The serotonin transporter (SERT) brain density and the neurobiological Cloninger subtypes model: a lesson by human autoradiography studies. Alcohol Alcohol

Abstract — Cloninger proposed a neurochemical model of alcoholism suggesting that type 2 alcoholics have serotonergic deficits with intact dopaminergic system, whereas the type 1 alcoholics have defected dopaminergic system. The work by Storvik and colleagues recently published on Alcohol and Alcoholism shows some interesting differences on the SERT brain density between the type I and type II alcoholic subtypes. Critically, these findings on different serotonergic role in subtypes of alcohol-dependence revive the concept that alcohol addiction is a heterogeneous disorder associated with varying neurochemical abnormalities. Studies testing serotonergic medications in alcohol-dependent patients classified according to subtypes have shown interesting findings. Accordingly, the identifica-tion and standardization of alcoholic subtypes could be useful in guiding research on treatment. New developments in the neurobiological understanding of subtypes of alcoholic patients, could led to get the basis for a more personalized pharmacological therapy. In 1981 Cloninger, Bohman and Sigvardsson (Cloninger et al., 1981) identified two alcoholic subtypes and named them type 1 and type 2. Cloninger typologies overlap to some extent with type A/B subtypes of Babor et al. (1992). In particular both typologies share the early (Cloninger 2 and Babor B) or late (Cloninger 1 and Babor A) onset. Type 1 alcoholics manifest fewer associated childhood antisocial behaviors; type 2 alco