Background Current neurobiological models of post-traumatic stress disorder (PTSD) assume excessive medial frontal activation and hypoactivation of cortico-limbic regions as neural markers of post-traumatic dissociation. Script-driven imagery is an established experimental paradigm that is used to study acute dissociative reactions during trauma exposure. However, there is a scarcity of experimental research investigating neural markers of dissociation; findings from existing script-driven neuroimaging studies are inconsistent and based on small sample sizes. Aims The current aim was to identify the neural correlates of acute post-traumatic dissociation by employing the script-driven imagery paradigm in combination with functional magnetic resonance imaging. Method Functional neuroimaging data was acquired in 51 female patients with PTSD with a history of interpersonal childhood trauma. Blood-oxygen-level-dependent response during the traumatic (versus neutral) autobiographical memory recall was analysed, and the derived activation clusters were correlated with dissociation measures. Results During trauma recall, enhanced activation in the cerebellum, occipital gyri, supramarginal gyrus and amygdala was identified. None of the derived clusters correlated significantly with dissociative symptoms, although patients reported increased levels of acute dissociation following the paradigm. Conclusions The present study is one of the largest functional magnetic resonance imaging investigations of dissociative neural biomarkers in patients with PTSD undergoing experimentally induced trauma confrontation to elicit symptom-specific brain reactivity. In light of the current reproducibility crisis prominent in neuroimaging research owing to costly and time-consuming data acquisition, the current (null) findings highlight the difficulty of extracting reliable neurobiological biomarkers for complex subjective experiences such as dissociation.

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Background : Research suggests dissociation and insecure attachment serve as explanatory mechanisms in the pathway from childhood trauma to paranoia. However, past work has not examined these mechanisms concurrently in nonclinical populations. Objective : The current study sought to examine dissociation and insecure attachment as parallel mediators of the association between childhood emotional abuse and paranoid traits. Furthermore, a serial mediation model with insecure attachment preceding dissociation in the explanatory pathway was explored. Methods : Eighty-nine nonclinically ascertained young adults were assessed for childhood emotional abuse, dissociation, attachment styles, and paranoid traits. Parallel and serial mediation models were tested. Results : The association of childhood emotional abuse with both interview-based and self-reported paranoid traits was significantly mediated by dissociation and preoccupied attachment. Fearful attachment was a significant mediator in the model for self-reported paranoid traits. No evidence for a serial mediation effect was found. Conclusions : The present findings extend support for dissociation and attachment insecurity as mechanisms underlying the link between childhood emotional maltreatment and paranoid traits. Longitudinal research is needed to inform whether insecure attachment contributes to dissociation along the pathways to paranoid traits.

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Background: Neurophysiological models link dissociation (e.g. feeling detached during or after a traumatic event) to hypoarousal. It is currently assumed that the initial passive reaction to a threat may coincide with a blunted autonomic response, which constitutes the dissociative subtype of post-traumatic stress disorder (PTSD). Objective: Within this systematic review we summarize research which evaluates autonomic nervous system activation (e.g. heart rate, blood pressure) and dissociation in PTSD patients to discern the validity of current neurophysiological models of trauma-related hypoarousal. Method: Of 553 screened articles, 28 studies (N = 1300 subjects) investigating the physiological response to stress provocation or trauma-related interventions were included in the final analysis.Results: No clear trend exists across all measured physiological markers in trauma-related dissociation. Extracted results are inconsistent, in part due to high heterogeneity in experimental methodology. Conclusion:The current review is unable to provide robust evidence that peri-and posttraumatic dissociation are associated with hypoarousal, questioning the validity of distinct psychophysiological profiles in PTSD.La disociación relacionada con el trauma y el sistema nervioso autónomo: Una revisión bibliográfica sistemática de los correlatos psicofisiológicos de la experiencia disociativa en pacientes con TEPT Antecedentes: Los modelos neurofisiológicos vinculan la disociación (por ejemplo, la sensación de desapego durante o después de un evento traumático) con la hipoactivación. Actualmente se asume que la reacción pasiva inicial ante una amenaza puede coincidir con una respuesta autonómica embotada, lo que constituye el subtipo disociativo del trastorno de estrés postraumático (TEPT). Objetivo: En esta revisión sistemática resumimos las investigaciones que evalúan la activación del sistema nervioso autónomo (por ejemplo, la frecuencia cardíaca, la presión arterial) y la disociación en pacientes con TEPT para discernir la validez de los modelos neurofisiológicos actuales de la hipoactivación relacionada con el trauma. Método: De 553 artículos seleccionados, se incluyeron en el análisis final 28 estudios (N=1300 sujetos) que investigaban la respuesta fisiológica a la provocación del estrés o a las intervenciones relacionadas con el trauma. Resultados: No existe una tendencia clara en todos los marcadores fisiológicos medidos en la disociación relacionada con el trauma. Los resultados extraídos son inconsistentes, en parte debido a la alta heterogeneidad en la metodología experimental. Conclusión: La presente revisión no puede aportar pruebas sólidas de que la disociación peri y postraumática esté asociada a la hipoactivación, lo que cuestiona la validez de los distintos perfiles psicofisiológicos en el TEPT 创伤相关解离和自主神经系统：一项对 PTSD 患者解离体验的心理生理相 关因素的系统文献综述 背景：神经生理学模型将解离(例如，在创伤事件期间或之后感到超然)与低唤起联系起 来。目前假设对威胁的初始被动反应可能与迟钝的自主反应同时发生，这构成了创伤后应 激障碍 (PTSD) 的解离亚型。 ARTICLE HISTORY