The present review is concerned with the role of different physiological systems (e.g., skin conductance, heart rate, electromyography, and the eye-bling startle reflex) in understanding heterogeneity in conduct disorder (CD). Four subtyping approaches are considered: age of onset, comorbid psychopathology, callous-unemotional traits, and proactive/reactive aggression. Empirical findings are discussed in terms of distinct theoretical perspectives that aim to explain CD behaviors based on physiological over-arousal, under-arousal, and empathy deficits. According to the studies reviewed, the callous-unemotional (CD + CU) and internalizing (CD + Internalizing) sub-types can best inform CD heterogeneity. Findings indicated that children in the CD + CU and CD + Internalizing subtypes score on opposite extremes on heart rate, skin conductance and startle reactivity measures. Heart rate variability and respiratory sinus arrhythmia dysfunctions, associated with emotional dysregulation, were more evident among children in the CD + Internalizing group, while dysfunctional facial electromyography activity, which has been linked with reduced empathy, with the CD + CU group. In conclusion, it might be important to redefine CD diagnostic criteria based on physiological heterogeneity to enable the identification of distinct subtypes of CD.

本文涉及不同的生理系统（例如，皮肤电导，心率，肌电图和眨眼的惊吓反射）在理解行为障碍（CD）异质性中的作用。考虑了四种分型方法：发病年龄，共病的精神病理学，无情的情绪低落特征和积极/积极的攻击性。根据不同的理论观点讨论了经验发现，这些理论观点旨在解释基于生理过度兴奋，听力不足和共情缺陷的CD行为。根据所审查的研究，无情的（CD + CU）和内在的（CD +内在的）亚型可以最好地说明CD的异质性。研究结果表明，CD + CU和CD +内在化亚型的儿童在心率上处于相反的极端水平，皮肤电导和惊吓反应性措施。CD +内化组儿童的心率变异性和呼吸窦性心律失常功能障碍与情绪失调有关，在CD + CU组儿童面部肌电图功能异常（与移情减少有关）方面更为明显。总之，基于生理异质性重新定义CD诊断标准以识别CD的不同亚型可能很重要。