Illusory responses across the Alzheimer’s disease spectrum and Lewy body disease spectrum

Pareidolias are specific illusions of faces and objects perceived in formless visual stimuli. In studies using a noise pareidolia task in patients with clinical dementia, Dementia with Lewy Bodies patients report more illusory responses than Alzheimer’s disease patients, which correlates with severity of visual hallucinations (Yokoi et al., 2014). However, it is unknown whether illusory responses occur in earlier stages of disease or in non‐hallucinating patients across the Lewy body disease (LBD) spectrum, such as Parkinson’s Disease with and without cognitive impairment.