Objective: To evaluate the prevalence of visual misperception in patients with PD (PwP) in comparison with healthy control (HC) and its association with visual hallucinations.
Background: Noise Pareidolia or misinterpreting ambiguous visual stimuli as meaningful objects, is a non-motor symptom of Parkinson’s disease (PD) that can be assessed using the Noise Pareidolia Test (NPT) and it is associated with visual hallucinations [1].
Method: This study is part of the London-Dhaka Parkinson’s Cognition Study (LDCS), which is a case-control study. For Dhaka cohort Patients with PD and HC were recruited from movement disorder clinics at Bangabandhu Sheikh Mujib Medical University Dhaka, Bangladesh. Data collection includes clinical and demographic information, MoCA, RUDAS, CDR, HADS, Cats & dog teat, Auditory test and NPT via MATLAB. The subjects are gradually presented with 40 images (30s each) including black-and-white patterns, and eight embedded with images of human faces. The subjects were instructed to answer whether a task image contained a human face. The outcome measures include ‘NPT_Correct’, in which the subjects correctly identified the faces or correctly responded that there were no faces; ‘NPT_pareidolia’, in which the subjects falsely identified faces that were not actually in the images; and NPT_Miss’, in which the subjects failed to detect the faces.
Results: In Dhaka since January 2023, 200 patients and 100 HC have been recruited. The mean age (±SD) of patients with PD was 60 (±10.5) years and for controls was 55.4 (±10.3); (p<0.001). Among them 142 (71%) PD and 61 (61%) HC were male (p=0.081). The mean NPT_Correct (±SD) were 32.4 (±11) and 36.6 (±8.1) in PD and HC respectively (p<0.001). The mean NPT_pareidolia (2.8±5.5;1±2.3) and NPT_Miss (1.5±1.7;0.6±1.0) were significantly higher in PD than HC group (p=0.006; p<0.001). In patients with PD with visual hallucinations, the mean NPT_Correct was significantly lower than in PD without visual hallucinations (25.52±16.98; 33.46±9.43; p<0.001). However, the mean NPT_Pareidolia and NPT_Miss showed no significant difference between PD with or without visual hallucinations.
Conclusion: This study showed that there was significant visual perception impairment in patients with PD compared to healthy control. Furthermore patients with visual hallucinations tend to score lower in terms of correctness than patients with no visual hallucinations.
References: 1. Pareidolias: complex visual illusions in dementia with Lewy bodies. Uchiyama M, Nishio Y, Yokoi K, Hirayama K, Imamura T, Shimomura T, Mori E. Brain. 2012;135:2458–2469. doi: 10.1093/brain/aws126.
To cite this abstract in AMA style:
T. Zannat, E. Camboe, K. Dey, A. Zirra, A. Haque, D. Mair, S. Waters, C. Marshall, N. Mukadam, R. Weil, A. Noyce, A. Habib. Evaluation Of Visual Perception Using Noise Pareidolia Test in Bangladeshi Patients with Parkinson’s disease. [abstract]. Mov Disord. 2025; 40 (suppl 1). https://www.mdsabstracts.org/abstract/evaluation-of-visual-perception-using-noise-pareidolia-test-in-bangladeshi-patients-with-parkinsons-disease/. Accessed November 20, 2025.« Back to 2025 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/evaluation-of-visual-perception-using-noise-pareidolia-test-in-bangladeshi-patients-with-parkinsons-disease/