Spontaneous eye behavior is an objective marker of parkinsonian severity

Verma, A. K.; Nandakumar, B.; Feragen, Q. V.; Acedillo, K.; Hjelle, N.; Hendrix, C. M.; Duffy, K.; Fiecas, M.; Yu, Y.; Mohanty, B.; Wang, J.; Vitek, J. L.; Johnson, L. A.

doi:10.64898/2026.09.24.754183

bioRxiv · 10.64898/2026.09.24.754183

Spontaneous eye behavior is an objective marker of parkinsonian severity

Verma, A. K.·Nandakumar, B.·Feragen, Q. V.·Acedillo, K.·Hjelle, N.·Hendrix, C. M.·Duffy, K.·Fiecas, M.·Yu, Y.·Mohanty, B.·Wang, J.·Vitek, J. L.·Johnson, L. A.

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Abstract

Eye behavior disruption is reported in Parkinson's disease (PD), but its correlation with disease severity has not been well examined. Here, in a nonhuman primate model of PD, we show that spontaneous eye behavior is impaired in parkinsonism and correlates with clinical rating scores and subthalamic beta oscillatory activity. These findings suggest that spontaneous eye behavior could serve as an objective, non-invasive biomarker of parkinsonian severity.

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Verma, A. K., Nandakumar, B., Feragen, Q. V., Acedillo, K., Hjelle, N., Hendrix, C. M., Duffy, K., Fiecas, M., Yu, Y., Mohanty, B., Wang, J., Vitek, J. L., Johnson, L. A.. 2026-09-30. Spontaneous eye behavior is an objective marker of parkinsonian severity. https://doi.org/10.64898/2026.09.24.754183

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