the tendency not to delay responding in order to obtain a larger reward (Dougherty et al. 2005b). A tendency to prefer immediate over delayed rewards is considered to be an aspect of impulsivity that is potentially important to addiction, since addictive disorders are typified by a choice of the use of a substance in the present, often at the expense of concern about future outcomes. Accordingly, alcohol-dependent and other addicted individuals tend to discount future rewards more steeply than non-addicted individuals (Bickel et al. 2007). The fifth type of task involves distorted judgments of elapsed time (Dougherty et al. 2005b).
