title: Decision-making and prepotent response inhibition functions in excessive internet users.
abstract: BACKGROUND
  Excessive Internet use (EIU), also described as Internet addiction or pathological Internet use, has already become a serious social problem around the world. Some researchers consider EIU as a kind of behavioral addiction. However, there are few experimental studies on the cognitive functions of excessive Internet users (EIUers) and limited data are available to compare EIU with other addictive behaviors, such as drug abuse and pathological gambling.
  
  
  METHODS
  In the present 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 and a Go/no-go Task, respectively.
  
  
  RESULTS
  Compared with controls, EIUers selected significantly less net decks in the Gambling Task (P=.007). Furthermore, the EIUers made progress in selecting strategy, but more slowly than did the control group (EIUers, chunk 3 > chunk 1, P<.001; controls, chunk 2 > chunk 1, P<.001). Interestingly, EIUers' accuracy during the no-go condition was significantly higher than that of controls (P=.018).
  
  
  CONCLUSIONS
  These results showed some similarities and dissimilarities between EIU and other addictive behaviors such as drug abuse and pathological gambling. 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. EIUers' better performance in the Go/no-go Task suggested some dissociation between mechanisms of decision-making and those of prepotent response inhibition. However, EIUers could hardly suppress their excessive online behaviors in real life. Their ability of inhibition still needs to be further studied with more specific assessments.
authors.affiliation: Division of Bio-X Interdisciplinary Sciences, the Hefei National Laboratory for Physical Sciences at Microscale, the Cognitive Neuropsychological Laboratory, School of Life Sciences, University of Science and Technology of China, Hefei, China.
authors.forename: De-Lin
authors.initials: DL
authors.lastname: Sun
authors.forename: Zu-Ji
authors.initials: ZJ
authors.lastname: Chen
authors.forename: Ning
authors.initials: N
authors.lastname: Ma
authors.forename: Xiao-Chu
authors.initials: XC
authors.lastname: Zhang
authors.forename: Xian-Ming
authors.initials: XM
authors.lastname: Fu
authors.forename: Da-Ren
authors.initials: DR
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D016739:Behavior, Addictive / Q000503:physiopathology / Q000523:psychology*; D003071:Cognition; D003657:Decision Making; D005260:Female; D005715:Gambling / Q000523:psychology*; D006801:Humans; D007266:Inhibition, Psychological; D020407:Internet; D008297:Male; D009483:Neuropsychological Tests; D011597:Psychomotor Performance; D055815:Young Adult