Transition to alcohol dependence: clinical and neurobiological considerations

The transition to alcohol dependence is supposed to occur during a critical period that begins with increased drinking and ends with a loss of control. This process may last about 3 to 4 years, and is modified by gender and accelerated by premorbid traits (e.g., novelty-seeking) and comorbid disorders (e.g., dissocial personality disorders according to ICD-10). Genetic disposition, environmental influences (e.g., stress), and sensitization by exposure are factors implicated in dependence that alter brain functions, some possibly in an irreversible way. Underlying neurobiological mechanisms that may have different time patterns are beginning to be characterized on a systemic, cellular, and molecular level. Repeated free choices of the rewarding compound seem to be necessary for the transition to dependence.