Functional Connectivity and White Matter Microstructural Alterations of Thalamic Subregions in Benign Paroxysmal...

Benign Paroxysmal Positional Vertigo (BPPV) is a common peripheral vestibular disorder. Although the thalamus serves as a key node in vestibular pathways, its role in the central regulation of BPPV remains unclear. This study aimed to explore the functional and structural alterations of thalamus in patients with BPPV.

The study recruited 52 BPPV patients and 52 age- and gender-matched healthy volunteers. Seed-based analysis was used to explore functional connectivity (FC) alterations between thalamic subregions and the whole brain in patient group. Probabilistic fiber tracking was then employed to analyze white matter structural differences in brain regions with functional alterations. Additionally, correlation analysis was conducted to investigate the relationship between abnormal imaging metrics and clinical scales.

Compared to controls, patients with BPPV exhibited increased FC and higher fractional anisotropy (FA) values of some thalamic subregions to certain cerebral cortices. As a confirmatory finding, decreased FC but increased structural connectivity was displayed between the rostral temporal thalamus and cerebellum in BPPV. Furthermore, the FA value of the rostral temporal thalamus-cerebellar tract showed a correlation with the score of the impact of event scale. The mediation analysis showed emotional distress mediated the relationship between vertigo and FA of the rostral temporal thalamus-cerebellar tract.

In BPPV, the thalamic subregions and certain cerebral cortices exhibit synergistic functional and structural enhancement, whereas a distinct dissociation pattern is observed in the cerebellum. This differentiated reorganization may characterize the neural process in the early stage of BPPV.