Table A2.
Summary of functional neuroimaging studies of hallucinating patients with LBD. Only main results related to VH are reported.
| Study | Sample | Age 1 | Disease Duration (years) 1 | VH | MMSE 1 | H&Y | Neuroimaging Methods—VH | Main Results: Neuroimaging and VH |
|---|---|---|---|---|---|---|---|---|
| Boecker et al. (2007) [61] | 8 PD VH | 72.88 (6.60) 2 | 11.00 (6.46) 2 | NPI | 25.75 (1.67) 2 | 3.31 (0.59) 3 | FDG-PET Whole brain; covariate: UPDRS III; group comparison |
Cerebral glucose metabolism p < 0.05 corrected VH < NVH: bilat. IPL, precuneus, L SG, MFG, MTG, parahippocampal gyrus, LG, R cingulate gyrus |
| 13 PD NVH | 70.56 (6.96) | 8.05 (5.85) | 26.82 (1.54) | 2.68 (1.54) | ||||
| Erskine et al. (2015) [47] | 17 DLB | 81.5 (5.5) | NA | NPI | 19.0 (5.1) | NA | Task-based fMRI fMRI protocol: see Taylor et al. (2012) [23]; ROI: LGN; correlation analysis with NPIhall |
fMRI activations Correlations between NPIhall and BOLD activation in the LGN: NS |
| 15 AD | 82.5 (9.2) | 20.8 (4.4) | ||||||
| 19 HC | 77.6 (7.1) | 29.0 (1.2) | ||||||
| Firbank et al. (2016) [67] | 30 DLB | 76.4 (6.0) | 39.3 (27.9) 7 | NPI | 21.7 (4.2) | NA | FDG-PET Covariates: CAMCOG, UPDRS-III, disease duration; voxel-wise correlation with NPIhall |
Cerebral glucose metabolism p < 0.05 cluster-level corrected VH sev. and freq. associated with occipital hypometabolism |
| Franciotti et al. (2015) [16] | 15 sPD VH | 70 (6) 2 | 11.3 (4.3) 4,5 | NPI and semi-structured interview | 24.3 (2.2) 2 | 3.0 (0.5) 5 | Resting-state fMRI ICA (30 components), 9 ROIs centred on the DMN clusters; nuisance factor: age; fALFF of each ROI; group comparisons Cortical thickness 6 |
Functional connectivity of ROIs centred on the DMN sPD VH > sPD NVH: L SFS – L IPL; LSFS – L IPL; LSFS – R IPL; L SFS – PCC; R SFS – L IPL; R SFS; R IPL; R SFS – PCC; L LPC – R LPC; L IPL – R IPL; L IPL – PCC; R IPL – PCC sPD VH > ePD NVH L SFS and L IPL fALFF sPD VH > sPD: R SFS, MFG, LPC, IPL; L MFG, IPL |
| 15 sPD NVH | 68 (11) | 12.0 (4.5) 5 | 24.7 (1.8) | 3.0 (0.6) 5 | ||||
| 15 ePD NVH | 66 (9) | 3.3 (1.8) | 26.2 (1.8) | 2.1 (0.4) | ||||
| 15 MSA | 67 (5) | 3.9 (1.8) | 25.2 (1.7) | 3.2 (0.8) | ||||
| 15 HC | 69 (6) | - | 28.7 (0.7) | - | ||||
| Gasca-Salas et al. (2016) [62] | 9 PD VH | 70.7 (3.9) 2 | 14.7 (5.4) 2 | UPDRS I | 27 (1.7) 2 | NS differences | FDG-PET Whole brain; covariates: age, ed., group comparison |
Cerebral glucose metabolism p < 0.05 corrected VH < NVH: R LG, ITG, precuneus, precentral gyrus, L postcentral gyrus, bilat. MOG |
| 12 PD NVH | 70.8 (3.4) | 14.3 (6.3) | 25.9 (2.7) | |||||
| 19 HC | 70.1 (3.1) | - | 29.1 (1.2) | |||||
| Goetz et al. (2014) [54] | 1 PD VH | 66 | 4 | African tribesmen, chimpanzees, people in civil war uniform, catholic nuns | Intact cognitive function | NA | fMRI during VH VH during scan: African tribesmen and chimpanzees; event-related design; comparison between hallucination and non-hallucination |
p < 0.001 uncorrected Increased activations during VH: bilat. ACC, PCC, insula, R medial frontal gyrus, postcentral gyrus, thalamus, brainstem Decreased activations during VH: R LG, FG, IOG, cingulate, L MFG, R STG |
