Behavioral deficits in left hemispatial neglect are related to a reduction of spontaneous neuronal activity in the right superior parietal lobule

Publication date: Available online 20 January 2020Source: NeuropsychologiaAuthor(s): Björn Machner, Janina von der Gablentz, Martin Göttlich, Wolfgang Heide, Christoph Helmchen, Andreas Sprenger, Thomas F. MünteAbstractFocal brain lesions may induce dysfunctions in distant brain regions leading to behavioral impairments. Based on this concept of ‘diaschisis’, spatial neglect following stroke has been related to structural damage of the right-lateralized ventral attention network (VAN) and disrupted inter-hemispheric functional connectivity (FC) in the bilateral dorsal attention network (DAN). We questioned whether neglect-related behavioral deficits may be determined by local dysfunction of a specific region within these brain networks.We investigated acute right-hemisphere stroke patients with left hemispatial neglect using resting-state functional MRI, neuropsychological tests of spatial attention and clinical assessment of neglect-related functional disability. In addition to conventional FC analyses between different cortical regions of interest (ROIs) in the DAN/VAN, we extracted the fractional amplitude of low frequency fluctuations (fALFF) from each ROI as a marker of regional spontaneous neuronal activity. Although DAN regions (as opposed to the VAN regions) were largely spared from structural brain damage, they exhibited a significant reduction of inter-hemispheric FC. However, significant fMRI-behavior correlations were revealed specifically for the fALFF of ...
Source: Neuropsychologia - Category: Neurology Source Type: research