A narrative review of psychological theories of post-traumatic stress disorder, voice hearing, and other psychotic symptoms

Background: Most voice hearers report childhood trauma. Many voice hearers report comorbid post-traumatic stress symptoms and that the content of their voices (auditory verbal hallucinations) is directly (voices repeat phrases spoken by perpetrators) or indirectly (voice content and trauma is thematically similar) related to their trauma. The factors that maintain trauma-related voices are unknown, and there is limited research in this area. This study aimed to identify potential maintaining factors of trauma-related voices by reviewing models of post-traumatic stress disorder (PTSD) and positive symptoms of psychosis. Method: Models of PTSD and positive symptoms were reviewed to identify potential factors that are unique and common to both sets of symptoms. Results: We reviewed 10 models of PTSD, 4 models of positive symptoms, and 2 trauma-informed models of voice hearing. One model provided a theoretical explanation of different types of trauma-related voices. Twenty-one factors were extracted from 16 theoretical models. No existing model incorporated all these factors. Discussion: Existing PTSD and positive symptom models present a range of common and unique factors. There may be value in extending existing integrative models to include a broader range of potential factors that could explain different pathways to, and expressions of, trauma-related voices. A future research agenda is presented to investigate how such an extension could lead to more complete individualized case formulations and targeted treatments.