Using Illusions to Boost Social Cognition

This study is a randomized, controlled, monocentric trial evaluating a novel sensory-motor rehabilitation approach for social cognition. The study is based on the hypothesis that perception is interpretative and viewpoint-dependent, and that realizing this through concrete experience could generalize to higher-level cognitive processes required for social understanding.

Participants will attend three visits and complete questionnaires and tasks that assess social understanding before and after the activity, and again one month later.

Two groups will take part: one completing the workshop shortly after inclusion, and one completing it after a delay, allowing comparison over time. Participants will be randomized in one condition.

This research does not involve medication. It consists of simple tasks such as observing and describing visual stimuli, followed by a facilitated discussion.

Neuropsychological tests and questionnaires will be used to measure changes over time.

Expected impact: By inducing concrete perspective-shifts, the intervention aims to improve mentalizing, reduce egocentric biases, and strengthen interpretation of social cues. This bottom-up sensory-motor approach may overcome limitations of classical cognitive remediation programs by promoting deep experiential learning rather than top-down instruction.

If effective, the method may support long-term social reintegration, psychosocial functioning, and inspire wider clinical applications due to its low cost, ease of deployment, and strong ecological engagement.

Inclusion criteria

• Aged 18 to 40 years
• Fluent French speaker
• Has provided written informed consent
• For individuals under guardianship (curatorship): inclusion is permitted if the curator is available to assist or advise when needed.
• Established diagnosis of schizophrenia, schizoaffective disorder, schizophreniform disorder, or brief psychotic disorder according to theDiagnostic and statistical manual of mental disorders (DSM-5-TR) criteria
• Presence of social cognition impairment, defined by:subjective complaint reported by the participant or identified by care teams regarding difficulties in social interaction and clinical confirmation of observable difficulties (e.g., social withdrawal, misinterpretation of others' intentions, inappropriate social behaviour)
• Membership or entitlement to a social security plan

Exclusion criteria

• Clinical state incompatible with participation in group-based activities (e.g., severe psychomotor agitation, severe behavioural disturbance)
• Concurrent participation in another social cognition remediation program
• Diagnosis of intellectual disability
• Insufficient comprehension of French for verbal interaction and test completion
• Significant change in psychotropic medication within the past month
• Uncorrectable visual impairment preventing participation
• Pregnant women
• Individuals under full guardianship (tutorship)