| Popis: |
Several models have been proposed to explain the progression from drug experimentation to regular use and addiction in persons with heritable risk. These include a two-factor model of the relationship between behavioral activation (i.e., decreased reward sensitivity) and behavioral control (i.e., decreased behavioral control). However, a more complex model suggests that different groups of individuals at risk exhibit different patterns of behavioral deficits. For instance, some at-risk individuals may show increased reward/sensation seeking and preference for smaller immediate rewards when others may show decreased reward sensitivity but also compromised ability to withhold behaviors that lead to negative outcomes. Physiological and neuroimaging studies have identified brain regions in individuals with familial substance use disorders (SUDs) that show different structural and functional patterns compared to unaffected controls. Although existing evidence prevents us from drawing a firm conclusion as to whether over- or underresponsive reward systems mediate the familial risk for developing SUDs, it is plausible that alterations in reward processing and behavioral control present a common deficit in individuals at familial risk for SUD. |
