Alcohol can also exacerbate impulsive tendencies. Johansson, Bergvall, & Hansen (1999) found that rats with ibotenic acid-induced neuron loss in the basal forebrain showed increased alcohol consumption, which augmented aggression, insensitivity to punishment, and inattention to future rewards. These characteristics resemble those of alcohol abusers who demonstrate high rates of violence, impulsivity, and signs of reduced serotonin functioning in the brain. Interestingly, the same results were not evident with serotonin depletion alone, suggesting that these effects are also mediated by non-serotonergic mechanisms in the forebrain. More recently, Oliver, Ripley & Stephens (2009) examined the acute effects of alcohol on attention and response control aspect of impulsivity using a 5-choice serial reaction time task in two mouse strains. Although alcohol did not affect attention and impulsivity in the standard procedure, it did increase premature responding in the long inter-trial-interval sessions. Using rats, Nasrallah, Yang and Bernstein (2009) examined whether alcohol exposure in adolescence alters decision making and risk preference in adulthood. Using a probability-discounting instrumental responses task that offered a choice between a large uncertain reward and small certain rewards, these
