Clinical trial NCT03188133: Visual Information Processing in Schizophrenia Patients With Visual Hallucinations
Official title: Top Down Visual Information Processing in Schizophrenia Patients With Visual Hallucinations
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Schizophrenia
Visual Hallucination
Auditory Hallucination
False Perception
Keywords: Schizophrenia
Visual Hallucination
False Perception
emotional priming
Lead sponsor: Central Hospital, Nancy, France
Sponsor class: OTHER
First posted: 2017-06-15
Enrollment: 90
Sex: ALL
Minimum age (years): 18
Maximum age (years): 55
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: Occurrence of visual hallucinations (VHs) in schizophrenia depend in part on disorders in the processing of late visual information (Top-Down). The broader question of how these top-down mechanisms (cognitive and / or emotional mechanisms) are involved in the occurrence of VHs remains to be specified and very few behavioral studies have so far been interested. The investigators propose to study the implication of Top-Down mechanisms in the visual hallucinatory manifestations, more specifically in the processing of ambiguous stimuli during an emotional priming task. Schizophrenia patients with VHs would have more false visual perceptions in the treatment of ambiguous stimuli than schizophrenia patients with auditory hallucinations or no hallucinations (AH/NH) and healthy controls.

Detailed description: In schizophrenia patients with auditory hallucinations, top-down mechanism on perceptual processing could be illustrated by tasks of listening to white noise. These studies show that psychotic subjects detect more words and phrases when exposed to these stimuli. In schizophrenia patients with VHs, to our knowledge no study have explored the mechanism of false perception. Thus, we propose to experimentally manipulate the implication of Top-Down mechanisms on visual perception using an emotional priming task. This paradigm has already been used in this population to explain the mechanisms underlying productive symptoms. For example, in an emotional priming task authors have shown that a negative valence primer contributes to the implementation of an interpretive bias in a confidence judgment task.

The aim of the present study is to explore the implication of these Top-Down mechanisms in hallucinatory manifestations, more specifically on the treatment of ambiguous visual stimuli during an emotional priming task by manipulating the emotional valence of the primer. The goal is to determine how emotional environmental elements contribute to the formation of erroneous perceptions in patients with schizophrenia with VHs.

Eligibility criteria: All Groups:

* Age between 18 and 55 years
* Affiliation to or benefiting from a social security
* Visual acuity normal or corrected to normal
* Person who received and understood the complete information about the organization of the research and gave written and free informed consent before participating in the study

Group of patients with schizophrenia with visual hallucination (HV) with or without auditory hallucination (HA) (HV group):

* Schizophrenia according to the Diagnostic and Statistical Manual of Mental Disorders IV criteria
* Presence of a hallucinatory visual symptomatology (HV) in the history of the disease measured by the Psychosensory hallucination scale (PSAS).
* The presence of a hallucinatory symptomatology in auditory mode (HA) in addition to the HV is not a criterion of non-inclusion.

Group of patients with schizophrenia either with auditory hallucination (HA) but without visual hallucination (HV) or no hallucination, auditory or visual (NH) (HA / NH group)

* Schizophrenia according to the Diagnostic and Statistical Manual of Mental Disorders IV criteria
* Presence of a hallucinatory symptomatology in auditory mode (HA) in the history of the disease measured by the PSAS or absence of any hallucinatory manifestations in the history of the disease
* Absence of visual hallucinatory symptomatology (HV) in the history of the disease as measured by PSAS

Primary outcomes:
measure: Number of false visual perception on the emotional priming task
timeFrame: through study completion an average of 6 months
Secondary outcomes:
measure: number of false visual perception on the emotional priming task depending of the emotional valence manipulated
timeFrame: through study completion an average of 6 months
measure: Cognitive performances at the neuropsychological assessment
timeFrame: through study completion an average of 6 months
measure: Psychosensory hallucinations scale scores
timeFrame: through study completion an average of 6 months
Other outcomes:
Locations:
Study officials:
affiliation: Central hospital Nancy, Centre Psychothérapique de Nancy
name: Vincent LAPREVOTE
role: PRINCIPAL_INVESTIGATOR
References:
citation: Catalan A, Simons CJ, Bustamante S, Drukker M, Madrazo A, de Artaza MG, Gorostiza I, van Os J, Gonzalez-Torres MA. Novel evidence that attributing affectively salient signal to random noise is associated with psychosis. PLoS One. 2014 Jul 14;9(7):e102520. doi: 10.1371/journal.pone.0102520. eCollection 2014.
citation: Hoffman RE, Woods SW, Hawkins KA, Pittman B, Tohen M, Preda A, Breier A, Glist J, Addington J, Perkins DO, McGlashan TH. Extracting spurious messages from noise and risk of schizophrenia-spectrum disorders in a prodromal population. Br J Psychiatry. 2007 Oct;191:355-6. doi: 10.1192/bjp.bp.106.031195.
citation: Galdos M, Simons C, Fernandez-Rivas A, Wichers M, Peralta C, Lataster T, Amer G, Myin-Germeys I, Allardyce J, Gonzalez-Torres MA, van Os J. Affectively salient meaning in random noise: a task sensitive to psychosis liability. Schizophr Bull. 2011 Nov;37(6):1179-86. doi: 10.1093/schbul/sbq029. Epub 2010 Apr 1.
citation: Hooker CI, Tully LM, Verosky SC, Fisher M, Holland C, Vinogradov S. Can I trust you? Negative affective priming influences social judgments in schizophrenia. J Abnorm Psychol. 2011 Feb;120(1):98-107. doi: 10.1037/a0020630.