Validation of an fMRI measure of Real Time Non-Suicidal Self-Injury

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Non-suicidal self-injury (NSSI), the direct and deliberate destruction or alteration of body tissue without suicidal intent, is a major public health issue that can lead to severely disabling outcomes including permanent physical injuries and recurrent hospitalizations. Furthermore, NSSI and related acts of produce a great societal cost, with medical treatment and lost productivity alone summing to approximately $33 billion dollars per year. Neuroimaging studies also show cortico-limbic differences between individuals with and without a history of NSSI the on tasks of emotion regulation and physical pain, most notably the prefrontal cortex and amygdala. However, to date no studies have directly examined the neurocircuitry of in-vivo NSSI behavior. This is in large part due to the dearth of fMRI tasks of in-vivo NSSI. The Self Aggression Paradigm (SAP) is a behavioral NSSI task that uses self-selected shock as an NSSI analogue. In addition to being one of the very few validated NSSI behavioral tasks, the SAP is the only NSSI analogue in which both the decision to self-harm as well as the intensity of self-harm is completely under the control of the participant, as it is in actual NSSI. The SAP has been used to identify the causal relationship between putative risk factor for NSSI (e.g. alcohol intoxication, depression, serotonin depletion) and self-harm. To address the need to directly study brain mechanisms involved in NSSI and changes in NSSI in real time, the research team has developed an fMRI version of the SAP. The study proposed in this application would allow us to (1) assess the validity of the fMRI-SAP and (2) conduct a pilot examination of neural activation and connectivity patterns associated with real time self-harm among individuals with (and without) a clinically significant NSSI history. Thirty participants with NSSI disorder (NSSI+: n= 30) and 30 matched participants with no history of NSSI (NSSI+: n =30) will complete a clinical interview assessing psychopathology (including NSSI disorder) followed by self-report measures of NSSI- related risk factors and a behavioral measure of pain tolerance. Participants will then undergo a brief mood induction to acutely increase negative affect (a common antecedent of NSSI) followed by functional neuroimaging during the fMRI SAP. We hypothesize that NSSI participants will select higher shocks on the fMRI SAP and that among those with NSSI, the level of self-shock will correlate with NSSI severity (evidence of fMRI–SAP validity). We also hypothesize there will be decreased prefrontal and increased amygdala activation as well as decreased orbitofrontal-anterior cingulate and orbitofrontal-amygdala connectivity for NSSI+ (vs NSSI-) participants on shock trials on the fMRI-SAP.