Related Experiment Video
Updated: May 21, 2026
14:27
Identification of Disease-related Spatial Covariance Patterns using Neuroimaging Data
Published on: June 26, 2013
Visuospatial deficits in posterior cortical atrophy: structural and functional correlates
Katia Andrade1, Aurélie Kas, Romain Valabrègue
1INSERM UMR_S 975, Centrede Recherche de l’Institut du Cerveau et de la Moelle épinière(CRICM), Paris, France.
Journal of Neurology, Neurosurgery, and Psychiatry
|May 31, 2012
Summary
In posterior cortical atrophy (PCA), spatial neglect bias is linked to right hemisphere fronto-parietal network dysfunction. This involves both brain atrophy and reduced blood flow, impacting spatial orienting.
Area of Science:
- Neuroscience
- Neurology
- Neuroimaging
Background:
- Spatial neglect, characterized by biased line bisection towards brain lesions, is observed in posterior cortical atrophy (PCA).
- The neural underpinnings of this spatial bias in neurodegenerative conditions like PCA are not well understood.
Purpose of the Study:
- To investigate the neural substrates of biased spatial orienting in PCA.
- To utilize combined structural and functional neuroimaging for this investigation.
Main Methods:
- 15 PCA patients performed a line bisection task.
- Brain Magnetic Resonance Imaging (MRI) and single-photon emission computed tomography (SPECT) were used.
- Voxel-based morphometry (VBM) assessed grey matter density, and SPECT measured regional cerebral blood flow.
Main Results:
- 47% of patients exhibited pathological spatial bias, predominantly rightward (left-sided neglect).
- Rightward deviations correlated with atrophy and hypoperfusion in the right fronto-parietal network, including parieto-temporal and frontal regions.
- Leftward deviations showed no significant correlations.
Conclusions:
- Rightward spatial bias in PCA is associated with a large fronto-parietal network dysfunction in the right hemisphere.
- This dysfunction is linked to both cortical atrophy and reduced cerebral perfusion.
- The findings highlight the neural basis of spatial neglect in PCA.
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