Neuroimagen y adicción IIcorrelatos neuroanatómicos y funcionales de la administración aguda, el craving y el consumo crónico de opiáceos, alcohol y cannabis

Résumé

In the last decades neuroimaging techniques have greatly contributed to the �in vivo� study of the neurobiological effects of drugs of abuse, both acutely and long-term. The increases in the use of alcohol and cannabis, and the serious consequences stemming from opiod use have further fostered the interest for investigating the effects of these substances on the central nervous system. The aims of this review are: (1) To outline the most updated neuroimaging findings in the study of the neural correlates of opioids, heroin and cannabis use; here, we will consider (i) acute administration of the drug, (ii) experimentally-induced craving, and (iii) chronic effects of prolonged drug use. (2) To discuss the relevance of these findings for a better comprehension of addictive disorders and their treatment. The findings reviewed indicate that the use of these drugs is associated with shared structural and functional alterations in several regions of the frontal cortex and limbic system; with subtle discrepancies on the intensity and extent of these alterations. Moreover, these same regions show hyperactivation during experimentally induced craving states, and display abnormal activations during stimulation with pertinent cognitive paradigms. The observed brain alterations have been associated with clinical symptoms, such as comorbid psychiatric disorders, intensity of craving in naturalistic conditions, and the risk of relapse. Therefore, the use of new techniques based on modulation and fine-tuning of brain function constitute a promising approach to improve treatment outcomes in addictive disorders.