Hallucinations across sensory domains in people with post-traumatic stress disorder and psychosis

Auditory hallucinations are common in people with histories of adversity, possibly indicating a causal relationship. However, hallucinations occur in multiple sensory modalities and the relationship between trauma and hallucinations in other sensory domains is less explored. We examined the occurrence of hallucinatory experiences in different sensory modalities in people with psychosis who also met criteria for Post-Traumatic Stress Disorder (n = 67). Particular attention was paid to the number of modalities reported and whether the experiences were linked to the person's adversity. This linkage was explored in two ways. First, it was predicted that those people reporting more trauma experiences and symptoms of PTSD would report a greater number of hallucination modalities. Second, we examined if there was content or thematic linkage between the trauma and the hallucinatory experiences. There were high levels of reported auditory (89.6 %), visual (58.2 %) and tactile (46.3 %) hallucinations. Hallucinations in two or more modalities were the norm (71.6 % of the participants). The number of hallucination modalities was moderately associated with a greater number of past traumas and PTSD symptoms. There was a high degree of content and thematic linkage between the trauma and the hallucinations. The linkage between trauma and auditory hallucinations extends to other sensory domains.