title: A neuroanatomical model of space-based and object-centered processing in spatial neglect.
abstract: Visual attention can be deployed in space-based or object-centered reference frames. Right-hemisphere damage may lead to distinct deficits of space- or object-based processing, and such dissociations are thought to underlie the heterogeneous nature of spatial neglect. Previous studies have suggested that object-centered processing deficits (such as in copying, reading or line bisection) result from damage to retro-rolandic regions while impaired spatial exploration reflects damage to more anterior regions. However, this evidence is based on small samples and heterogeneous tasks. Here, we tested a theoretical model of neglect that takes in account the space- and object-based processing and relates them to neuroanatomical predictors. One hundred and one right-hemisphere-damaged patients were examined with classic neuropsychological tests and structural brain imaging. Relations between neglect measures and damage to the temporal-parietal junction, intraparietal cortex, insula and middle frontal gyrus were examined with two structural equation models by assuming that object-centered processing (involved in line bisection and single-word reading) and space-based processing (involved in cancelation tasks) either represented a unique latent variable or two distinct variables. Of these two models the latter had better explanatory power. Damage to the intraparietal sulcus was a significant predictor of object-centered, but not space-based processing, while damage to the temporal-parietal junction predicted space-based, but not object-centered processing. Space-based processing and object-centered processing were strongly intercorrelated, indicating that they rely on similar, albeit partly dissociated processes. These findings indicate that object-centered and space-based deficits in neglect are partly independent and result from superior parietal and inferior parietal damage, respectively.
authors.affiliation: Laboratory of Cognitive Neurorehabilitation, Faculty of Medicine, University of Geneva, Geneva, Switzerland. ele.pedrazzini@gmail.com.|Division of Neurorehabilitation, Department of Clinical Neurosciences, Geneva University Hospital, 26, Av. de Beau-Séjour, 1211, Geneva 14, Switzerland. ele.pedrazzini@gmail.com.
authors.forename: Elena
authors.identifier: http://orcid.org/0000-0001-8222-2114
authors.initials: E
authors.lastname: Pedrazzini
authors.affiliation: Laboratory of Cognitive Neurorehabilitation, Faculty of Medicine, University of Geneva, Geneva, Switzerland.|Division of Neurorehabilitation, Department of Clinical Neurosciences, Geneva University Hospital, 26, Av. de Beau-Séjour, 1211, Geneva 14, Switzerland.
authors.forename: Armin
authors.initials: A
authors.lastname: Schnider
authors.affiliation: Laboratory of Cognitive Neurorehabilitation, Faculty of Medicine, University of Geneva, Geneva, Switzerland. radek.ptak@hcuge.ch.|Division of Neurorehabilitation, Department of Clinical Neurosciences, Geneva University Hospital, 26, Av. de Beau-Séjour, 1211, Geneva 14, Switzerland. radek.ptak@hcuge.ch.|Faculty of Psychology and Educational Sciences, University of Geneva, Geneva, Switzerland. radek.ptak@hcuge.ch.
authors.forename: Radek
authors.initials: R
authors.lastname: Ptak
mesh_terms: D000368:Aged; D001288:Attention; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual; D010468:Perceptual Disorders / Q000000981:diagnostic imaging / Q000473:pathology*; D013028:Space Perception; D065855:Spatial Processing
keywords: Attention network; Frontal lobe; Parietal lobe; Spatial neglect; Visual attention