Internet gaming disorder (IGD) has long been characterized by inconsistencies in terminology, definition and assessment [1, 2]. We are largely in agreement, therefore, with many of Petry et al.'s [3] views on the need for consensus regarding the underlying meaning of the proposed DSM-5 criteria for IGD. A common method for assessing IGD criteria ensures greater consistency across future research investigations and clinical trials [4]. Unfortunately, however, an agreement on the wording of assessment items alone does not resolve the broader problem of the lack of consensus concerning the most appropriate conceptualization of excessive internet gaming as a behavioural syndrome. A potential obstacle for empirical research in this area remains the assumption (now enshrined in the DSM-5 classification) that harmful internet gaming is an addiction. Until there is greater collective acceptance and validation of this conceptualization, it is likely that research and clinical approaches, particularly in the discipline of psychology, will continue to emphasize other theoretical approaches.

One such approach which we believe is a case in point is the study of cognitive factors [5-8]. Many past studies of IGD [9-11] have focused predominantly on the degree to which an individual is preoccupied with internet gaming, as operationalized in research studies (including Petry et al.'s paper) as the extent to which an individual spends time thinking about internet games. Considerably less attention has been paid to the content of individuals' thoughts about internet games, and whether any such thoughts may differ systematically according to normal and clinical populations [12]. In related fields of excessive or addictive behaviour, such as eating disorders, obsessive–compulsive disorders and gambling disorder, significant advances in understanding core psychopathology have been achieved by attending to the content and structure of problematic beliefs and assumptions that govern behaviours that produce harmful consequences. For example, it is known that individuals with anorexia nervosa report frequent thoughts about their body shape and/or appearance, as well as distorted thinking about body image and a pathological fear of gaining weight [13]. As another example, pathological gamblers report a tendency to think about and plan gambling sessions, in addition to holding irrational beliefs related to the long-term profitability and degree of player control involved in gambling [14]. The concept of preoccupation alone does not encapsulate the variety of unique maladaptive cognitions in these disorders. Following this reasoning, it may be argued that individuals with IGD would possess a similarly idiosyncratic set of unhelpful beliefs that underlie and maintain excessive involvement in internet gaming activities.

Failing to acknowledge cognitive differences across syndromes may also promote an unfounded assumption that the same or similar treatment protocols may be applied successfully from one disorder to another [15]. One good example of this relates to the adaptation of cognitive–behavioural therapeutic interventions designed for gambling disorder to internet gaming disorder. Both gambling and video-gaming involve a repetitious behaviour undertaken to obtain intermittent rewards. Players make decisions, compete with an electronic device or other people, and time, money, and effort is invested to improve one's performance [16]. However, in contrast to most gambling games, each successive outcome and a person's progress through an internet video-game is much more deterministic; that is, determined largely by the player's choices and input into the game. Therefore, although both problematic gambling and video-gaming may involve an unhealthy preoccupation as a core cognitive symptom, most cognitive interventions for gambling would focus upon addressing erroneous beliefs relating to randomness, chance and probabilities. If internet gaming is largely a skill-based activity where there is a clear relationship between player strategy or actions and outcomes, then using gambling treatment protocols as a guide may be misleading.

As the legitimacy of IGD continues to be debated [17-19], we suggest that researchers also consider other psychological factors. While cognitive approaches are not the only factors that might be considered, we have emphasized this area because is likely to highlight differences between gaming and gambling that might not be differentiated so easily by traditional addiction models. It is our hope that greater attention be directed towards identifying and differentiating these factors at an epidemiological level, and that this work will lead to new applications. These include revisions to how consumer information concerning these disorders is promulgated in the community/self-help forums as well as possible refinements of cognitive–behavioural therapy for IGD for evaluation in clinical trials.

This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.