| Heitz et al. (2015) [73] | 36 DLB VH | 71.7 (10.2) 2 | NA | Assessed by expert neurologists | 21.7 (5.6) 2 | NA | SPECT [99mTc]ECD; covariates: age, type of tracer; voxel-based comparison; association between cerebral perfusion and sev. of VH |
Cerebral perfusion p < 0.001 uncorrected VH < NVH: L ACC, orbitofrontal cortex, cuneus Association with VH sev.: bilat. ACC, R parahippocampal gyrus, L orbitofrontal cortex, L cuneus |
| 30 DLB NVH | 73.5 (6.9) | 23.3 (4.3) | ||||||
| Holroyd and Wooten (2006) [48] | 3 PD VH | 69.7 (8.7) 2 | NA | Based on definition of VH | 31.7 (2.1) 2,8 | NA | Task-based fMRI Visual task: coloured geometric shapes moving in random directions; baseline: stationary crosshair; group comparison |
fMRI activations VH > NVH: bilat. cuneus, LG, FG, and MTG VH < NVH: primary visual cortex |
| 3 PD NVH | 66.0 (2.7) | 34.3 (2.1) 8 | ||||||
| Howard et al. (1997) [55] | 1 DLB VH | 74 | 18 7 | Markets, factories, busy roads, docks; no insight | 16 | NA | fMRI during VH VH during scan: pigeons, sparrows, pheasants; exposure to photic stimulation; comparison between hallucination, and hallucination-free state |
Hallucination-free activations: V1 and V2 bilaterally Activations during VH: limited activation in V1 and V2 |
| Iizuka and Kameyama (2016) [18] | 24 DLB | 73 (68, 79) 11 | 2.8 (1.8, 3.2) 11 | NPI | 23 (20.5, 24) 11 | NA | FDG-PET Voxel-wise; ROI: CIS ratio; SUVR in PCC and precuneus + cuneus; correlations with NPIhall Structural MRI 6 |
Positive correlation with NPIhall in DLB: CIS ratio Negative correlation with NPIhall in DLB: SUVR in precuneus/cuneus |
| 24 AD | 74 (69, 81) 11 | 2.3 (1.6, 2.6) 11 | 23 (21, 24.5) 11 | |||||
| Imamura et al. (1999) [65] | 16 DLB VH | 72.5 (4.6) 2 | 23.1 (13.0) 2,7 | NPI | 19.5 (3.9) | NA | FDG-PET 66 ROIs; covariate: MMSE |
Cerebral metabolic rate of glucose VH > NVH: R posterior temporal and parietal areas |
| 6 DLB NVH | 72.8 (5.3) | 28.0 (14.4) 7 | 15.0 (3.0) | |||||
| 16 AD | 73.2 (4.6) | 22.2 (13.8) 7 | 19.7 (3.5) | |||||
| Kantarci et al. (2012) [19] | 21 DLB | 73 (60, 87) 9 | NA | Freq. of VH: four-point scale 90% of DLB with VH |
22 (6, 29) 9 | NA | FDG-PET Association between FDG uptake and freq. of VH Structural MRI 6 |
Cerebral glucose metabolism Negative association with VH freq.: occipital FDG uptake |
| 21 AD | 77 (58, 92) 9 | 21 (6, 28) 9 | ||||||
| 42 HC | 74 (59, 87) 9 | 29 (27, 30) 9 | ||||||
| Kataoka et al. (2008) [78] | 1 PDD VH | 72 | NA | Well-formed objects, humans, animals; VH developed four years after the onset of parkinsonians symptoms | 27 10 | NA | SPECT during VH [99mTc]ECD; VH during scan: spider without delusions |
Increased regional cerebral blood flow: L STG, MTG, IFG, and apex of R temporal lobe |
| Lefebvre et al. (2016) [49] | 18 PD VH | 63.50 (5.94) 2 | 9.06 (4.11) 2 | NPI Minor VH |
28.00 (1.24) 2 | 2 (2, 2) 2,11 | Task-based fMRI Visual detection task (threshold evaluation): circular gratings; whole brain analysis; covariates: HDRS, TMT-B/TMT-A, Stroop error score |
Behavioural results Visual detection threshold: NS fMRI activations at visual threshold p < 0.01 cluster-level corrected VH > NVH: R cerebellum, occipital cortex, PFC VH < NVH: L cingulate, temporal, occipital cortices, caudate nucleus |
