While a growing body of literature has examined internet addiction in the context of psychological factors, most of this work has focused on younger populations outside of the United States. A sample of 898 US adults ranging from 18 to 76 years of age were recruited through Amazon's Mechanical Turk platform to complete the Internet Addiction Test and key measures of affect, disposition, and cognitive function. A series of multiple regressions were conducted to examine Internet Addiction level as a predictor of outcome variables. ANCOVAs with Fisher 's LSD post-hoc analyses were conducted using level of internet addiction as the grouping variable to examine differences between groups. Results found that Internet Addiction was a significant predictor of depression, impulsiveness, self-control, need for cognition, theories of cognitive abilities, creativity achievement, cognitive failures, smartphone use behaviors, mental rotation test, and cognitive reflection test. Further, even mild levels of internet addiction were associated with less optimal outcomes. Additionally, a significant relation between age and internet addiction also emerged such that older adults were less likely to have higher levels of internet addiction than younger adults.

However, age did not appear to modulate the association between internet addiction status and key psychological variables. To further elucidate the mechanisms and impact of internet addiction throughout the life course, future studies should collect online and in-person data, from individuals across a variety of backgrounds, throughout the lifespan.