The decision neuroscience perspective on suicidal behavior: Evidence and hypotheses

Purpose of review Suicide attempts are usually regretted by people who survive them. Furthermore, addiction and gambling are over-represented among people who attempt or die by suicide, raising the question whether their decision-making is impaired. Advances in decision neuroscience have enabled us to investigate decision processes in suicidal people and to elucidate putative neural substrates of disadvantageous decisionmaking. Recent findings Early studies have linked attempted suicide to poor performance on gambling tasks. More recently, functional MRI augmented with a reinforcement learning computational model revealed that impaired decision-making in suicide attempters is paralleled by disrupted expected value (expected reward) signals in the ventromedial prefrontal cortex. Behavioral studies have linked increased delay discounting to low-lethality/poorly planned attempts, multiple attempts, and the co-occurrence of attempted suicide and addiction. This behavioral tendency may be related to altered integrity of the basal ganglia. By contrast, well-planned, serious suicide attempts were associated with intact/diminished delay discounting. One study has linked high-lethality suicide attempts and impaired social decision-making. Summary This emerging literature supports the notion that various impairments in decision-making - often broadly related to impulsivity - may mark different pathways to suicide. We propose that aggressive and selfdestructive responses to social stressors in people prone to suicide result from a predominance of automatic, Pavlovian processes over goal-directed computations.