Serotonergic dysfunction also seems to be a cause of negative mood states, namely anxiety and depression (Barr et al 1994; Artigas 1995; Mann et al 1996). Among alcoholics, the association between serotonergic dysfunction and depression is less well established. Some genetic linkage and brain imaging studies, however, have suggested that a reduced availability of serotonin transporters is associated with anxiety and depressed mood states among alcoholics, patients with major depression, and control subjects (Malison et al 1998; Mazzanti et al 1998; Rosenthal et al 1998; Heinz et al 2001). Some studies indicate that the association between a low serotonin turnover rate and aggressive behavior may be mediated by negative emotions, such as feeling insecure and threatened. Virkunnen and colleagues (1994) observed that alcoholics with low serotonin turnover and high aggressiveness suffer from increased anxiety. A reduction in central serotonin turnover has been observed in heterogeneous groups of individuals, eg, alcoholics, violent criminals, and fire-setters. It has been suggested that “impulsive aggression” is the behavioral characteristic common to all of these individuals (Kruesi et al 1990; Virkunnen et al 1994).
