Le 15/10/2021 de 13:30 à 15:30
La négligence spatiale englobe la perturbation du sens de verticalité après AVC
Rémi Lafitte (Saint Martin d'Hères, France), Marie Jeager (Grenoble, France), Céline Piscicelli (Grenoble, France), Eve Dupierrix (Saint Martin d'Hères, France), Dai Shenhao (Grenoble, France), Anne Chrispin (Grenoble, France), Patrice Davoine (Grenoble, France), Dominic Pérennou (Grenoble, France)
Objective : There is mounting evidence that, after stroke, impaired internal model of verticality is strongly related to spatial neglect. It raises questions as to which modalities of spatial neglect and verticality perception are related to each other? We assume that this link stems from a strong relationship between body neglect (BN) and an impaired postural vertical (PV), both referring to the body. To test this hypothesis, we analysed the relationships between BN, non-body neglect (NBN), PV, and visual vertical (VV), in a series of individuals with right hemisphere stroke (RHS).
Material / Patients and Methods : We investigated a series of 77 individuals with RHS, with complete assessments of BN and NBN (four tests each), VV and PV, performed at the same time between one and three months post-stroke. Abnormality was diagnosed from two pathological tests both for spatial neglect and verticality perception. Composite scores were computed for BN and NBN.
Results : All individuals (Median age=67) with verticality perception impairment (n=26) had spatial neglect (n=52), but the reverse was not true. Whatever the modality, spatial neglect and verticality biases were moderately correlated (r ranging from -.64 to -.41; all p<.001). A principal component analysis revealed that data variance was mainly explained by one component, comprising all factors with the following loadings: BN=.88, NBN=.84, PV=-.80, VV=-.73.
Discussion - Conclusion : Our results reveal that spatial neglect encompasses impaired transmodal verticality perception, suggesting that biased verticality perception is a form of graviceptive neglect. BN, NBN, PV, and VV belong to the same dimension. The attentional component of spatial neglect likely explains their moderate correlations.
Keywords : Body neglect; non-body neglect; postural vertical; visual vertical