| 16 PD NVH | 62.69 (4.09) | 8.00 (5.74) | 28.88 (1.20) | 2 (2, 2) 2,11 | ||||
| 17 HC | 62.76 (4.19) | - | 28.47 (1.70) | - | ||||
| Lobotesis et al. (2001) [74] | 23 DLB | 79.4 (9) | 60.7 (32) 7 | Detailed psychiatric history 18 DLB VH |
16.0 (6.1) | NA | SPECT 99mTc-HMPAO; ROI: occipital hypoperfusion; group comparison |
Regional cerebral blood flow VH vs. NVH: NS |
| 50 AD | 81.6 (7) | 83.1 (34) | 17.3 (5.5) | |||||
| 20 HC | 78.1 (5) | - | 28.4 (1.5) | |||||
| Matsui et al. (2006) [70] | 31 PD VH | 71.1 (8.0) 2 | 10.9 (5.1) 3 | Clinical evaluation and information from patients and caregivers | 25.7 (3.2) 2 | 3.2 (0.4) 2 | SPECT [123I]IMP; group comparison; multivariate logistic regression analysis with disease duration and levodopa equivalent dose as explanatory variables |
Brain perfusion VH < NVH: bilat. IPL, ITG, precuneus gyrus, occipital cortex Significant after correcting for disease duration and levodopa equivalent dose: bilat. precuneus, L IPL, R occipital cortex |
| 39 PD NVH | 69.0 (7.7) | 6.7 (5.7) | 26.4 (2.8) | 3.0 (0.6) | ||||
| Meppelink et al. (2009) [51] | 9 PD VH | 61.2 (8.2) 2 | 8.1 (5.0) 2 | NPI and questionnaire based on VH characteristics in PD | 26.8 (1) 2 | NA | Task-based fMRI Perceptual recognition task: animals, well-known objects, and meaningless objects gradually popping out; covariates: movement parameters |
Behavioural results VH vs. NVH (both PD groups were slower than HC): NS; images recognised: VH 76%; NVH 86% fMRI activations During pop-out: NS between groups p < 0.001 cluster-level corrected Before pop-out: VH < NVH: R SFG, L LG, bilat. FG |
| 14 PD NVH | 64.6 (7.8) | 8.7 (4.7) | 27.4 (1.3) | |||||
| 13 HC | 58.5 (7.5) | - | 27.9 (0.9) | |||||
| Miyazawa et al. (2010) [69] | 22 DLB | 74.5 (6.9) | NA | Reported by patients and relatives 10/ in group A, and 4/ in group B |
NA | FDG-PET Two groups: (A) hypermetab. in peri-motor areas, cerebellum, and basal ganglia; (B) hypermetab. in none, one, or two regions; group comparison in VH freq. |
Visual hallucinations more frequent in group A | |
| Group A | 74.8 (6.44) 2 | 16.2 (6.95) 2 | ||||||
| Group B | 76.6 (6.29) | 21.0 (5.67) | ||||||
| Nagahama et al. (2010) [75] | 100 DLB | 76.7 (6.7) | NA | Semi-structured interview Factor 3: hallucination of person and feeling of presence Factor 4: hallucination of animals, insects and objects |
21.0 (3.9) | NA | DLB patients: Factor analysis, four factors of psychotic symptoms identified SPECT ROIs DLB ≠ HC; relationship between psychotic symptoms factors and regional cerebral blood flow; covariates: age, sex, MMSE, UPDRS-III, dysphoria |
Regional cerebral blood flow Areas of hypoperfusion associated to factor 3 compared to the others: bilat. angular gyrus, R SG, L ventral occipital gyrus No areas of hypoperfusion associated to factor 4 |
| 21 HC | 77.2 (4.8) | - | ||||||
| Nagano-Saito et al. (2004) [63] | 8 PD VH | 67.6 (6.2) 2 | 8.6 (5.0) 2 | NA | 28.3 (1.8) 2 | 3.6 (0.9) 2 | FDG-PET Whole brain; ROI: dorsolateral PFC, primary visual cortex, occipital association cortex, primary motor cortex; group comparison |
