Support for a Transdiagnostic Motivational Model of Self-Damaging Behaviors: Comparing the Salience of Motives for Binge Drinking,Disordered Eating,and Nonsuicidal Self-Injury

Integrating across motivational models suggests that different self-damaging behaviors (SDBs) are enacted for similar reasons. However, it remains unclear whether some motives are more relevant to certain SDBs than others. To answer this question, the present study compared the salience of 8 potentially shared motives across 3 exemplar SDBs, selected to represent different points along the internalizing and externalizing spectra: binge drinking, disordered eating (binge eating, purging, fasting), and nonsuicidal self-injury (NSSI). Seven hundred and four first-year university students (73% female, M_age = 17.97) completed monthly surveys assessing their engagement in and motives for SDBs. Motives were conceptualized as either interpersonal (bonding with others, conforming with others, communicating strength, communicating distress, reducing demands) or intrapersonal (reducing negative emotions, enhancing positive emotions, punishing oneself). Multilevel models compared endorsement of each motive across SDBs. Results revealed that SDBs were motivated by similar goals, albeit to different degrees. Although some exceptions emerged, interpersonal motives were most salient to binge drinking, followed by disordered eating, and then NSSI. In contrast, intrapersonal motives were most salient to NSSI, followed by disordered eating, and then binge drinking. Motivational differences were also found within disordered eating. For example, punishing oneself was more relevant to purging and fasting than binge eating, whereas relieving negative emotions was more relevant to binge eating and purging than fasting. Similar to dimensional models that position SDBs on internalizing or externalizing spectra, the salience of motives for binge drinking and NSSI may fall on distinct spectra (i.e., interpersonal and intrapersonal, respectively), with motives for disordered eating exhibiting elements consistent with both spectra. This study supports a common motivational framework for investigating and potentially treating a variety of topographically distinct SDBs.