Attentional bias to death-related stimuli: Modeling cortical dynamics underlying suicide risk

This study used magnetoencephalography (MEG) and the life/death dot-probe task to investigate neural correlates of suicide risk, specifically whether suicide risk moderates selective attention to death-related cues. Three groups were examined: individuals with a lifetime history of suicide attempt or ideation (suicide risk; n = 17); those with depression but no suicide risk (clinical controls; n = 17); and healthy volunteers (n = 19). Individuals with suicide risk exhibited decreased activity in the superior parietal lobule (SPL), entorhinal cortex (EC), and middle temporal gyrus (MTG) in the death and incongruent conditions across multiple bandwidths (ps < 0.05), indicating suicide risk-associated dysregulation of brain regions related to signal processing. Dynamic causal modeling was used to estimate effective connectivity. In the death condition, reduced feedforward connectivity was observed from the early visual cortex to the EC, then to the SPL, and finally to the MTG in the suicide risk group (posteriorps > 0.90), suggesting potential deficits in updating sensory inputs and regulating selective attention. Conversely, in the life condition, reduced connectivity was observed from the MTG to the SPL in the suicide risk group (posteriorps > 0.90), suggesting subtle impairments in downregulating attention orientation during life-related cognitive processes. Abnormalities in selective attention to death-related cues may serve as potential biomarkers for suicide risk.