Title: Problematic Internet Use
Description: In this dissertation I present original research supporting the conceptualization of problematic Internet use as an expression of the addiction syndrome. In the first two chapters, I review the history of the diagnosis and current methods for assessing and modeling Internet addiction. This includes a review of the literature on Internet addiction which focuses on the relationship of psychiatric disorders to Internet use and establishes a background for the current research. In four empirical chapters, I present the results of three related studies which examine Internet use across a spectrum of normative to pathological behavior. First, I describe a national survey of online behavior in people who use the Internet daily with the goal of establishing a normative baseline for Internet use. 

Next, I present a study which evaluates problematic Internet use in players of massively-multiplayer online games (MMOs) at low and high levels of problematic behavior, with the goal of identifying clinical and personality factors which distinguish more problematic use, in the specific context of MMOs. In the next chapter, I present the results of the first study using the Schedule for Nonadaptive and Adaptive Personality - 2nd Edition (SNAP-2) in heavy Internet users. The goal of the study is to delineate the personality characteristics of Internet users when compared to normal personality data. The results support the idea that personality represents a distinct antecedent for excessive Internet use, which may be relevant in determining risk for Internet addiction as opposed to other types of addiction. Building on these findings, I then present a laboratory study which evaluates cognitive impairment as another potential risk factor for problematic Internet use. 

This study examines cognitive performance of heavy recreational Internet users across three executive function tasks - the Iowa Gambling Task, Wisconsin Card Sort Task, and the Go/No-go Task - in order to determine whether heavier Internet use is associated with executive dysfunction. These findings are then evaluated in a final discussion chapter. The results of this work establish Internet addiction as a unique expression of the addiction syndrome, both similar to and distinct from both other behavioral addictions and substance-related disorders.