Using Illusions to Boost Social Cognition (SOLLUSIONS)

Socio-cognitive Benefits of Exposure to Visual Illusions in Patients With Psychotic Disorders

This study aims to explore whether the observation of complex visual objects can help improve social cognition in people living with psychotic disorders. Social cognition refers to the ability to understand what others think, feel, or intend, and plays a key role in social relationships and daily interactions.

Main questions this study aims to answer:

• Does dyadic exposure to complex visual objects improve mental state attribution, as measured by the Faux Pas Test?
• Does the intervention enhance related domains of social cognition, including implicit intention inference (Hinting Task), interpretation of complex interactions (Movie for the Assessment of Social Cognition, MASC), and reduction of hostile attribution biases (Ambiguous Intentions Hostility Questionnaire, AIHQ)?
• Are improvements maintained after one month, and do patients who receive the intervention later (waitlist group) show the same benefits once exposed?

Study Overview

• Status: Not yet recruiting
• Conditions: Social Cognition; Schizophrenia Spectrum Disorders
• Intervention / Treatment: Behavioral: Visual-illusion social cognition session (immediate); Behavioral: Visual-illusion social cognition session (delayed)

Detailed Description

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.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Joy El KHOURY; Phone Number: +330437915534; Email: joy.el-khoury@inserm.fr
• Study Contact Backup: Name: Méline Devaluez, PhD; Email: meline.devaluez@ch-le-vinatier.fr

Study Locations

• France
  • Bron, France, 69678
    • CH Le Vinatier
    • Principal Investigator: Frédéric HAESEBAERT, MD, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

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)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Immediate intervention; Participants receive the visual-perception session shortly after baseline assessment. They complete neurocognitive and social cognition tests before exposure, immediately after, and again at one-month follow-up.	Behavioral: Visual-illusion social cognition session (immediate); A guided session of approximately 45 minutes. The core rehabilitation tool consists of multiple-perspective illusion boxes. Each participant stands on one side of the box and perceives a different shape than their partner. The session unfolds in 3 structured phases: For each illusion : Participants observe objects silently and draw what they see.; Perspective confrontation + Card selection: Drawings and interpretation cards are exchanged and discussed.; Perspective switching : Participants swap positions to reveal the alternative visual interpretation. The session is followed by a short structured discussion with a psychologist focused on perspective-taking and interpretation of social cues.
Active Comparator: Delayed Intervention (Wait-list Control); Participants complete the same assessments as Arm 1 but receive the intervention only after a waiting period. This arm allows comparison between natural progression and workshop effects prior to exposure.	Behavioral: Visual-illusion social cognition session (delayed); A guided session of approximately 45 minutes. The core rehabilitation tool consists of multiple-perspective illusion boxes. Each participant stands on one side of the box and perceives a different shape than their partner. The session unfolds in 3 structured phases: 1. For each illusion : Participants observe objects silently and draw what they see. 2. Perspective confrontation + Card selection: Drawings and interpretation cards are exchanged and discussed. 3. Perspective switching : Participants swap positions to reveal the alternative visual interpretation. The session is followed by a short structured discussion with a psychologist focused on perspective-taking and interpretation of social cues. Delivered after a delay following baseline assessment.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
"Faux Pas" test total score	Total of correctly recognised "Faux Pas" Score range : 0 - 30 Minimum (0) : no correct detection of faux pas Maximum (30) : all faux pas correctly detected; Total of identified absence of "Faux Pas" Score range : 0 - 10 Minimum (0) : incorrectly identifies absence of faux pas Maximum (10) : correctly identifies absence of faux pas; Total score of control question comprehension Score range : 0 - 20 Minimum (0) : poor comprehension Maximum (20) : Full comprehension	Change from pre to post intervention (up to 3 hours)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hinting Task	Number of correctly inferred items with hint 1 Score range : 0 - 20 Minimum (0) : No correct inference of intentions Maximum (20) : All intentions correctly inferred; Number of correctly inferred items with hint 2 Score range : 0 - 20 Minimum (0) : No correct inference of intentions Maximum (20) : All intentions correctly inferred	Change from pre to post intervention (up to 3 hours)
MASC performance	Number of correct responses Score range 0 - 45 Minimum (0) : No correct mental state inference Maximum (45) : All mental states correctly inferred	Change from pre intervention to follow-up session (up to a month and a half)

Collaborators and Investigators

• Sponsor: Hôpital le Vinatier
• Collaborators: INSERM 1028

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): January 1, 2029
• Study Completion (Estimated): February 1, 2029

Study Registration Dates

• First Submitted: May 12, 2026
• First Submitted That Met QC Criteria: May 19, 2026
• First Posted (Actual): May 22, 2026

Study Record Updates

• Last Update Posted (Actual): May 22, 2026
• Last Update Submitted That Met QC Criteria: May 19, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Schizophrenia; Psychosis; Cognitive Remediation; Social Cognition; Metacognition; Theory of Mind; Social Interaction; Hinting Task; Mentalizing; Perspective-Taking; Visual Illusions; Viewpoint Illusions; Bottom-Up Intervention; Sensorimotor Rehabilitation; Faux Pas Test; Rehabilitation in Psychosis
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Schizophrenia Spectrum and Other Psychotic Disorders; Mental Disorders; Neurobehavioral Manifestations; Perceptual Disorders; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Schizophrenia; Psychotic Disorders; Illusions
• Other Study ID Numbers: 2025-A02057-42

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Anonymized IPD that underlie results in a publication may be shared upon reasonable scientific request following publication of study results.
• IPD Sharing Time Frame: IPD available after publication of primary results
• IPD Sharing Access Criteria: Requests must be made by qualified researchers for scientific purposes. Data will be shared under controlled access agreement ensuring privacy and ethical standards.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No