Physiological arousal and subjective appraisal were compared between controls and participants with Borderline Personality Disorder (BPD), in the context of a personally relevant imagery: Nonsuicidal self injury, suicide attempt, and stressful event. BPD participants were more aroused compared to controls at resting state. BPD also exhibited less emotional activities during the suicide attempt and self-harm imagery, as characterized by one of the physiological indicators, and decreased in negative emotions and urges to self-harm. Together, these findings revealed the reinforcing quality of parasuicide, and suggested an underlying difference in physiology and capacity to regulate emotions between BPD and controls.