Confidence in Gambling Disorder: The role of dopamine, incentives and cognitive flexibility

Recruitment & Eligibility

Status: Pending

Sex: Not specified

Target Recruitment: 60

Inclusion Criteria

GD group:
1. DSM-5 diagnosis for Gambling Disorder (To ensure that we are including people who exhibit pathological gambling behaviour, also considered compulsive gambling, we decided to include people who actually received this diagnosis and will by definition exhibit abnormal behaviour).
2. No other psychiatric disorders
3. Willingness and ability to give written informed consent and willingness and ability to understand, to participate and to comply with the study requirements
4. 20-55 years of age
5. Male

HC group:
6. No current psychiatric diagnosis or history of addictions
7. Willingness and ability to give written informed consent and willingness and ability to understand, to participate and to comply with the study requirements
8. 20-55 years of age
9. Male

Exclusion Criteria

A potential subject who meets any of the following criteria will be excluded from participation in this study:
All groups:
1. Current major depressive disorder, bipolar disorder, psychotic disorder, alcohol or substance dependence, or any cognitive disorder as assessed with the MINI neurological disorders section
2. IQ below 80
3. Insufficient command of the Dutch language
4. MRI contraindications such as metal implants or claustrophobia
5. Use of dopaminergic ADHD medication,
6. Endocrinological disorders or regular use of corticosteroids
7. History of neurological treatment
8. History of epilepsy
9. History of autonomic failure
10. History of clinically significant hepatic, cardiac, obstructive respiratory, renal, cerebrovascular, metabolic or pulmonary disease
11. Claustrophobia
12. Use of other psychotropic medication, or of recreational drugs over a period of 72 hours prior to each test session, and use of alcohol within the last 24 hours before measurement
13. Irregular sleep/wake rhythms (e.g. regular nightshifts)
14. Use of MAO inhibitor, anaesthetic, anti-depressant or anti-psychotic drugs within the week prior to the start of the study
15. History of prescribed medication within the last month prior to the start of the study
Exclusion criteria directly related to PET scanning for both groups:
1. Participation in a scientific examination where radiation was used, in the last year
2. Positive urine drug screen on the day of the PET scan. Participants will be tested on cannabis, amphetamine, XTC, cocaine and opiates. Only recent cannabis use will be accepted
3. Lactose intolerance (entacapone and carbidopa capsules contain lactose)

Study & Design

Study Type: Observational non invasive

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Dopamine synthesis capacity (Ki values)

Secondary Outcome Measures

Name	Time	Method
Confidence levels in symptom-relevant context & Cognitive flexibility in reversal learning & nMRI signal & Gambling symptom severity

Related Trials