Relative regional cerebral metabolic rate for glucose p < 0.05 cluster-level corrected VH > NVH: L SFG ROI: dorsal PFC |
| 11 PD NVH | 66.0 (7.5) | 5.1 (3.8) | 28.5 (1.7) | 3.2 (0.5) | ||||
| 13 HC | 66.2 (4.9) | - | 29.1 (1.0) | - | ||||
| O’Brien et al. (2005) [77] | 15 DLB | 73.8 (7) | 2.8 (2.1) | NPIhall decreased over one year | 16.5 (4) | NA | SPECT 99mTc-HMPAO; changes after one year; multiple regression between change in perfusion and change in NPIhall |
Change in perfusion p < 0.05 cluster-level corrected DLB/PDD: negative association between hallucination score and perfusion in L PCC and precuneus |
| 14 PDD | 71.9 (6) | 2.9 (2.8) | 20.9 (4) | |||||
| Oishi et al. (2005) [71] | 24 PD VH | 69.5 (7.2) 2 | 11.1 (5.0) 2 | Clinical evaluation and information from patients and caregivers | 25.1 (3.7) 2 | 3.3 (0.5) 2 | SPECT [123I]IMP; voxel-by-voxel comparison; covariates: MMSE, duration of disease |
Regional cerebral blood flow p < 0.05 corrected VH < NVH: R FG |
| 41 PD NVH | 68.6 (7.3) | 9.1 (5.0) | 26.5 (3.1) | 3.0 (0.5) | ||||
| Osaki et al. (2005) [72] | 20 PD | 60.0 (11.3) | 8.4 (4.2) | Structured clinical assessment 9 PD with VH, 10 PDD with VH |
26.4 (4.1) | NA | SPECT [123I]IMP; 23 ROIs: frontal, temporal, parietal, occipital areas, pons; group comparison |
Regional cerebral blood flow VH vs. NVH: NS |
| 10 PDD | 61.0 (8.5) | 11.6 (4.1) | 17.4 (6.3) | |||||
| Park et al. (2013) [64] | 7 PD VH | 71.0 (4.7) 2 | 5.4 (3.5) 2 | NPI | 26.1 (1.7) 12 | 2 .0 (0.0) 2 | FDG-PET Whole brain; group comparison; whole brain correlation with NPIhall |
Cerebral glucose metabolism p < 0.001 uncorrected VH < NVH: bilat. middle and inferior temporal cortex, L LG, and L angular gyrus CI VH < NVH: temporo-parieto-occipital cortices Negative correlation with NPI hallucinations score: glucose metabolism in bilat. STG, L FG, L Heschl’s gyrus |
| 8 PD CI VH | 67.8 (6.8) | 6.8 (3.1) | 21.6 (5.1) | 2.2 (0.7) | ||||
| 13 NVH | 66.3 (5.0) | 5.1 (3.1) | 26.9 (1.4) | 1.5 (0.8) | ||||
| Pasquier et al. (2002) [76] | 34 DLB | 73.8 (8) | 3.3 (2.5) | NPI 26 DLB VH |
17.1 (6.7) | NA | SPECT [99mTc]ECD; ROI: R and L occipital region; group comparison |
Cerebral perfusion VH < NVH: R occipital region |
| 28 AD | 76.3 (7.3) | 3.4 (2.7) | 15.8 (6.5) | |||||
| Peraza et al. (2014) [57] | 16 DLB | 76.2 (5.7) | NA | NPI | 24.2 (3.75) | NA | Resting-state fMRI Covariates: age, sex, grey matter; regression of sev. and freq. of VH with seeded significant cluster from dual regression DLB < HC |
Association with NPIhall: L fronto-parietal, and sensory-motor networks (uncorrected) No association with temporal resting-state network |
| 17 HC | 77.3 (4.7) | 29.1 (0.83) | ||||||
| Peraza et al. (2015) [58] | 18 DLB | 77.2 (6.18) | NA | NPI | 23.6 (3.9) | NA | Resting-state fMRI Graph analysis; correlation between NPIhall and integrated networks measures |
No association between integrated network measures and NPIhall Correlation with NPIhall: node degree (L postcentral gyrus, putamen), nodal betweenness centrality (R intracalcarine cortex and FG) |
| 19 AD | 74.7 (8.5) | 22.58 (2.9) | ||||||
