‘The anatomy underlying acute versus chronic spatial neglect’ also depends on clinical tests

Sir, We would like to make a few comments on the interesting paper recently published in Brain by Karnath et al. (2011). We were impressed by the careful assessment of spatial neglect during acute and chronic phase, which was combined with a solid voxel-wise lesion symptom mapping technique in a series of 54 patients with right-hemisphere stroke. Anatomical data indicated that lesions in the superior and middle temporal gyri, the basal ganglia, as well as the inferior occipitofrontal fasciculus are responsible for spatial neglect in both acute and chronic phases. We also had the opportunity to evaluate 69 patients with right brain lesions longitudinally. Our patients were admitted after a first right-hemisphere stroke (mean delay: 7.5 ± 14.6 days), at a mean age of 64.95 ± 14.6 years. Mean delay between the acute and chronic phase was 350.21 ± 184.7 days. These demographic data are comparable with the patients of Karnath et al . (2011). Neglect was considered as present when patients failed at least two out of eight tests (Table 1)—unlike diagnoses based on two out three tests in Karnath et al . (2011). In the acute phase, 31 patients had neglect (45%). In the chronic phase, 17 of these 31 neglect patients still showed a significant impairment (55%). Using the same voxel-wise lesion mapping as Karnath et al . (2011), we found partly different results, particularly in the acute phase (detailed below). However, we believe that major differences in the findings may depend on the clinical measures used to define neglect, since this syndrome may include heterogeneous symptoms. View this table: Table 1 Neuropsychological results on paper and pencil tests. All scores were calculated as described in Verdon et al . (2010) Bowen et al . (1999) reported that the frequency of occurrence of neglect in patients with right brain damage may vary considerably and …