Neural substrates in patients with visual-spatial neglect recovering from right-hemispheric stroke

Abstract

Visual-spatial attention disorder after stroke seriously affects recovery and quality of life in stroke patients. Previous studies have shown that some patients recovery rapidly from visual-spatial neglect (VSN), but the brain networks underlying this recovery are not well understood. Using functional magnetic resonance imaging, we aimed to identify network differences between patients who rapidly recovered from VSN and those with persistent VSN. The study included 30 patients with VSN who suffered subacute stroke. Patients were examined 2–4 weeks after stroke onset and 4 weeks after the initial assessment. At the last evaluation, patients in the persistent VSN (n = 15) and rapid recovery (n = 15) groups underwent paper-and-pencil tests. We defined the bilateral frontal eye fields, bilateral intraparietal sulcus in the dorsal attention network, and right temporoparietal junction and ventral frontal cortex areas in the ventral attention network as regions of interest (ROI) and measured whole-brain ROI-based functional connectivity (FC) and amplitude of low-frequency fluctuations (ALFF) in subacute right-hemisphere stroke patients. VSN recovery was associated with changes in the activation of multiple bilateral attentional brain regions. Specifically, persistent VSN was associated with lower FC in the right superior frontal gyrus, right inferior temporal gyrus, right medial orbitofrontal cortex, left precuneus, right inferior parietal gyrus, right medial frontal gyrus, right rectus gyrus, left superior frontal gyrus, left middle cingulate gyrus, right superior temporal pole, right postcentral gyrus, and right posterior cingulate gyrus compared to that in those with rapid recovery, whereas ALFF in the left cerebellum were decreased in patients with persistent VSN. Our results demonstrate that the DAN rather than the VAN, plays a more important role in recovery from VSN, and that the cerebellum is involved in recovery. We believe that our results supplement those of previous studies on recovery from VSN.

Altered Regional Brain Spontaneous Activity and Functional Connectivity in Patients of Non-Acute Subcortical Stroke With versus Without Cognitive Impairment: A Resting-State fMRI Study.

“…However, few studies focused on the FC of REC in stroke patients. The mPFC may also be involved in visuospatial attention function, including the REC, as evidenced by the manifestation of reduced FC of several mPFC subdistricts with the dorsal attention network nodes and the association with symptom regression [45], which is consistent with our study.…”

Spontaneous unilateral spatial neglect recovery after brain tumour resection: A multimodal diffusion and rs‐fMRI case report

“…Moreover, our study (i) highlights the crucial role of the right SLF‐III in this syndrome, whose damage is sufficient for the manifestation of USN, (ii) reinforces the view of USN as a syndrome derived from a disconnection of WM fibres (Thiebaut de Schotten et al, 2014), considering that USN was observed with subcortical impairment of WM fibres but without cortical damage (i.e. before surgery) and (iii) strengthen the notion that a (dis)functional activation of the DAN and its functional restoring after surgery is crucial respectively for the emergence and the recovery of USN (Cao et al, 2022; Corbetta et al, 2005).…”

Parameters of Auditory Evoked Related Potentials P300 in Disorders of Different Cognitive Function Domains (Visuospatial/Executive and Memory) in Elderly Hypertensive Persons

“…Recovery of reduced visual-spatial attention function after vascular cerebral disturbances in the right hemisphere in the early recovery period (4 weeks after the event) was associated with bilateral activation of cerebral areas. However, the persistence of reduced visual-spatial attention function after suffering cerebral ischemia was found pre-dominantly in the right cortical areas-superior and medial frontal, inferior temporal, medial orbitofrontal, inferior parietal gyrus, right inferior temporal gyrus, right medial orbitofrontal cortex and superior temporal pole in the right hemisphere [25].…”

“…Visual-spatial attention disorder, visual sensory (input) neglect, may be a cause of difficulties in performing MoCA tests on certain tasks (drawing clocks, geometric shapes, including with a sequence of letters and numbers). The syndrome of visuospatial neglect is one of the phenomena of optic-spatial agnosia, which occurs when there is unilateral damage to the cortical structures of the posterior brain regions and when visual function is preserved, but the neural networks underlying this recovery are not well understood [24,25]. Further, temporarily occurring and transient visual neglect may be part of a cognitive-affective syndrome following cerebellar circulatory disturbances, which is very difficult to suspect either clinically or by paper-based testing [26].…”