Neurobehavioural aspects of drug addiction. Some insights into physiopathology and possible treatment

Addiction is a complex disease process of the brain that results from recurring drug intoxication (Goldstein & Volkow, 2002). Drug addiction can be a devastating and chronic relapsing disorder with social, psychological and physical consequences, and more effective treatment options are needed (O'Brien, 2008). Accurate recognition of emotional facial expressions is an important adaptive function (Montagne et al., 2005). In particular, eyes expression is generally related with our perception of emotions. The ability to infer others' emotional states expressed through the eyes is relatively unexplored among individuals with opioid dependence. A neuropsychological study aimed to compare emotion recognition in methadone patients with healthy controls is presented. We found that methadone patients appeared to have less ability to decode others' emotional states based on eyes expression compared to controls. This finding, if confirmed in a larger sample, might be useful in guiding counseling approaches. While great progress has been made in identification of effective behavioral therapies and pharmacotherapies for the addictions, no existing treatment, delivered alone, is completely effective (Carroll & Onken, 2005; Vocci et al., 2005). Repetitive Transcranial Magnetic Stimulation (rTMS) is a non-invasive brain stimulation technique that has been assessed in a growing number of studies for its therapeutic potential in treating addiction (Bellamoli et al., 2013). Our rTMS randomized clinical trial aimed to assess the effectiveness of introducing rTMS sessions in a program of hospitalization for the treatment of alcohol or drug addiction, in reducing alcohol consumption and the severity of craving. Psychological and neurophysiological variables were also measured for more comprehensive assessment of the treatment effects. In this single-blind, sham-controlled study, participants were administered 4 sessions of high frequency rTMS over the left dorsolateral prefrontal cortex (DLPFC). We did not found significant effect on subjective craving and consumption, and analyses of results suggested that further studies are needed to identify the optimal parameters of stimulation for the most effective treatment of drug addiction, to improve our comprehension of the rTMS effects, and to conduct controlled efficacy studies with adequate sample.