| 17 HC | 76.8 (5.7) | 29.1 (0.85) | ||||||
| Perneczky et al. (2008) [66] | 14 DLB VH | 69.86 (6.76) 2 | 5.85 (4.88) 2 | NPI | 19.57 (5.27) 2 | NA | FDG-PET Whole brain; covariate: MMSE, UPDRS III, group comparison |
Relative cerebral metabolic rate of glucose p < 0.001 uncorrected VH < NVH: R temporo-occipital conjunction, and MFG |
| 7 DLB NVH | 68.86 (3.02) | 5.71 (2.67) | 23.14 (2.55) | |||||
| 16 HC | 65 (8) | - | 30 (0) | |||||
| Ramirez-Ruiz et al. (2008) [52] | 10 PD VH | 73 (1.9) 2 | 11.1 (1.7) 2 | Presence of VHs at least seven times per week, NPI | 25.8 (0.6) 3,13 | 3.1 (0.4) 2 | Task-based fMRI One back repetition detection task (face recognition); group comparison |
Behavioural results VH < NVH: number of correct responses VH > NVH: false-positive recognition fMRI activations p < 0.05 cluster-level corrected VH < NVH: R IFG (controlling for antipsychotic intake) and SFG VH > NVH: R IFG |
| 10 PD NVH | 72.5 (1.9) | 11 (1.5) | 29.4 (0.4) | 2.5 (0.2) | ||||
| 10 HC | 71.6 (1.6) | - | 29.9 (0.5) | - | ||||
| Shine et al. (2015) [59] | 10 PD pBPP | 69.5 (8) 2 | 6.9 (4) 2 | MDS criteria for VH Patients with high % of misperceptions on the BPP (PD pBPP, based on a cut score) also presented VH |
26.0 (3) 2,14 | NA | Resting-state fMRI ROI: DAN, DMN, VAN, visual network; multiple regression analysis between BPP error scale, strength of mental imagery, and strength of connectivity within and between each network |
BPP error score and strength of mental imagery predicted increased connectivity within the VAN and DMN, and decreased connectivity between the DAN and VAN, and the VAN and visual network, and DAN and visual network. BPP error score predicted increased connectivity within VAN and DMN, and impaired connectivity between the VAN and DAN. Strength of mental imagery was related to degree of impaired connectivity between the VAN and visual network |
| 9 PD nBPP | 67.1 (7) | 4.4 (3) | 27.6 (2) 14 | |||||
| 10 HC | 63.5 (8) | - | 28.5 (1) 14 | |||||
| Shine et al. (2015) [53] | 21 PD pBPP | 69.3 (6) 2 | 6.0 (3) 2 | UPDRS-II, SCOPA-PC Patients with high % of misperceptions on the BPP (PD pBPP, based on a cut score) also presented VH |
27.2 (2) 2,14 | 2.2 (1) 2 | Task-based fMRI BPP paradigm during fMRI; ICA, networks of interest: DMN, DAN, VAN, VIS; activity during correct stable items; comparison in BOLD signal between misperceptions and correct stable images; functional coupling between networks; group comparisons |
Activity during correctly identified stable items: Increased activity in the VIS, VH vs. NVH: VIS, DMN, VAN: NS; decreased activity in DAN Activity during misperceptions: decreased activity in the DAN Misperceptions vs. correct stable images in VH: visual misperception increased activity in VAN, DMN Functional coupling between networks during misperceptions in VH: increase in functional coupling between DMN and VIS; decreased in functional coupling between DAN and DMN, and VAN |
| 14 PD nBPP | 66.3 (5) | 4.7 (4) | 28.6 (2) 14 | 2.1 (1) | ||||
| Stebbins et al. (2004) [50] | 12 PD VH | 71.08 (6.39) 2 | 13.92 (4.89) 2 | Self-report, NPI, SAPS | 26.17 (2.25) 2 | 3 (2–4) 2,9 | Task-based fMRI Stroboscopic task; kinematic task (apparent motion); whole brain and SVC; covariate: MMSE; group comparisons |
