Abstract:
Patients with Lewy body disease (LBD) frequently experience visual hallucinations (VH), well-formed images perceived without the presence of real stimuli. The structural and functional brain mechanisms underlying VH in LBD are still unclear. The present review summarises the current literature on the neural correlates of VH in LBD, namely Parkinson\'s disease (PD), and dementia with Lewy bodies (DLB). Following a systematic literature search, 56 neuroimaging studies of VH in PD and DLB were critically reviewed and evaluated for quality assessment. The main structural neuroimaging results on VH in LBD revealed grey matter loss in frontal areas in patients with dementia, and parietal and occipito-temporal regions in PD without dementia. Parietal and temporal hypometabolism was also reported in hallucinating PD patients. Disrupted functional connectivity was detected especially in the default mode network and fronto-parietal regions. However, evidence on structural and functional connectivity is still limited and requires further investigation. The current literature is in line with integrative models of VH suggesting a role of attention and perception deficits in the development of VH. However, despite the close relationship between VH and cognitive impairment, its associations with brain structure and function have been explored only by a limited number of studies.
摘要:
路易体病(LBD)患者经常会出现视觉幻觉(VH),在没有真实刺激的情况下感知到的形成良好的图像。LBD中VH的结构和功能脑机制尚不清楚。本综述总结了目前关于LBD中VH的神经相关性的文献,即帕金森病(PD),和路易体痴呆(DLB)。经过系统的文献检索,对PD和DLB中VH的56项神经影像学研究进行了严格审查和评估,以进行质量评估。LBD中VH的主要结构神经影像学结果显示痴呆患者额叶区域的灰质损失,PD的顶叶和枕部-颞区无痴呆。在幻觉性PD患者中也报告了顶叶和颞叶代谢减退。特别是在默认模式网络和顶叶区域中,检测到功能连接中断。然而,关于结构和功能连通性的证据仍然有限,需要进一步调查。目前的文献与VH的整合模型一致,表明注意力和感知缺陷在VH的发展中起作用。然而,尽管VH与认知障碍密切相关,它与大脑结构和功能的关系只有有限的研究。