Emotional memory biases in bipolar depressed patients with high suicide risk

Emotional memory bias, a neurocognitive deficit commonly observed in mood disorders, refers to the tendency to remember emotionally charged information more precisely than healthy individuals. While this phenomenon has been explored in various psychiatric conditions, its specific relationship with suicide risk in patients with bipolar disorder during major depressive episodes remains unknown. Given the high prevalence of suicide in bipolar disorder, this study sought to examine the association between emotional memory bias and suicide risk in patients with bipolar depression. A recognition memory task was utilized, where participants (51 high-risk, 21 low-risk) viewed words with positive or negative valence and later identified whether they had been previously presented. Mixed-model analyses of covariance, controlling for age and depression severity, revealed that the high-risk group demonstrated a stronger bias toward negative stimuli. They exhibited more accurate recognition of negative words ("hits") and a higher tendency to incorrectly identify non-presented negative words as presented ("false alarms") compared to the low-risk group. These findings suggest that heightened emotional memory bias, particularly toward negative information, may be a key cognitive marker of suicide risk in patients with bipolar depression. Understanding this bias may inform targeted interventions aimed at reducing suicide risk in this population.