The Internet has become a basic tool for trading, entertainment, communication, as well as education in the contemporary world. Nevertheless, despite the high speed of information flow and potential educational value of the Internet, there are several attributes of the Internet which may foster addictive behavior. These attributes include easy and flexible access 24 hours a day; anonymity; provision of free, diversified, and unlimited number of social networks without geographical boundaries; greater control over one’s self-presentation; and provision of numerous opportunities to fulfill the need for belongingness as well as to escape from emotional difficulties, problematic situations, and personal hardships.
Internet addiction commonly refers to an individual’s inability to control his or her use of the Internet (including any online-related, compulsive behavior) which eventually causes one’s marked distress and functional impairment in daily life. Research findings have shown that excessive use of Internet or Internet addiction adversely affects one’s physical health, family life, and academic performance. Concerning the negative consequences of Internet addiction on one’s physical health, persistence of sleep deprivation may harm one’s immune system, thus increasing one’s vulnerability to assorted diseases. The lack of exercise due to excessive use of computer by maintaining a sitting posture may also risk suffering from carpal tunnel syndrome, back pain, and eyestrain. Concerning family problems caused by Internet addiction, family relationships are seriously disrupted by Internet addicts due to the decrease in time spending with family, reluctance of performing family duties such as doing household chores, and increase of conflicts with family in the negotiation for time spent on the Internet. Academic problems caused by Internet addiction include decline in study habits, significant drop in grades, missing classes, increased risk of being placed on academic probation, and poor integration in extracurricular activities. Besides, adolescent Internet addicts often suffer from severe psychological distress, such as depression; anxiety; compulsivity; feeling of self-effacement; fear that life without Internet would be boring, empty, and joyless; as well as feeling of loneliness and social isolation. In addition, people addicted to the Internet games may excessively imitate the behaviors and values of the characters in online games.
In view of the possible negative influence of Internet addiction on human development, there is a need to have a thorough understanding of the nature of Internet addiction. There are several sections in this chapter. First, a historical review of Internet addiction is presented. Second, the conceptualization and assessment of Internet addiction are discussed. Third, prevalence data of Internet addiction are described. Fourth, major theoretical accounts of Internet addiction are presented. Fifth, risk factors and protective factors related to Internet addiction are discussed. Sixth, intervention models of Internet addiction are outlined. Finally, the future research directions are examined.