Abstract
IMPORTANCE: Nonsuicidal self-injury (NSSI) is a significant clinical concern among adolescents. Exposure to NSSI-related content on social media platforms has been suspected to potentially act as a trigger for NSSI. OBJECTIVE: To use free-viewing eye-tracking and dot-probe paradigms to examine attentional bias and psychophysiological responses to NSSI-related pictorial and textual stimuli in adolescents with and without a history of NSSI. DESIGN, SETTING, AND PARTICIPANTS: From June 2022 to April 2023, adolescent participants in Vienna, Austria with and without a history of NSSI were exposed to NSSI-related stimuli in this nonrandomized controlled trial. Data were analyzed from December 2023 to January 2024. EXPOSURE: Exposure to NSSI-related stimuli. MAIN OUTCOMES AND MEASURES: During both tasks, subjective arousal, NSSI urges, and autonomic nervous system activity were assessed. RESULTS: A total of 50 adolescents in 2 groups, 25 who engaged in NSSI (mean [SD] age 15.86 [1.14] years; 19 female participants [76%]) and 25 who did not (mean [SD] age 16.40 [1.71] years; 19 female participants [76%]) were included. Adolescents with a history of NSSI-but not those without a history of NSSI-showed a clear attentional bias toward NSSI-related images during eye-tracking, as indicated by increased initial fixations (500 ms stimulus presentation mean difference, 28.64%; 95% CI, 18.31%-38.98%; P < .001; 1000 ms stimulus presentation mean difference, 18.50%; 95% CI, 9.05%-27.95%; P < .001) and longer fixation durations (500 ms mean difference, 29.51 ms; 95% CI, 4.3-54.72 ms; P < .001; 1000 ms mean difference, 39.83 ms; 95% CI, 6.90-72.76 ms; P < .001), regardless of stimulus duration. This bias was associated with a heightened urge to engage in NSSI (d = 1.22; 95% CI, 0.69-1.73; P < .001), a trend not seen in adolescents without a history of NSSI. Similarly, in the dot-probe task, only the NSSI group showed an attentional bias toward NSSI images but not toward trauma images, emphasizing the specificity of their attentional bias. Physiological measures revealed no significant differences, suggesting that viewing NSSI images is not associated with increased autonomic arousal. Textual NSSI content did not provoke an attentional bias or heighten NSSI urges in either group. CONCLUSIONS AND RELEVANCE: In this nonrandomized controlled trial of 50 adolescents, results highlighted a specific attentional bias toward NSSI-related pictorial stimuli in adolescents with a history of NSSI, particularly a difficulty in disengaging from NSSI images. These findings contribute to understanding maladaptive information processing in NSSI and suggest implications for clinical management and cognitive models addressing NSSI triggers. TRIAL REGISTRATION: German Clinical Trials Register identifier: DRKS00025905.