fMRI activations Whole brain, p < 0.001 uncorrected Stroboscopic stimulation: NVH > VH: L IPL, R cingulate gyrus VH > NVH: R IFG, R caudate nucleus Kinematic stimulation: NVH > VH: R middle temporal/occipital lobe, R cingulate gyrus, bilat. SG, L IPL VH > NVH: L SFG SMV during apparent kinematic stimulation, p < 0.05 corrected VH < NVH: area V5/MT |
| 12 PD NVH | 73.25 (7.58) | 11.17 (3.90) | 27.96 (2.09) | 3 (2–4) | ||||
| Taylor et al. (2012) [23] | 17 DLB | 81.2 (5.6) | 45.4 (32.2) 7,15 | NPI | 18.8 (5.1) | NA | Task-based fMRI Passively view of simple visual stimuli (checkboards, pictures of objects, moving dot fields); block design; whole brain analysis; ROIs: V5/MT, V1, V2, and V3 combined, ROI in the lateral occipital cortex; correlation between fMRI beta values in the ROIs and NPIhall ASL-MRI Perfusion; voxel-based analysis; ROI: same as fMRI analysis, precuneus and superior lateral occipital region; correlation between ASL perfusion and NPIhall |
fMRI activations No correlation with NPIhall Perfusion Negative association with NPIhall: V4 perfusion |
| 19 HC | 77.6 (7.1) | - | 29.0 (1.2) | |||||
| Uchiyama et al. (2015) [68] | 11 PD VH | 68.3 (1.6) 2 | 6.2 (1.1) 2 | NPI | 27.6 (0.6) 2 | 3.0 (2, 4) 3 | FDG-PET Covariates: age and sex; whole brain correlation analysis with NPIhall |
Glucose cerebral metabolic rate p < 0.001 uncorrected Negative correlation with NPIhall: metabolism in the L IPL |
| 42 PD NVH | 65.5 (1.0) | 6.3 (0.6) | 28.2 (0.3) | 2.5 (1, 4) | ||||
| 24 HC | 68.0 (1.0) | - | 28.6 (0.3) | - | ||||
| Yao et al. (2016) [22] | 12 PD VH | 70 (64, 72.75) 2, 11 | 9.1 (3.5) 2 | PPRS VH duration: 2.4 (1.1) years |
28.5 (24, 29.75) 2, 11 | 3.1 (0.7) 2 | Resting-state fMRI Seed-based approach: hippocampus FC; covariates: age, MMSE; correlation between cognitive tests and mean FC scores in clusters where FC was different between VH and NVH (controlling for age and visual accuracy scores) Structural MRI and DTI (ROI) 6 |
Functional connectivity of the hippocampus p < 0.05 corrected VH < NVH: R hippocampus: occipital, temporal regions; L hippocampus: temporal, occipital regions, and cerebellum VH > NVH: R hippocampus: frontal and temporal regions; L hippocampus: frontal and parietal regions Negative correlation between R hippocampal FC with R occipital gyrus, and medial temporal lobe and visuospatial memory performance |
| 15 PD NVH | 66 (62, 72) 11 | 7.1 (5.1) | 29 (28, 30) 11 | 2.9 (0.7) | ||||
| 14 HC | 63 (62, 68.75) 11 | - | 29 (28, 29.25) 11 | - | ||||
| Yao et al. (2015) [60] | 12 PD VH | 67.6 (7.4) 2 | 10.0 (3.5) 2 | PPRS VH duration: 22.6 (17.3) months |
27.6 (2.4) 2 | 3.2 (0.7) 2 | Resting-state fMRI ALFF; FC seed-region based on ALFF analysis (occipital lobe) |
ALFF p < 0.05 corrected VH < NVH: occipital lobe: LG, cuneus bilaterally VH > NVH: R cerebellum posterior lobe, MTL, IPL/STL Functional connectivity of occipital seed-region VH > NVH: bilat. IFG, SFG, MFG, medial frontal gyrus and STL; R STG, caudate/thalamus, dorsal anterior cingulate cortex/ventral medial PFC |
