Whole-brain structural and functional neuroimaging of individuals who attempted suicide and people who did not: a systematic review, exploratory coordinate-based meta-analysis and seed-based connectivity study

IntroductionSuicide is the cause of death of approximately 800’000 people a year. Despite the relevance of this behaviour, risk assessment tools rely on clinician experience and subjective ratings.MethodsGiven that previous suicide attempts are the single strongest predictors of future attempts, we designed a systematic review and coordinate-based meta-analysis to evince if any neuroimaging features can help distinguish individuals who attempted suicide from subjects who did not. Out of 5659 publications from PubMed, Scopus and Web of Science, we summarised 102 experiments and meta-analysed 23 of them.ResultsA cluster in the right Superior Temporal Gyrus, a region implicated in emotional processing, might be functionally hyperactive in individuals who attempted suicide. Furthermore, we used JuSpace and the Human Brain Connectome dataset to show that this cluster is enriched in 5-HT1Aheteroreceptors, and its connectivity with the left central operculum is significantly correlated with loneliness scores.ConclusionsThis evidence provides a putative neural substrate for suicidal thought-to-attempt transition as hypothesised by Joiner’s Interpersonal Theory of Suicide. Heterogeneity in the analytical techniques and weak or absent power analysis of the studies included in this review currently limit the applicability of the findings, the replication of which should be prioritised.