Neuroanatomical and neurochemical substrates for visual hallucinations

视幻觉是自发现象，在实验环境中很难检测到。唤起视觉幻觉的工具将使功能性神经成像调查和治疗干预研究成为可能。我们之前设计了一个新的实验任务来检测和测量路易体痴呆和帕金森病患者的幻觉样幻觉。在本研究中，我们开发了另一种唤起视觉错觉的任务，该任务更容易管理，评分系统也更简单。使用这种新的测试，我们成功地在DLB患者中引起了幻觉样的错觉反应。多奈哌齐（一种胆碱酯酶抑制剂）的使用显著减少了幻觉反应的数量。提示DLB患者视幻觉与胆碱能不足之间的关系。

Visual hallucinations are spontaneous phenomena and hard to detect in experimental settings. Tools to evoke visual hallucinations would enable functional neuroimaging investigations and therapeutic intervention studies. We previously devised a new experimental task to detect and measure hallucination-like illusions in patients with dementia with Lewy bodies (DLB) and Parkinson's disease. In the present study, we developed another task to evoke visual illusions, which is easier to administer and has simpler scoring system. Using this new test, we successfully evoked hallucination-like illusory responses in patients with DLB. The number of illusory responses was dramatically reduced by administration of donepezil, a cholinesterase inhibitor. The result suggests the relationship between visual hallucinations and cholinergic insufficiency in DLB.