Suicidality and Impulsivity

Prior research on suicide has cited impulsivity as a risk factor, yet little is known about the actual relationship between these variables. According to Joiner's (2005) interpersonal-psychological theory of suicidality, impulsive people are more likely than others to have habituated to extreme forms of pain and threat, accruing increased comfort with exposure to lethal self-injury. Joiner's (2005) theory proposes that the relationship between impulsivity and suicide is mediated by painful and provocative experiences that cause habituation, which in turn leads to the necessary acquired capability for suicide. We predicted that significant relationship will exist between trait impulsivity as measured by the Barratt Impulsivity Scale, behavioral impulsivity as measured by the Impulsive Behavior Scale, and three theoretically interrelated dependent measures: the Acquired Capability for Suicide Scale, pain threshold, and pain tolerance (as measured by a digital pressure algometer). We also predicted that scores on the Painful and Provocative Life Events Scale would mediate statistically significant relationships between trait impulsivity, behavioral impulsivity, and the acquired capability for suicide in an undergraduate sample (N=215). Behavioral Impulsivity significantly predicted the acquired capability for suicide, whereas trait impulsivity did not. Furthermore, painful and provocative life experiences fully mediated the relationship between behavioral impulsivity and the acquired capability for suicide. Results indicate that the relationship between behavioral impulsivity and acquired capability for suicide may be better explained by an individual's exposure to painful and provocative life events.