REALITY MONITORING AND DOPAMINE
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Précurseur de la dopamine, antagoniste D2, PLACEBO.
- Who it may be relevant to
- Registry conditions: Neurosciences. Basic parameters: 18 years — 45 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- France
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Official title
The Role of Dopamine in Reality Memory
Overview
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.
Detailed description
This hypothesis is based on several studies in the literature: 1) DA transmission anomalies are observed in both schizophrenia and Parkinson's disease; 2) DA agonists may induce hallucination; 3) DA antagonists reduce hallucinations and improve reality-monitoring abilities in patients with schizophrenia. In addition, also suggesting a link between mesocorticolimbic connectivity, subcortical DA transmission and reality-monitoring, The investigators have shown that fronto-temporal transcranial Direct Current Stimulation (tDCS) leads:
* on the one hand, to modulate reality-monitoring performance in healthy volunteers and patients; * on the other hand, to induce subcortical DA release. However, to date, no study has yet explored the direct link between DA transmission and reality-monitoring.
Interventions
- Other Précurseur de la dopamine
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 - Other antagoniste D2
In the second condition, volunteers will receive Sulpiride 800 mg - Other PLACEBO
In the third condition, volunteers will receive placebo
Primary outcome measures
- Reality-monitoring performance [Time frame: One month]
Secondary outcome measures (2)
- Reaction times at the reality-monitoring task and scores of subjective confidence rating for reality-monitoring responses [Time frame: One month]
- Other cognitive tasks [Time frame: One month]
Eligibility criteria
Inclusion criteria
- 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
Exclusion criteria
- 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
- Cardiologic or severe medical conditio
- Pregnancy(checked with a pregnancy autotest), lactation, or insufficient contraceptive measure (precautionary measure)
- Consumption of recreational drugs during the last 6 months
- Known sensitivity to any of the study medication and their excipients
- Lactose intolerance
- Porphyria
- Hepatic insufficiency
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- Randomized
- Model
- Crossover
- Masking
- Single blind
- Primary purpose
- Basic science
Study locations
France · 1 center
- Centre Hospitalier le Vinatier — Bron
Identifiers
NCT: NCT05711082 · 2022-A01345-38