Evaluation of the Effect of tDCS on Cannabis Craving (TCC)

Evaluation of the Effect of tDCS on Cannabis Craving: Multicentre Randomized, Double-blind Study Versus Placebo

Cannabis is the most frequently consumed drug in France and its use continues to increase. Over the 18-64 age group as a whole, experimentation with cannabis at least once in a lifetime increased from 33% in 2010 to 42% in 2014, confirming the upward trend observed since the 1990. Cannabis, like all drugs, disrupts the reward circuit whose neurons originate in the ventral tegmental area and project into the mesolimbic and cortical structures. Acute cannabis use is thought to increase mesolimbic dopamine by affecting the Gabaergic or Glutamatergic system. Chronic cannabis use usurps the reward system and leads to changes in the mesolimbic circuit (nucleus accumbens, ventral tegmental area, amygdala, and prefrontal cortex), inducing increased craving, with persistent craving for the substance and vulnerability to relapse. Cognitively, addiction is associated with increased impulsivity, with a propensity to take risks leading to impaired decision-making. There is currently no validated drug treatment for cannabis addiction. Non-invasive brain stimulation could be an interesting therapeutic alternative.

The tDCS is a device for modulating cortical excitability. It consists of passing a low intensity direct electrical current over the scalp via two electrodes: an anode and a cathode soaked in a saline solution. Although there is a short-circuit effect through the scalp, a significant amount of electrical current enters the brain and changes the transmembrane potential.

The change to cannabis craving assessed by the Baseline Marijuana Craving Test at the end of treatment

The change in cannabis craving during an incentive to use task evaluated by analog visual scale scores (0 to 10)

assessment of the change in attention and inhibition skills as assessed by the Stroop test before and after a neurofeedback test

Inclusion Criteria: Men or women between 18 and 65 years of age Right-Handers Diagnosis: Cannabis Use Disorder (according to DSM 5 criteria) Patient with no other drug or psychotherapeutic treatment for cannabis addiction ("naive" patients) Reported use of cannabis more than three times a week in the past three years Signing consent to participate in research Exclusion Criteria: Pregnancy or lack of effective contraception Patients with severe somatic disease Other addictions of "moderate" to "severe" intensity according to DSM 5 criteria (excluding tobacco and coffee) Patients undergoing antidepressant or neuroleptic or thyroid-regulating therapy. Contraindications to tDCS (presence of an intracranial metal body, intracranial hypertension) Topic that has already been stimulated by tDCS Patients under reinforced guardianship or curatorship