Neural changes following cognitive behaviour therapy for psychosis: a longitudinal study

Area of Science:

• Neuroscience
• Psychiatry
• Clinical Psychology

Background:

• Persistent positive symptoms, especially delusions, are a core feature of schizophrenia.
• Cognitive Behaviour Therapy for Psychosis (CBTp) shows promise in improving these symptoms.
• Threat perception and processing are implicated in the development of delusions.

Purpose of the Study:

• To investigate functional brain changes associated with CBTp in schizophrenia patients.
• To explore how CBTp affects neural responses to threatening stimuli.
• To correlate brain changes with clinical symptom improvement.

Main Methods:

• A randomized controlled trial involving 56 schizophrenia outpatients with persistent positive symptoms.
• Participants received either CBTp plus treatment-as-usual (TAU) or TAU alone for 6-8 months.
• Functional magnetic resonance imaging (fMRI) assessed brain activity during an affect processing task at baseline and follow-up.

Main Results:

• The CBTp+TAU group demonstrated significant clinical improvement, unlike the TAU-only group.
• fMRI revealed decreased activation in the inferior frontal, insula, thalamus, putamen, and occipital areas in the CBTp+TAU group in response to fearful and angry expressions.
• Reduced fMRI response to angry expressions correlated directly with symptom improvement.

Conclusions:

• CBTp attenuates neural responses to threatening stimuli in schizophrenia patients.
• Symptom reduction may be mediated by a less distressing processing of threats.
• This study provides neurobiological evidence for the efficacy of CBTp in treating positive symptoms of schizophrenia.