Researchers conducted a large review to test a theory about psychosis. The theory suggests that people with conditions like schizophrenia might process sensory information differently by relying too much or too little on their past expectations. The analysis combined data from many previous studies, involving 904 adults with schizophrenia-spectrum psychosis and 1,039 healthy adults for comparison. They looked at how people used their expectations during various perception tasks.
The main finding was that, overall, there was no evidence that people with psychosis used their prior expectations in an unusual way compared to healthy individuals. The analysis also specifically checked if this was connected to two major symptoms: delusions and hallucinations. It found no clear link between how someone used expectations and whether they experienced these symptoms.
This was a meta-analysis, which means it combined results from many smaller observational studies. This type of research can identify patterns but cannot prove that one thing causes another. The authors note their findings do not support the idea that psychosis involves a broad, general problem with how the brain predicts and processes sensory information across different situations.
For readers, this research helps refine scientific theories about how the brain works in psychosis. It suggests that if there are differences in how expectations guide perception, they might be more specific or complex than a simple overall shift. The results are important for guiding future, more detailed research rather than for immediate changes in understanding or treatment.