentric visual neglect on the ACT. Both subtypes co-occurred in 12 patients, of whom nine showed a consistent right- or left-sided visual-neglect lateralisation. No diagnostic cut-off exists for allocentric NA. Nevertheless, allocentric NA scores differed significantly (p = 0.011) between right- and left-supratentorial strokes. Allocentric NA scores were significantly associated with allocentric visual-neglect scores (p = 0.001), although the correlation was weak (R2 = 0.08).
Conclusions
We confirm the presence of allocentric NA after stroke. Its weak correlation with allocentric visual neglect suggests a clinical dissociation between these two manifestations of spatial neglect and implies that the underlying neuronal networks only partially overlap, as previously reported.
Conflict of interest
Brunet de Courssou: institutional funding from Novartis through the Novartis–SFN BRAINNS (Bourses de Recherche pour l’Avancement de l’Innovation en Neurosciences) research grant program. The other authors have nothing to disclose.