Addiction, Smoking
Conditions
Keywords
tobacco, smoking, tDCS, DLPFC
Brief summary
The aim of this study is to determine whether a powerful technique of noninvasive brain stimulation, transcranial direct current stimulation (tDCS), could reduce cigarette smoking and constitute a treatment of tobacco addiction.
Detailed description
Tobacco is estimated to cause more than 5 millions yearly deaths in the developed world. Although most smokers would like to quit, relapse rates remain high. It seems that this relapse is linked with the process of craving, which is a powerful desire to smoke elicited by smoking deprivation or exposure to situations or cues that are associated with smoking. Neuroimaging studies have shown that the dorsolateral prefrontal cortex (DLPFC), and especially the right part, is critically involved in processing the craving of smoking. Increasing the activity of the DLPFC by noninvasive brain stimulation has been demonstrated to be effective in decreasing craving symptoms in cigarette smokers. The aim of this study is to determine whether a powerful technique of noninvasive brain stimulation, transcranial direct current stimulation (tDCS), could reduce cigarette smoking. tDCS is a painless and safe brain stimulation method capable of modulating cortical excitability. The nature of these modulations depends on stimulation polarity: anodal tDCS is thought to cause neuronal depolarisation and thus enhancing cortical excitability whereas cathodal stimulation is proposed to reduce excitability. The investigators hypothesize that anodal tDCS applied repetitively to the right DLPFC could constitute a treatment of tobacco addiction. Therefore, the investigators will conduct a sham-tDCS-controlled, randomized, double-blind study.
Interventions
PROCEDUREsham tDCS
sham condition as delivered by the stimulator study mode (2mA during 40s and brief current pulses until the end of the stimulation) 20 minutes, 10 sessions, 2 per day
PROCEDUREactive tDCS
anodal tDCS applied over the right DLPFC 2mA, 20minutes, 10 sessions, 2 per day
Sponsors
Hôpital le Vinatier
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 55 Years
Healthy volunteers
Yes
Inclusion criteria
* Age from 18 to 55 years old * Tobacco consumption from 10 to 25 cigarettes, for at least 1 year * Strong tobacco dependence at the Fagerstrom Test (score \>= 5) * Motivation to quit with a score \>=12 at the Motivation to Quit Smoking Scale (Q-MAT) * Informed consent
Exclusion criteria
* Concomitant Axe I psychiatric disorder according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM IV) * Other addictive disorder (DSM IV) * No history of smoking cessation drug the previous year * Psychotropic treatment * Pregnancy or nursing
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Smoking | Baseline (three days before starting tDCS regimen) to one-month after | Self-reported number of cigarettes smoked each day |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Exhaled carbon monoxide | Baseline, one-week (after the last tDCS session) and one-month later | measured using a CO monitor (MicroCo, Milford, MA, USA). |
| Craving | For each of the 10 tDCS sessions: Baseline and 0 hour post-tDCS (immediately after) | measured using a 5-item Likert-type scale questionnaire of smoking urge |
| fMRI brain reactivity during a smoking cue-reactivity task | Baseline and one-week (after the last tDCS session) | measured using an event-related fMRI paradigm |
Countries
France
Outcome results
None listed