title: Neural correlates of visual hallucinations in dementia with Lewy bodies.
abstract: BACKGROUND
  The aim of this study was to investigate the association between visual hallucinations in dementia with Lewy bodies (DLB) and brain perfusion using single-photon emission computed tomography.
  
  
  METHODS
  We retrospectively included 66 patients with DLB, 36 of whom were having visual hallucinations (DLB-hallu) and 30 of whom were not (DLB-c). We assessed visual hallucination severity on a 3-point scale of increasing severity: illusions, simple visual hallucinations and complex visual hallucinations. We performed voxel-level comparisons between the two groups and assessed correlations between perfusion and visual hallucinations severity.
  
  
  RESULTS
  We found a significant decrease in perfusion in the left anterior cingulate cortex, the left orbitofrontal cortex and the left cuneus in the DLB-hallu group compared with the DLB-c group. We also found a significant correlation between decreased bilateral anterior cingulate cortex, left orbitofrontal cortex, right parahippocampal gyrus, right inferior temporal cortex and left cuneus perfusion with the severity of hallucinations.
  
  
  CONCLUSIONS
  Visual hallucinations seem to be associated with the impairment of anterior and posterior regions (secondary visual areas, orbitofrontal cortex and anterior cingulate cortex) involved in a top-down and bottom-up mechanism, respectively. Furthermore, involvement of the bilateral anterior cingulate cortex and right parahippocampal gyrus seems to lead to more complex hallucinations.
authors.affiliation: Neuropsychology Unit, Neurology Department, University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France ; CMRR (Memory Resource and Research Center), University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France.
authors.forename: Camille
authors.initials: C
authors.lastname: Heitz
authors.affiliation: University of Strasbourg and CNRS, ICube Laboratory UMR 7357, IMIS team and FMTS (Strasbourg Federation of Translational Medicine), 1, place de l'Hôpital, 67000 Strasbourg, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Noblet
authors.affiliation: Neuropsychology Unit, Neurology Department, University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France ; CMRR (Memory Resource and Research Center), University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France ; University of Strasbourg and CNRS, ICube Laboratory UMR 7357, IMIS team and FMTS (Strasbourg Federation of Translational Medicine), 1, place de l'Hôpital, 67000 Strasbourg, France.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Cretin
authors.affiliation: Neuropsychology Unit, Neurology Department, University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France ; CMRR (Memory Resource and Research Center), University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France ; University of Strasbourg and CNRS, ICube Laboratory UMR 7357, IMIS team and FMTS (Strasbourg Federation of Translational Medicine), 1, place de l'Hôpital, 67000 Strasbourg, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Philippi
authors.affiliation: Neuropsychology Unit, Neurology Department, University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Kremer
authors.affiliation: Neuropsychology Unit, Neurology Department, University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France ; CMRR (Memory Resource and Research Center), University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Stackfleth
authors.affiliation: University of Strasbourg and CNRS, ICube Laboratory UMR 7357, IMIS team and FMTS (Strasbourg Federation of Translational Medicine), 1, place de l'Hôpital, 67000 Strasbourg, France ; Department of Nuclear Medicine, University Hospital of Strasbourg, 1, avenue Molière, 67000 Strasbourg, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Hubele
authors.affiliation: University of Strasbourg and CNRS, ICube Laboratory UMR 7357, IMIS team and FMTS (Strasbourg Federation of Translational Medicine), 1, place de l'Hôpital, 67000 Strasbourg, France.
authors.forename: Jean Paul
authors.initials: JP
authors.lastname: Armspach
authors.affiliation: University of Strasbourg and CNRS, ICube Laboratory UMR 7357, IMIS team and FMTS (Strasbourg Federation of Translational Medicine), 1, place de l'Hôpital, 67000 Strasbourg, France ; Department of Nuclear Medicine, University Hospital of Strasbourg, 1, avenue Molière, 67000 Strasbourg, France.
authors.forename: Izzie
authors.initials: I
authors.lastname: Namer
authors.affiliation: Neuropsychology Unit, Neurology Department, University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France ; CMRR (Memory Resource and Research Center), University Hospital of Strasbourg, 1, avenue Molière, 67098 Strasbourg, France ; University of Strasbourg and CNRS, ICube Laboratory UMR 7357, IMIS team and FMTS (Strasbourg Federation of Translational Medicine), 1, place de l'Hôpital, 67000 Strasbourg, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Blanc