REALITY MONITORING

NCT05711082 | Recruiting DMC

• 1 other identifier: 2022-A01345-38
• Study Type: interventional
• Target: 39
• Locations: 1 country
• Sites: 1

Brief Summary

Reality-monitoring characterizes the ability to determine whether information was perceived in the environment or only imagined . Impaired reality-monitoring abilities have been associated with hallucinations in patients with schizophrenia and patients with Parkinson's disease. The investigators hypothesize a link between dopaminergic (DA) transmission and reality-monitoring.

Conditions

Neurosciences

Outcome Measures

Primary Outcomes (1)

• Reality-monitoring performance

  Measured with a behavioral task developed, validated and used in investigators lab. During the memory retrieval phase, 48 words will be presented, including the 32 words presented during encoding as well as 16 new words. Subjects will be required to identify whether each word was previously heard, imagined or new. Three words lists will be used and assigned randomly depending on the substance condition (L-dopa, Sulpiride, placebo). Each verbal list will include 16 items with the "imagine hear" encoding condition and 16 items with the "listen" encoding condition. A single measure including two variables of interest will account for the main evaluation criteria: * The average conditional source-identification measure (ACSIM) which represents the overall ability to correctly retrieve the source, conditional on that item was recognized as already presented. * The source misattributions,the number of confusions between heard and imagined events.

  One month

Secondary Outcomes (2)

• Reaction times at the reality-monitoring task and scores of subjective confidence rating for reality-monitoring responses

  One month

• Other cognitive tasks

  One month

Study Arms (3)

Dopamine precursor

ACTIVE COMPARATOR

In the first condition, volunteers will receive a dopamine (DA) precursor (L-dopa, 100mg). L-dopa will be combined with a dose of an Aromatic amino acid decarboxylase inhibitor (Benserazide) 25mg to multiplicate its bioavailability and with a dose of domperidone 10mg (peripheral antagonist of DA) to minimize the risk of side effects.

Other: Précurseur de la dopamine

D2 antagonist

ACTIVE COMPARATOR

In the second condition, volunteers will receive a D2 antagonist (Sulpiride, 800mg)

Other: antagoniste D2

PLACEBO

PLACEBO COMPARATOR

In the third condition, volunteers will receive a placebo (lactose)

Other: PLACEBO

Interventions

Précurseur de la dopamine OTHER

In the first condition, volunteers will receive a 100mg dose of L-dopa, 25mg dose of Aromatic amino acid decarboxylase inhibitors (Benserazide) and 10mg dose of Domperidone. In the second condition, volunteers will receive Sulpiride 800mg. In the third condition, volunteers will receive placebo Reality-monitoring performances will be evaluated with a standardized task. Working-memory will be evaluated with the n-back task. Self-monitoring performances will be observed during a speech production experiment in which speakers monitor their auditory feedback while speaking. Speech Bayesian reasoning: This task is a home-made task investigating the influence of prior on speech processing. Subjects will be required to identify speech in ambiguous auditory stimuli. Visual Bayesian reasoning: This task investigates the influence of prior on visual processing. Subjects will be required to recognize morph between faces and house.

Dopamine precursor

antagoniste D2 OTHER

In the second condition, volunteers will receive Sulpiride 800 mg

D2 antagonist

PLACEBO OTHER

In the third condition, volunteers will receive placebo

PLACEBO

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy volunteers who have given their written informed consent
• Men and women from 18 to 45 years old
• Normal or corrected vision
• Being fluent in French or French for native language
• Being affiliated with health insurance

You may not qualify if:

• Healthy volunteers who have given their written informed consent
• Men and women from 18 to 45 years old
• Normal or corrected vision
• Being fluent in French or French for native language
• Being affiliated with health insurance
• Inadmissibility of the subject's consent or refusal
• Working-memory deficit (as controlled with MMSE score\< 23)
• Any past or current psychiatric or somatic condition(as controlled with the Mini International Neuropsychiatric Interview, MINI)
• Any past or current neurological condition
• History of cranio-cerebral trauma, arterial hypotension or hypertension, cardiological or serious medical condition
• Abnormal potassium dosage (below 3.1 mmol/L or above 4.9 mmol/L)
• Anormal ECG
• History of schizophrenia or bipolar disorder in first-degree relatives
• Alcohol-drinking and caffeine intake at least during 24 hours before each session
• Drug therapy excepting contraceptives

Sponsors & Collaborators

• Hôpital le Vinatier: lead

Study Sites (1)

Centre Hospitalier le Vinatier

Bron, 69678, France

RECRUITING

Study Officials

• FILIPE GALVAO

  Centre Hospitalier le Vinatier

  PRINCIPAL INVESTIGATOR

Central Study Contacts

JEROME BRUNELIN

CONTACT

0033437915565; jerome.brunelin@ch-le-vinatier.fr

VERONIQUE VIAL

CONTACT

0033437915522; veronique.vial@ch-le-vinatier.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: double dummy, placebo-controlled
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: MORDOR study will use a randomized, double dummy, placebo-controlled, three-arm crossover design.

Study Record Dates

• First Submitted: January 23, 2023
• First Posted: February 2, 2023
• Study Start: January 15, 2024
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: March 6, 2025

Record last verified: 2025-02

Data Sharing

• IPD Sharing: Will not share

Locations

FR (1)