Early Adolescent Non-Suicidal Self-Injury and Sensory Preference Differences: An Exploratory Study

Early Adolescent Non-Suicidal Self-Injury and Sensory Preference Differences: An Exploratory Study by Jacquelyn S. Christensen Claremont Graduate University: 2012 BACKGROUND: Non-suicidal self-injury (NSSI) occurs in 13% to 20% of adolescents, and is often indicative of deeper internal or social problems. A close review of current explanatory models of NSSI suggested that underlying individual sensory preferences may contribute substantial explanations for the self-regulatory functions of NSSI, as well as have implications for treatment approaches. In the context of integrating sensory processing models with prominent functional NSSI models, this dissertation research compared sensory preferences in youth who engaged in NSSI to sensory preferences of youth who did not engage in NSSI. OBJECTIVE: NSSI-engaging youth were hypothesized to have lower threshold sensory preferences (sensation avoiding and sensory sensitive), and higher sensitivity (low threshold) in touch processing, auditory processing, and modulation of sensory input affecting emotional response. Sensory preferences were hypothesized to predict NSSI functionality, and trauma history and symptomology were hypothesized to predict NSSI and sensory preferences. METHODS: Youth (n = 108; 56% female; 43% Hispanic) aged 8-14 completed selfreport items regarding knowledge, thoughts, and engagement in NSSI, the Functional Assessment of Self-Mutilation (FASM) to evaluate type and functionality of NSSI, and the Adolescent / Adult Sensory Profile to evaluate sensory preferences (low registration, sensation seeking, sensory sensitive, sensation avoiding). Parents (90% female; Mage = 39.4 (SD = 6.9)) completed the Sensory Profile as a secondary measure of youth sensory preferences and the UCLA post-traumatic stress disorder reaction index (PTSD-RI) to evaluate youth trauma history and symptomology. RESULTS: NSSI-engaging youth (N = 14) scored significantly higher than Non-NSSIengaging youth (N = 85) in the sensation avoiding (Cohen’s d = .83) and low registration (Cohen’s d = .66) domains. Auditory sensitivity (youth-reported) significantly predicted NSSI after controlling for age. While parent-reported sensory preferences and trauma history and symptomology were not predictive of NSSI, auditory sensitivity (parent-reported) predicted PTSD symptomology in youth with trauma history. CONCLUSIONS: Results provide preliminary insight into better understanding the selfregulatory role of NSSI, and offer insight into specific sensory preferences of young adolescents who engage in NSSI. In combination with future research, findings contribute to existing comprehensive models of NSSI, and provide evidence for sensory considerations in NSSI treatment. DEDICATION In memory of Dr. Enid Gruber, my mentor and friend, who nurtured my love of research and learning. I will always remember our trip to Hawaii for my first conference. Even though you are gone, I know you are proud of me. For Dr. Joye Swan who told me to ask myself, “What would I do today if I was brave?” And to all of those who struggle with self-injury. This, and much of my future research, is for you.