Neuropsychological Markers of Suicidal Risk in the Context of Medical Rehabilitation

Abstract

While great strides have been made to advance the understanding of the neurobiology of suicidal behavior (SB), the neural and neuropsychological mechanisms associated with SB are not well understood. The purpose of the current study is to identify neurocognitive markers of SB in the context of medical rehabilitation. The performances of 39 patients at a medical rehabilitation center, aged 21–78, were examined on a series of neurocognitive executive tasks–decision-making (Iowa Gambling Task – IGT), mental flexibility (WCST), response inhibition (SST) and working memory (digit span). Self-report questionnaires were administered, for Suicidal behaviors, depression, Anxiety, and PTSD as well as perceived social support. Suicidal participants performed more poorly on the IGT. A mediation analysis presented a significant direct effect of decision making on suicidal risk (p < 0.14) as well as significant indirect effect of decision making on suicidal risk that was mediated by the depressive symptoms (95% BCa CI [−0.15, −0.018]) with a medium effect size (κ2 = 0.20, 95% BCa CI [0.067, 0.381]). Despite the complexity of relationship between decision-making and suicidal risk, these results suggest that clinicians should routinely assess decision-making abilities in adults at risk for suicide due to the fact that impaired decision-making may increase suicidal risk above and beyond that conferred by depression.