Noise Pareidolia Test in Parkinson's Disease and Atypical Parkinsonian Syndromes: A Retrospective Study

Takuya Matsumoto; Jinsoo Koh; Mayumi Sakata; Yoshiaki Nakayama; Shoko Yorozu; Junko Taruya; Maiko Takahashi; Katsuichi Miyamoto; Hidefumi Ito

doi:10.7759/cureus.55436

Noise Pareidolia Test in Parkinson's Disease and Atypical Parkinsonian Syndromes: A Retrospective Study

Cureus. 2024 Mar 3;16(3):e55436. doi: 10.7759/cureus.55436. eCollection 2024 Mar.

Authors

Takuya Matsumoto¹, Jinsoo Koh¹, Mayumi Sakata¹, Yoshiaki Nakayama¹, Shoko Yorozu¹, Junko Taruya¹, Maiko Takahashi¹, Katsuichi Miyamoto¹, Hidefumi Ito¹

Affiliation

¹ Department of Neurology, Wakayama Medical University, Wakayama, JPN.

Abstract

Introduction: Pareidolias, or visual misperceptions, are a non-motor symptom of Parkinson's disease (PD) with unclear pathophysiology. The noise pareidolia test (NPT) is a tool for screening pareidolias. The usefulness of the NPT in differentiating PD from atypical parkinsonian syndromes (APS) is also unknown.

Methods: We retrospectively investigated 74 patients with PD and 18 patients with APS who took the NPT. Correlations between the number of pareidolic responses, gray matter volume, and cerebral blood flow were also examined in the patients with PD.

Results: The median number of pareidolic responses in patients with PD and patients with APS was 0 (interquartile range (IQR): 0-3) and 0 (IQR: 0-1), respectively, and tended to be higher in patients with PD than in those with APS (p = 0.077). It was significantly higher in patients with PD who had hallucinations (2; IQR: 0-9) (p = 0.016). The area under the receiver operating characteristic curve for the number of pareidolic responses in the NPT was 0.62 when used to differentiate PD and APS, and the optimal cutoff number of pareidolic responses was 2/3. Sensitivity and specificity were 25.7% and 100%, respectively. In the PD group, the number of pareidolic responses was correlated with age (r = 0.27; p = 0.021) and the Frontal Assessment Battery (FAB) score (r = -0.34; p = 0.0099). Magnetic resonance imaging showed no significant correlation between the number of pareidolic responses and the volume of focal gray matter. On cerebral hypoperfusion mapping, the left parietal lobe had a significant correlation with the number of pareidolic responses (r = 0.35; p = 0.027).

Conclusion: The number of pareidolic responses in NPT was suggested to be useful as a red flag to rule out APS in differentiating PD from APS. In PD without dementia, the number of pareidolic responses was associated with reduced blood flow in the left parietal lobe.

Keywords: atypical parkinsonian syndrome; noise pareidolia test; pareidolia; parkinson’s disease; visual hallucination; visual misperception.

Grants and funding

This work was supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI (grant number: JP21K13708). The funding source was not involved in the study design.