Cognitive and Emotional Factors in Visual Exploration Among Patients With Post-Traumatic Stress Disorder (SAILLANCE2)

Study Overview
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Brief Summary
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Post-traumatic stress disorder (PTSD) is characterized by hypervigilance. In particular, previous works suggest that patients tend to scan constantly the environment for possible threats. The present project aims at investigating such attentional bias in patients with PTSD using the change blindness paradigm that offers the interesting possibility of studying sensitivity to sudden changes using ecological stimuli. More precisely, the investigators will investigate whether patients are more sensitive than matched controls to sudden changes in the visual environment and whether this hypersensitivity is specific or even stronger when visual information has an emotional content. The attentional bias will be measured using motor responses (accuracy and speed to indicate the occurrence of a change by pressing a button) as well as eye movements.

Official Title
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Cognitive and Emotional Factors in Visual Exploration Among Patients With Post-Traumatic Stress Disorder

Conditions
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Post-Traumatic Stress Disorder

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: a diagnosis of PTSD based on the standard DSM-IV criteria, normal or corrected vision. clinically stable at the testing time Exclusion Criteria: history of neurological illness or trauma that occurred in the previous six months, - pregnant and nursing women, drugs use in the last 24 hours, an acute ocular disorder. Participants will not be under tutorship, curatorship or deprived of liberty.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Post-Traumatic Stress Disorders (PTSD)<br>30 patients with PTSD (diagnosis based on the standard DSM criteria) | |
| Controls<br>30 healthy controls without any psychiatric or neurological diagnosis | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Response time before the detection of neutral and emotional stimuli. | The explicit response of the participants will be measured with the response time before the detection of neutral and emotional stimuli. | Baseline: one session | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of correct detections compared with the missed detections and false alarms. | Performances will be measured by a sensitivity index (D prime) . This sensitivity index considers the number of correct detections compared with the missed detections and false alarms. | Baseline: one session | 
| Total duration until the participant first fixed on a ROI. | The implicit response will be measured by the localization and duration of fixations. All fixations outside the recording field will be excluded. The main variable will be the mean latency of the first fixation in a region of interest (ROI). This variable corresponds to the total duration until the participant first fixed on a ROI. | Baseline: one session | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Change blindness, Eye tracking, Implicit response