Biomarkers of Online Gambling Addiction

Internet gaming is a major risk for the vulnerable in terms of risk of dependence, emergence of psychiatric disorders, financial consequences, and family. Addictions to games in France represent 1 to 2% of the general population. Online poker happens to be a specific form of gambling which has the fastest growing online games. If vulnerabilities factors have been reported in many studies, to date no biomarkers for screening people at risk are available.

One of the favorite way in biomarker research concern impaired decision-making capacity biomarkers. In a previous work, investigators have shown that the decision was strongly linked to motivation and impaired decision-making capacity would be associated with a motivational dys-regulation (Giustiniani et al., 2015) .

The search for biomarkers in parallel to the motivation of the decision making is essential and yet this day nonexistent in the literature. Here, with subjects addicted to online poker, a behavioral protocol developed to measure motivation in pathological populations (Effort-Expenditure for Rewards Task, EEfRT) will be used and will be specifically adapted to be studied by functional neuroimaging.

The main objective is to identify alterations of motivational processes related to decision making in conditions of uncertainty associated with gambling addiction. For this purpose, the dynamics between brain systems involved in decision making and motivation will be studied.

As a secondary objective, correlations between neural activity and performance to different tests used to measure decision making (Iowa Gambling Task IGT) and motivation (EEfRT) will be evaluated. Finally the influence of motivation level on the performance score to decision making task will be evaluated, the goal will be the development of an optimal strategy in terms of prevention.

The study will be conducted at the University Hospital of Besancon during 36 months with 73 participants:

The experiment will involve three stages:

• stage 1 : validation of HR-EEG adaptated motivation EEfRT task adaptated to HR-EEG by 20 healthy volunteers .
• stage 2: identification of biomarkers by 20 addict online poker gamblers and 20 non-addict online poker gamblers
• stage 3 : validation of previously identified biomarkers by 13 online poker gamblers recruted in poker forum.

All stages progress according to the same plan:

• Standardized questionnaire to define the socio-demographic data, the diagnosis of gambling addiction (ICJE criteria (Indice Canadien fu Jeu Excessif), screening for comorbidities addictive, the level of anxiety and impulsivity.
• Registration of brain activity (randomisation): during the performance of a task of motivation evaluation laboratory (EEfRT) adaptated for high-resolution electroencephalography AND during a laboratory task that assesses decision making in conditions of uncertainty (IGT) with its version for high-resolution electroencephalography has already been validated in a previous study (Giustiniani et al., 2015).

Statistical analysis will aim to compare the average activation differences between the two populations for each functional neuroimaging examination. Then a subject-by-subject analysis of each brain activation will be conducted to look for correlations between the various examinations and strength of neuronal response.

Following this study, the results will allow us to identify biomarkers of addiction that will help improving vulnerable populations screening capabilities to tailor prevention strategies. Furthermore the identification of specific neural correlates dependence will adapt therapeutic strategies.