The underlying biological mechanisms (both circuitry and molecular mechanisms) necessary for performance of various tests of impulsivity is not identical, but a core set of frontostriatal circuits is repeatedly implicated in various types of impulsivity and decision-making. As shown in Figure 1, there is a distinction between measures of impulsive behavior that rely upon more lateral, orbital regions of the frontal cortex and ventromedial, limbic portions. At the neuropharmacological level, there are also important distinctions, with responses to acute challenge with monoaminergic drugs and/or responses to chronic administration of addictive drugs being task-specific (Table 2).
