Posttraumatic stress disorder, or PTSD, is usually associated with flashbacks and nightmares after a frightening event. Some people with the condition also see or hear things that are not there or feel paranoid, symptoms that resemble psychosis and can lead to the wrong diagnosis. A new review of the evidence suggests these experiences are largely a product of trauma rather than a sign of a separate psychotic illness.
Researchers at Hodeidah University in Yemen, with colleagues at Universiti Utara Malaysia and Ain Shams University in Egypt, carried out a systematic review of 41 studies published between 2000 and 2024. The findings appear in The Open Psychology Journal. The review asked whether PTSD is best understood as a psychological condition or as one with psychotic features.
The team searched five research databases, including PubMed and PsycINFO. Of 442 records found, 41 studies met the criteria, ranging from brain scanning studies to clinical trials, and covering civilians, military personnel, and people in clinical care.
A systematic review gathers the research on a question using fixed rules about which studies count. Psychotic-like symptoms include hallucinations, false beliefs, paranoia, and distorted perceptions. Dissociation is a sense of being detached from one’s body, memories, or surroundings, and it is common after severe or repeated trauma.
Brain scans pointed to a pattern that differs from psychotic illness. About 78% of the relevant studies found a smaller hippocampus, a region involved in memory, and 65% found an overactive amygdala, which processes fear. Schizophrenia more often shows enlarged fluid-filled spaces in the brain and a thinner outer layer.
Psychotic-like symptoms were reported in 22% of PTSD cases in one study and in up to 40% of people with chronic trauma. They were most common after prolonged or early-life trauma, and greater trauma complexity went with more severe and dissociative symptoms. The overlap with psychotic disorders appeared partial and largely tied to trauma, rather than pointing to an underlying psychosis.
Psychological therapies outperformed medication over the long term. Trauma-focused cognitive behavioural therapy and eye movement desensitisation and reprocessing, known as EMDR, produced large effects. Antidepressants known as SSRIs helped about 60% of patients, but in one study 36.4% relapsed after stopping them, compared with 16.4% of those who carried on.
The authors argue for a trauma-spectrum model, which accepts some overlap with psychosis while keeping PTSD rooted in its psychological basis. Getting this right matters, because studies from US veterans’ services found antipsychotic drugs were often prescribed without a formal diagnosis to justify them.
The study has clear limits. The 41 studies varied in design, sample size, and diagnostic criteria, most were cross-sectional or correlational, and selective reporting may have shaped some results. The review was not registered in advance, and cultural differences in how trauma is understood were not consistently addressed.
The conclusions fit a wider move towards seeing trauma responses on a spectrum, reflected in the recognition of complex PTSD in the World Health Organization’s ICD-11 classification. Trauma-focused cognitive behavioural therapy and EMDR are already recommended treatments in clinical guidelines, including those from NICE in the UK.
Psychotic-like symptoms in PTSD mostly reflect severe trauma rather than psychosis, and talking therapies work best, a review suggests.
