Schema therapy (ST) is an integrative psychotherapy approach developed by Young with a primary focus on treating borderline personality disorder (BPD). There are two theoretical models in ST: early maladaptive schemas (EMS) and schema modes. EMS are those formed in the early stages of life that are initially appropriate but interfere with the individual's ability to conduct daily life. In the study by Young, 18 different EMS were identified. Meanwhile, the model of schema modes has four categories: 1) child mode, 2) maladaptive coping mode, 3) dysfunctional parent mode, and 4)healthy adult mode. Each mode refers to an individual's current state at any given point in time when the schema is activated. ST aims to encourage the patient to reflect on their life history and understand the types of EMS they possess. It employs various techniques which release the patient from these EMS while healing their "vulnerable child" mode and strengthening their "healthy adult" mode. ST particularly emphasizes the "limited reparenting" in which the therapist cares for the client and offers corrective emotional experiences. Evidence for ST in treating BPD has been confirmed in several randomized controlled trials (RCT). However, its application to complex post-traumatic stress disorder (C-PTSD), a disorder that has newly been listed in the ICD-11, merits further examination. According to Herman, who originally proposed the diagnosis, C-PTSD significantly overlaps with BPD. Trauma is included in the theoretical model of EMS, which are formed through traumatic experiences in early life. ST techniques encompass interventions for trauma. Furthermore, the model of schema modes effectively explains symptoms of C-PTSD such as negative self-concept, emotion dysregulation, and dissociation, which provides direction for intervention. These overlaps suggest that ST is a promising treatment method for C-PTSD, and future clinical research can be expected. This paper discusses the potential of ST for application to C-PTSD treatment and presents a case example.
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