Clinical interest in nonsuicidal self-injury (NSSI) as a diagnosis in its own right has grown in recent years. Though NSSI has been popularly associated with attention-seeking behaviours and suicidal motives, it is most commonly used as a maladaptive coping mechanism to regulate high-arousal
negative emotion. This study took the first steps in formalizing a model of NSSI, applying the Theory Construction Methodology. First, the literature was reviewed to collect phenomena of interest (POI). The relations between these phenomena were subsequently linked through a causal loop diagram, which served as the prototheory. These links were formalized using differential equations, and simulated with the goal of reproducing the chosen POIs. Unlike previous computational models, the present study applied bottom-up formalization rather than the dominant approach of analogical abduction. A notable limitation of the model is its simplicity, producing some unrealistic dynamics in pain and NSSI. Nonetheless, this study provides valuable groundwork by explicitly testing the hypothesized relations between variables that often remain implicit in NSSI research.