| 12 PD NVH | 63.4 (7.4) | 8.4 (5.1) | 28.5 (1.7) | 2.8 (0.9) | ||||
| 14 HC | 64.1 (4.0) | - | 29.1 (0.7) | - | ||||
| Yao et al. (2014) [17] | 12 PD VH | 67.6 (7.4) 2 | 10.0 (3.5) 2 | PPRS VH duration: 22.6 (17.3) months |
27.6 (2.4) 2 | 3.2 (0.7) 2 | Resting-state fMRI Covariates: age, MMSE score, and levodopa-equivalent dosage; ICA (40 components) FC in the DMN; group comparison; correlation between VH sev. and FC in the clusters that differed between PD groups Cortical thickness 6 |
Functional connectivity in the DMN p < 0.05 corrected VH > NVH: L and R precuneus/ PCC, R superior middle frontal lobe No correlation with VH |
| 12 PD NVH | 63.4 (7.4) | 8.4 (5.1) | 28.5 (1.7) | 2.8 (0.9) | ||||
| 14 HC | 64.1 (4.0) | - | 29.1 (0.7) | - |
1 Mean (SD); 2 no significant differences between groups; 3 VH ≠ NVH; 4 no differences between sPD VH and sPD NVH; 5 sPD VH and NVH ≠ ePD; 6 structural neuroimaging is reported in Table A1; 7 months; 8 Telephone Interview for Cognitive Status; 9 median (range); 10 one year before the development of VH, while three years after was 23; 11 median (interquartile range); 12 differences between groups; 13 VH ≠ HC; 14 MoCA; 15 duration of dementia. ACC: anterior cingulate cortex; AD: Alzheimer’s disease; ALFF: amplitude of low-frequency fluctuation; ASL: arterial spin labelling; BOLD: blood-oxygenation level-dependent; BPP: bistable percept paradigm; CAMCOG: Cambridge cognitive examination; ChEI: cholinesterase inhibitor; CI: cognitive impairment; CIS: cingulate island sign; DAN: dorsal attention network; DLB: dementia with Lewy bodies; DMN: default mode network; DTI: diffusion tensor imaging; ed.: education; ePD: early PD; fALFF: fractional amplitude of low-frequency fluctuation; FC: functional connectivity; FDG: [18F]-Fluorodeoxyglucose; freq.: frequency; FG: fusiform gyrus; fMRI: functional MRI; H&Y: Hoehn and Yahr stage; HDRS: Hamilton depression rating scale; hypermetab.: hypermetabolism; ICA: independent component analysis; IFG: inferior frontal gyrus; IOG: inferior occipital gyrus; IPL: inferior parietal lobule; ITG: inferior temporal gyrus; L: left; LG: lingual gyrus; LGN: lateral geniculate nucleus; LPC: lateral parietal cortex sPD; MFG: middle frontal gyrus; MMSE: Mini-Mental State Examination; MoCA: Montreal Cognitive Assessment; MOG: middle occipital gyrus; MRI: magnetic resonance imaging; MSA: multiple system atrophy; MTG: middle temporal gyrus; MTL: medial temporal lobe; NA: not available; nBPP; NPI: Neuropsychiatric Inventory; NPIhall: NPI hallucination score; NS: not significant; NVH: no VH; pBPP: positive bistable percept paradigm; PCC: posterior cingulate cortex; PD: Parkinson’s disease; PDD: Parkinson’s disease dementia; PET: positron emission tomography; PFC: prefrontal cortex; R: right; ROI: region of interest; sev.: severity; SFS: superior frontal sulcus; SG: supramarginal gyrus; STG: superior temporal gyrus; STL: superior temporal lobe; SUVR: standardized uptake value ratio; SVC: small volume correction; TMT: trial making test; UPDRS: Unified Parkinson’s Disease Rating Scale; VAN: ventral attention network; VH: visual hallucinations; VIS: visual network.