Behavioral Studies Of Excessive Internet Users' Cognitive Functions

Excessive Internet use (EIU), also described as Internet addiction or pathological Internet use, is defined as an individual's inability to control his or her use of the Internet, which eventually causes psychological, social, academic, and/or work difficulties in life. EIU has already become a worldwide serious social problem and has attracted much attention from psychologists, educators, and the public. By using survey approaches, several studies focused on aspects such as assessment criteria, epidemiology, and psychiatric co-morbidity of EIU. However, limited data from experimental studies are available on cognitive functions of excessive Internet users (EIUers); such studies may provide the development of EIU treatment and prevention strategies. In the studies described in this dissertation, we studied emotion, inhibition, decision-making and executive control functions of EIUers, and we got some interesting results. Moreover, EIUers' behavior is much like that of drug abusers' and pathological gamblers'. Some researchers suggested EIU as a kind of behavioral addiction. Thus, cognitive links between EIU and other addictive behaviors were also discussed.In the first study, we examined EIUers' functions of decision-making and prepotent response inhibition. Two groups of participants (EIUers and controls) were compared on these two functions by using a Gambling Task (a modified Iowa Gambling Task) and a Go/no-go Task, respectively. The findings from the Gambling Task indicated that EIUers have deficits in decision-making function, which are characterized by a strategy learning lag rather than an inability to learn from task contingencies. Interestingly and surprisingly, different from patients with ither addictive behaviors, EIUers showed higher accuracy under the no-go condition in the go/no-go task.. However, EIUers could hardly suppress their excessive online behaviors in real life. Their ability of inhibition still need to be further studied with more specific assessments. These results showed some similarities and dissimilarities between EIU and other addictive behaviors such as drug abuse and pathological gambling.In the second study, we focused on excessive computer game playing (ECGP), a subtype of EIU. Limited data from experimental lab studies are available about the negative consequences of ECGP on players' cognitive characteristics. In this study, we compared three groups of participants (current ECGP participants, previous ECGP participants, and control participants) on a Multiple Object Tracking (MOT) task. The previous ECGP participants performed significantly better than the control participants, which suggested a facilitation effect of computer games on visuospatial abilities. Moreover, the current ECGP participants performed significantly worse than the previous ECGP participants. This more important finding indicates that ECGP may be related to cognitive deficits.In the third study, we studied EIUers' functions of emotion, inhibition, decision-making and executive control. We used self-reported satisfaction scale, Zung depression scale and more detailed questionnaires of SCL90 and WHOQOL-BRIEF to study emotional states of EIUers. We have reported in the first study that EIUers showed better ability to inhibit prepotent responses. In the present study, we studied EIUers' abilities of resistance to distractor interference and proactive interference by CFQ and WBSI questionnaires, respectively. We have showed in the first study that EIUers have deficits in decision-making function, which are characterized by a strategy learning lag rather than an inability to learn from task contingencies. To study EIUers' decision-making functions, in the current study, we used more decision-making experimental paradigms including Kirby and Richards delay discounting task which can measure if participants prefer immediate reward to future larger reward, and Cambridge Gambling Task which can measure participants' risk-seeking behavior. We also studied EIUers' function of executive control with Wisconsin Card Sorting Test (WCST). Results of the third study are being analyzed now. We will report these results in future.Our study of is a good start point to research EIUers' cognitive functions with experimental methods. Results of our studies may help diagnosing and treating EIUers. Based on our study, more researches should be taken on EIUers' neural activities and different factors (e.g. age, gender, education and culture) influencing on EIUers' behaviors.Some of the work described in this dissertation was appreciated by other researchers. One of the reviewers of CNS Spectrum commented on the paper of study I "Overall, the paper was well written and deals with a new area of research. As the field of Internet addiction (excessive Internet use) continues to grow, this papers adds to the fundamental understanding of the disorder. The design is helpful in understanding factors that are predictive of incidence and remission. The authors apply a number of assessment measures and gather a relatively good sample size to support their findings which provides an initial view of similarities and dissimilarities in decision making function between excessive Internet uses and other addictive behaviors." (more comments please see attached files after the first page of the article of study I)The result of Studyâ… was accepted by CNS Spectrum (Impact Factor 2007: 2.222); Studyâ…¡has already published on Cyberpsychology & Behavior (2008, 11: 545-548, Impact Factor 2007: 1.368). Studyâ…¢is now in the stage of research paper writing.