Neural Correlates of Social Touch and Interoceptive Perception as Potential Biomarker for Impaired Social Functioning

Study Overview
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Brief Summary
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Recent studies have shown that certain biomarkers of schizophrenia could help to better assess the individual course of the disease and thus, contribute to more personalized treatment options. The aim of the SPIRIT study is to identify potential biomarkers for the prediction of disease-associated outcomes by investigating the neurobiological mechanisms of underlying schizophrenia-related dysfunctions.

Detailed Description
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Alterations in psychosocial functioning are evident from the prodromal phase of schizophrenia and play a crucial role in its chronic course. While recent studies have demonstrated the predictive validity of structural changes in the brain anatomy of patients with schizophrenia, there is a lack of studies assessing the predictive value of disease-associated alterations in the functional brain activity for symptom severity and psychosocial functioning in schizophrenia. In this longitudinal, observational study, 60 patients with schizophrenia and 40 healthy subjects without family history of psychotic illness will be recruited to investigate differences in behavioural, physiological, and neural correlates of social touch and interoceptive perception between participant groups. Participants' symptom severity and psychosocial functioning level will be examined by a wide range of behavioural, physiological, and neural methods. Potential biomarkers will be identified by estimating the predictive value of initially performed methods on follow-up re-examination of clinical and psychosocial outcomes. Neural readouts include structural and functional magnetic resonance imaging (fMRI) measurements. The fMRI tasks will probe the processing of social touch and interoceptive perception; additionally resting-state connectivity will be assessed. To further investigate pathological distortions of social touch and interoceptive perception, bodily touch allowance maps will be measured and participants will perform a heart-beat discrimination task. Psychometric questionnaires and semi-structured interviews will be used to capture symptom load and level of psychosocial functioning. Long-term effects will be assessed by online questionnaires and semi-structured interviews via phone call 3- and 6 months after initial assessments. The investigators hypothesize that differences in the neural response to social touch as well as in the neural patterns of interoceptive perception could serve as potential biomarkers for psychosocial deficits during the course of the illness. Furthermore, the inclusion of those biomarkers in predictive models could improve the prediction of disease progression and thus, contribute to personalized therapy.

Official Title
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Neural Correlates of Social Touch and Interoceptive Perception as Potential Biomarker for Impaired Social Functioning

Conditions
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Schizophrenia

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participant is able to provide consent. Diagnosis of schizophrenia or schizoaffective disorder according to DSM-V Control group: No psychiatric or neurological illness. Fluent in German. Exclusion Criteria: The participant does not fulfill requirements for MRI measurements according to safety guidelines. Acute suicidality. Current substance dependence. A history of head trauma or neurological illness.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patient Group<br>Patients with Schizophrenia | |
| Control Group<br>Healthy subjects without family history of psychotic illness | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Neural responses in a social touch task | Participants will be measured with functional magnetic resonance imaging (fMRI) while they perceive different types of social and non-social touch | One-time baseline assessment | 
| Behavioral responses in a social touch fMRI task | Measured as behavioral ratings during the social touch fMRI task. During the social touch fMRI task, participants rate the comfort of the tactile stimuli on a visual analogue scale. | One-time baseline assessment | 
| Neural responses in an interoception fMRI task | Participants will be measured with functional magnetic resonance imaging (fMRI) while they perform an interoception task | One-time baseline assessment | 
| Behavioral responses in an interoception fMRI task | Measured by performance on the interoception task. During the interoception fMRI task, participants rate how intensely they perceived their heartbeat or their stomach on a visual analogue scale. | One-time baseline assessment | 
| Changes in clinician-rated symptom severity between baseline and follow-ups | Measured by half-structured interviews (e.g. Positive and Negative Syndrome Scale (PANSS); range: 30-210; higher scores indicating more severe symptoms) for disease-related symptoms | Baseline, 3 and 6 months follow- up after initial baseline assessment | 
| Changes in self-reported symptom severity between baseline and follow-ups | Measured by self-evaluation questionnaires (e.g. Self-assessment of Negative Symptoms (SNS); range 1-20; higher scores indicating more severe symptoms) for disease-related symptoms | Baseline, 3 and 6 months follow- up after initial baseline assessment | 
| Changes in clinician-rated social-role functioning between baseline and follow-ups | Measured by the clinician-rated the social-role functioning scale (range: 1-10; higher scores indicating higher functioning) | Baseline, 3 and 6 months follow- up after initial baseline assessment | 
| Changes in self-reported social-role functioning levels between baseline and follow-ups | Measured by the self-evaluation questionnaires for social-role functioning (e.g. Social Network Index (SNI); range 1-12; higher scores indicating higher functioning) | Baseline, 3 and 6 months follow-up after initial baseline assessment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bodily maps of social touch | Measured as performance on a bodily maps computer task | One-time baseline assessment | 
| Attitude towards social touch | Measured by the self-evaluation questionnaire for social touch tolerance (e.g. Social Touch Questionnaire; range 0-4; higher scores indicating higher touch tolerance) | One-time baseline assessment | 
| Interoceptive accuracy | Measured as performance on a heartbeat discrimination task | One-time baseline assessment | 
| Interoceptive awareness | Measured by a self-evaluation questionnaire for interoceptive awareness (e.g. Multidimensional Assessment of Interoceptive Awareness (MAIA); range 0-5; higher scores indicating higher interoceptive awareness) | One-time baseline assessment | 
| Blood parameter | Measured by schizophrenia related, Nuclear Magnetic Resonance spectroscopy (NMR) based metabolomics | One-time baseline assessment | 
| Urine parameter | Measured by schizophrenia related, Nuclear Magnetic Resonance spectroscopy (NMR) based metabolomics | One-time baseline assessment | 
| Neural activity at resting state | fMRI will be performed to measure BOLD-signal while participants lay in the MRI-scanner with eyes open. | One-time baseline assessment | 
| Structural connectivity measure | fMRI will be performed to measure BOLD-signal while participants lay in the MRI-scanner with eyes open. | One-time baseline assessment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Biomarker-based prediction, Precision Psychiatry, Schizophrenia, Social functioning, Social Touch, Interoception, fMRI