Altered Brain Functional Connectivity and Topological Structural in Girls with Idiopathic Central Precocious Puberty: A Graph Theory Analysis Based on Resting-State fMRI

Objectives: This study aimed to investigate changes in brain functional connectivity (FC) and topological structure in girls with idiopathic central precocious puberty (ICPP) using complex network theory analysis. Methods: Resting-state fMRI data from 53 ICPP girls (ages 6–8) and 51 controls were analysed. Graph theory was used to construct whole-brain functional networks, identify topological differences, and assess the relationship between sex hormone levels and network properties in regions with group differences. Results: RS-FC analysis revealed reduced connectivity in cognitive and emotional regulation regions in the ICPP group (p < 0.05), but enhanced connectivity in emotional perception and self-regulation areas, such as the amygdala and insula (p < 0.05), suggesting a compensatory mechanism. Graph theory showed that ICPP girls’ brain networks maintained small-world properties (γ > 1, λ ≈ 1, σ > 1). Local topological changes included decreased clustering and node efficiency in cognitive and emotional regulation regions, like the superior frontal gyrus and praecuneus (p < 0.05), while emotional regulation regions (amygdala, insula) showed increased clustering and node efficiency (p < 0.05), indicating compensation. Conclusions: This study highlights compensatory mechanisms in emotional regulation that may offset impairments in cognitive regions, offering new insights into ICPP’s neural mechanisms.