Extreme (“20”) self-shocks during the Self-Aggression Paradigm and lifetime suicide attempt history: Potential use in suicide research

Suicidal behavior and non-suicidal self-injury (NSSI) share many risk factors, correlates, and ethical and pragmatic barriers to research; thus, methods exploring one may provide indirect insights into the other. The Self-Aggression Paradigm (SAP) is a behavioral analog task for NSSI in the laboratory via self-administered shocks and has demonstrated associations with suicide risk factors. We compared behavior during the SAP between participants with a suicide attempt history (SA+; n = 88, women = 56, men = 32)-between 1 to 13 attempts (M = 1.3, SD = 0.705)-to those without (SA-; n = 654, women = 373, men = 281) using the number of highest available ("extreme") shocks selected and average shock selection. We predicted SA+ would select more extreme shocks and higher average shocks and this would remain true for extreme shocks but not average shock selection after controlling for NSSI history. General linear model analyses revealed that SA+ selected more extreme shocks overall and higher average shocks compared to SA- with small effect sizes. This remained true after controlling for NSSI history; however, effect sizes were negligible after including NSSI Our results provide some evidence supporting using the SAP in studies on suicidal behavior, albeit with small effect sizes. Future research may benefit from comparing SAP behavior between participants with a recent suicide attempt versus those with more remote histories of suicidal behavior, as well as recruiting for more NSSI behavior for further comparisons.