Anosognosia for hemiplegia (AHP) is a complex syndrome whose neural correlates are still under investigation. One hypothesis, mainly based on lesion mapping studies, is that AHP reflects a breakdown of neural systems of the right hemisphere involved in motor function. However, more recent theories have suggested that AHP may represent a disorder of cognitive systems involved in belief updating, self-referential or body processing. Two recent studies, using a method to estimate the degree of white matter disconnection from lesions, have indeed shown that patients with AHP suffer from damage of several long-range white matter pathways in association cortex. Here, we use a similar indirect disconnection approach to study a group of patients with motor deficits without anosognosia (hemiparesis or hemiplegia, HP, n = 35), or motor deficits with AHP (n = 28). The HP lesions came from a database of stroke patients, while cases of AHP were selected from the published literature. Lesions were traced into an atlas from illustrations of the publications using a standard method. There was no region in the brain that was more damaged in AHP than HP. In terms of structural connectivity, AHP patients had a similar pattern of disconnection of motor pathways to HP patients. However, AHP patients also showed significant disconnection of the right temporoparietal junction, right insula, right lateral and medial prefrontal cortex. These associative cortical regions were connected through several white matter tracts, including superior longitudinal fasciculus III, arcuate, fronto-insular, frontal inferior longitudinal, and frontal aslant. These tracts connected regions of different cognitive networks: default, ventral attention, and cingulo-opercular. These results were not controlled for clinical variables as concomitant symptoms and other disorders of body representation were not always available for co-variate analysis. In conclusion, we confirm recent studies of disconnection demonstrating that AHP is not limited to dysfunction of motor systems, but involves a much wider set of large-scale cortical networks.

Neurological deficits following stroke are traditionally described as syndromes related to damage of a specific area or vascular territory. Recent studies indicate that, at the population level, post-stroke neurological impairments cluster in three sets of correlated deficits across different behavioral domains. To examine the reproducibility and specificity of this structure, we prospectively studied first-time stroke patients (n = 237) using a bedside, clinically applicable, neuropsychological assessment and compared the behavioral and anatomical results with those obtained from a different prospective cohort studied with an extensive neuropsychological battery. The behavioral assessment at one-week post stroke included the Oxford Cognitive Screen (OCS) and the National Institutes of Health Stroke Scale (NIHSS). A principal component analysis was used to reduce variables and describe behavioral variance across patients. Lesions were manually segmented on structural scans. The relationship between anatomy and behavior was analyzed using multivariate regression models. Three principal components (PC) explained ≈50% of the behavioral variance across subjects. PC1 loaded on language, calculation, praxis, right side neglect, and memory deficits; PC2 loaded on left motor, visual, and spatial neglect deficits; PC3 loaded on right motor deficits. These components matched those obtained with a more extensive battery. The underlying lesion anatomy was also similar. Neurological deficits following stroke are correlated in a low dimensional structure of impairment, related neither to the damage of a specific area or vascular territory. Rather they reflect widespread network impairment caused by focal lesions. These factors showed consistency across different populations, neurobehavioral batteries and, most importantly, can be described using a combination of clinically applicable batteries (NIHSS and OCS). They represent robust behavioral biomarkers for future stroke population studies.

We conducted a multisite, randomized, double-blinded, controlled trial to examine the effectiveness of a digital health intervention targeting the intrinsic regulation of goal-directed alertness in patients with chronic hemispatial neglect. Methods: Forty-nine participants with hemispatial neglect, who demonstrated significant spatially biased attention after acquired brain injury, were randomly assigned to the experimental attention remediation treatment or the active control group. The participants engaged with the remotely administered interventions for 12 weeks. The primary outcome was spatial bias on the Posner cueing task (response time difference: left minus right target trials). Secondary outcomes included functional abilities (measured via the Catherine Bergego scale and Barthel index), spatial cognition, executive function, quality of life, and sleep. Assessments were conducted before and immediately after participation in the experimental intervention or control condition, and again after a 3-month no-contact period. Results: Compared with the active control group, the intervention group exhibited a significant improvement in the primary outcome, a reduction in spatially biased attention on the Posner cueing task (p = 0.010, Cohen's d = 0.96), in addition to significant improvements in functional abilities as measured on the Catherine Bergego and Barthel indices (p = 0.027, Cohen's d = 0.24). Interpretation: Our results demonstrate that our attention training program was effective in improving the debilitating attention deficits common to hemispatial neglect. This benefit generalized to improvements in real-world functional abilities. This safe, highly scalable, and self-administered treatment for hemispatial neglect might serve as a useful addition to the existing standard of care.

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Introduction: We describe a systemic neoplastic cryoglobulinemic vasculitis presenting as a large vessel occlusion (LVO) syndrome. We focus on a rare presentation of a rare condition. Case Report: A 68-year-old man was admitted to the Stroke Unit of Padova with a right middle cerebral artery syndrome. A cerebrovascular event was suspected and protocol for revascularization treatment was performed. Neuroimaging provided no evidence for infarcted tissue or medium-large vascular occlusion but hypothesized a vasculitic involvement of the small vessels of the right hemisphere. Further diagnostics demonstrated a microangiopathic involvement of the heart, kidneys, and lungs. Blood tests showed circulating cryoglobulins and further hematological investigation identified a chronic lymphatic leukemia-like lymphoproliferative disorder. High-dose steroid therapy improved the patient’s clinical status and no neurological symptoms remained at discharge. Conclusion: We discuss the clinical-radiologic presentation of a small vessel vasculitis that mimics an LVO stroke. This case focuses on the relevance of concomitant multiorgan manifestations in the hyper-acute evaluation of LVO stroke, suggesting the clinical neurologist should consider alternative etiologies as these could provide important clinical implications.