AIM To investigate whether the core of the pathophysiology underlying non-suicidal self-injury (NSSI) relates to poor impulse control due to impaired motor inhibition (i.e. the ability to inhibit a preplanned motor response). METHOD We conducted a case-control study to compare the proficiency of two domains of motor inhibition, that is, reactive and proactive inhibition, by giving the reaching arm version of the stop-signal task and a go-only task to 28 drug-naive adolescents with NSSI disorder (NSSID) (mean age [SD] 15 years 8 months [1 year 4 months]; three males and 25 females) and 28 typically developing adolescents (mean age 15 years 8 months [1 year 5 months]; three males and 25 females). RESULTS Reactive inhibition, as determined by the duration of the stop-signal reaction time, was enhanced in adolescents with NSSID compared to typically developing controls (194.2 [22.5 ms] vs 217.5 [17.3 ms], p < 0.001). By contrast, proactive inhibition was similar in both groups. Lastly, the level of impulsivity, assessed using the Barratt Impulsiveness Scale Version 11, did not differ between typically developing adolescents and adolescents with NSSID. However, adolescents with NSSID were more impulsive than controls in a subscale of the UPPS-P Impulsive Behavior Scale. INTERPRETATION NSSID is not driven by heightened motor impulsivity. Instead, adolescents with NSSID exhibited greater proficiency in reactive inhibition, a proxy for motor impulsivity. We suggest that the enhancement of reactive inhibition strengthens action control, allowing adolescents to suppress their self-protection instinct and perform NSSI behaviours.

中文翻译：

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患有非自杀性自伤障碍的青少年的反应性抑制增强。

目的 探讨非自杀性自伤 (NSSI) 病理生理学的核心是否与运动抑制（即抑制预先计划的运动反应的能力）受损导致的冲动控制不良有关。方法 我们进行了一项病例对照研究，通过向 28 名未曾接受药物治疗的受试者提供伸臂版本的停止信号任务和只走任务，比较运动抑制的两个领域（即反应性抑制和主动性抑制）的熟练程度。患有 NSSI 障碍 (NSSID) 的青少年（平均年龄 [SD] 15 岁 8 个月 [1 年 4 个月]；三名男性和 25 名女性）和 28 名典型发育青少年（平均年龄 15 岁 8 个月 [1 年 5 个月]；三名男性 25 名女性）。结果 与典型发育对照相比，NSSID 青少年的反应性抑制（根据停止信号反应时间的持续时间确定）增强（194.2 [22.5 ms] vs 217.5 [17.3 ms]，p < 0.001）。相比之下，两组的主动抑制相似。最后，使用 Barratt 冲动量表第 11 版评估的冲动水平在正常发育的青少年和患有 NSSID 的青少年之间没有差异。然而，在 UPPS-P 冲动行为量表的子量表中，患有 NSSID 的青少年比对照组更容易冲动。解释 NSSID 不是由增强的运动冲动驱动的。相反，患有 NSSID 的青少年在反应性抑制（运动冲动的代表）方面表现出更高的熟练程度。我们认为反应性抑制的增强会加强行动控制，使青少年能够抑制自我保护本能并进行 NSSI 行为。