Schedule of Events | Symposia

Altered spatiotemporal connectivity patterns and diminished higher-order information exchange in Parkinson’s patients with hyposmia

Poster Session D - Monday, March 31, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Sneha Ray¹ (sneha.ray@ucsf.edu), Navkiran Kalsi², Henning Boecker³, Neeraj Upadhyay³, Rajanikant Panda¹; ¹University of California San Francisco, ²O.P. Jindal Global University, ³University of Bonn

Background and aim: Hyposmia is one of the common non-motor symptoms related to loss of olfaction in Parkinson's disease (PD) and olfactory dysfunction is associated with perturbation of higher order cognitive functioning. While structural and functional brain changes in PD patients with hyposmia are well-documented, exploring the dynamic nature of brain states could enhance understanding of abnormalities in cognitive information exchange. Methods: Structural and functional MRI of PD patients 15 with severe-hyposmia (PD-SH), 15 with cognitive normal ability (PD-CN) and 15 healthy controls (HC) were selected from an open-source study database. We assessed the dynamic brain state (spatiotemporal connectivity pattern), which characterizes brain's spontaneous spatiotemporal network alterations, and synergy & redundancy which capture brain’s capacity for higher-order information exchange. Results: A dynamic brain state that consists of complex, long-range-global connections was significantly decreased in PD-SH and PD-CN only when compared to HC. However, another brain state, which has prominent modular-local clusters consisting of sensorimotor and frontal areas, has an increased probability of occurrences in the patient's group PD-SH compared to PD-CN. Furthermore, the higher-order information flow was reduced significantly in the bilateral superior-temporal and parahippocampus areas in the PD patients (both PD-CN and PD-SH) compared to HC. Though no significant differences were found, however, PD-SH showed a larger reduction in higher-order information flow in the bilateral frontal, insula and left sensory-motor areas then PD-CN. Conclusion: PD patients with hyposmia showed disruption of spatiotemporal functional connectivity and reduced higher-order information exchange, which could potentially discriminate PD with hyposmia to cognitively-normal PD.

Topic Area: METHODS: Neuroimaging