Genetic-linked Inattentiveness Protects Individuals from Internet Overuse: A Genetic Study of Internet Overuse Evaluating Hypotheses Based on Addiction, Inattention, Novelty-seeking and Harm-avoidance

Abstract The all-pervasive Internet has created serious problems, such as Internet overuse, which has triggered considerable debate over its relationship with addiction. To further explore its genetic susceptibilities and alternative explanations for Internet overuse, we proposed and evaluated four hypotheses, each based on existing knowledge of the biological bases of addiction, inattention, novelty-seeking, and harm-avoidance. Four genetic loci including DRD4 VNTR, DRD2 TaqlA, COMT Val158Met and 5-HTTLPR length polymorphisms were screened from seventy-three individuals. Our results showed that the DRD4 4R/4R individuals scored significantly higher than the 2R or 7R carriers in Internet Addiction Test (IAT). The 5-HTTLPR short/short males scored significantly higher in IAT than the long variant carriers. Bayesian analysis showed the most compatible hypothesis with the observed genetic results was based on attention (69.8%), whereas hypotheses based harm-avoidance (21.6%), novelty-seeking (7.8%) and addiction (0.9%) received little support. Our study suggests that carriers of alleles (DRD4 2R and 7R, 5-HTTLPR long) associated with inattentiveness are more likely to experience disrupted patterns and reduced durations of Internet use, protecting them from Internet overuse. Further-more, our study suggests that Internet overuse should be categorized differently from addiction due to the lack of shared genetic contributions. Keywords: Internet overuse; inattentiveness; dopamine receptor D4 gene (DRD4); serotonin transporter gene (5-HTTLPR); Internet Addiction Test Introduction The advent of the Internet age in the last decade provided the world with new landscapes of sociability and access. Lately, the growing role of the Internet, along with other new information technologies (e.g., mobile devices and applications), has become increasingly pervasive and influential in all aspects of our everyday life. With its impersonal method of communication, copious amount of information, and many other unprecedented features, the Internet has reshaped and redefined friendships, businesses, professions, academia, and entertainment. Meanwhile, the omnipresent Internet has created serious social and personal problems, everything from privacy theft (Aimeur & Schonfeld, 2011) and cyberbullying (Tokunaga, 2010) to Internet overuse. Is Internet Overuse a Type of Addiction? Since the term "Internet addiction" was first introduced in 1996 (Young, 1996), there has been considerable debate by both clinicians and academicians over whether it should be diagnosed, studied, and treated the same way as substance addictions such as alcohol, nicotine and drugs (Beard & Wolf, 2001; Campbell, Cumming, & Hughes, 2006; Mitchell, 2000; Murali & George, 2007; Young, 2004). The discussion has become even more contentious after pathological gambling became the first behavioral disorder recognized as a type of addiction by the American Psychiatric Association (2013). The controversy is also reflected in the use of terminologies. Besides Internet addiction, some refer to it as Internet addiction disorder (Bai, Lin, & Chen, 2001), whereas others prefer pathological Internet use (Morahan-Martin & Schumacher, 2000), or Internet dependency (W. Wang, 2001). In this study, the term Internet overuse is used to cover the collective phenomenon. Despite the debate and controversy, Internet overuse became a popular topic for research. Between 1996 and 2006, more than 120 peer-reviewed articles were published on Internet overuse and related subjects (Byun et al., 2009). Internet overuse has been most studied in East Asian countries such as China and South Korea (Weinstein & Lejoyeux, 2010). This seems to correspond with the high prevalence of Internet overuse and frequent tragic incidents related to Internet overuse in this region (Choi et al., 2009; Deng & Xuan, 2009; Lam, Peng, Mai, & Jing, 2009; Park, Kim, & Cho, 2008; Tsai et al. …