Altered dynamic brain activity of recent suicidal ideation and suicidal attempt in depression patients and its relationship with cognitive function

Objective: The "ideation-to-action" framework for suicide posited that the occurrence of suicidal ideation (SI) and suicide attempts (SA) may involve distinct neural mechanisms. However, the disparities in neurocognitive impairment between SI and SA, along with the underlying neural mechanisms, remain further investigation. Methods: A total of 730 participants were recruited, including depressed patients with recent SA (RSA group, n = 69), patients with recent SI but no history of SA (SI group, n = 327), patients without SI or SA (NSI group, n = 87) and 247 healthy controls. All participants underwent resting-state functional magnetic resonance imaging (rsfMRI) scans and completed cognitive function assessments. The dynamic regional homogeneity (dReHo) was measured using a sliding-window approach. Differences in dReHo and cognitive function between groups were analyzed. Results: The SI group demonstrated decreased verbal memory compared to the NSI group. Critically, the RSA group exhibited more pronounced verbal memory impairment than the SI group, accompanied by deficits in working memory and cognitive flexibility. Neuroimaging results revealed elevated dReHo values in the right precuneus (PCUN.R) in the RSA group, distinguishing them from the SI, NSI, and HC groups. Additionally, the increased dReHo of PCUN.R was correlated with diminished cognitive performance. Conclusions: Depressed patients with SA showed elevated variability of functional activity in PCUN.R, which may be related to their more severe cognitive impairment. This may be a potential neural basis for the development of SA. Our findings offer new insights for advancing neuroscience research on the progression from SI to SA.