Internet Gaming Disorder: A Case for Addiction?

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Table 1 – Comparison of DSM-5 Substance Use Disorder and Internet Gaming Disorder diagnostic criteria

Category

Substance Use Disorder (Addiction)

Internet Gaming Disorder

Impaired Control

Use for longer periods of time, or of larger amounts than intended

Unsuccessful attempts to control, limit, or stop use

Unsuccessful attempts to control participation in gaming

Excessive time spent getting/using/recovering from substance use

Cravings, strong desire, or urges to use substance

Preoccupation with games

Use of gaming to escape or relieve a negative mood

Social Impairment

Continued use despite problems with work, school, or family/social obligations

Jeopardy or loss of a significant relationship, job, or educational or career opportunity because of participation in games

Deception of family members, therapists, or others regarding the amount of gaming

Continued use despite interpersonal problems caused by substance

Continued excessive use of games despite knowledge of psychosocial problems

Loss or reduction of important recreational activities due to substance use

Loss of interest in previous hobbies and entertainment, as a result of, and with the exception of, gaming

Risky Use

Repeated use of substance in physically dangerous situations

Continued use in the knowledge of worsening physical and psychological problems caused by the substance

Pharmacological Indicators

Tolerance – an increase in the amount of the substance needed to achieve the same desired effect

Tolerance – the need to spend increasing amounts of time engaged in gaming

Withdrawal – the body’s response to the abrupt cessation of a drug, once a tolerance has been developed

Withdrawal symptoms when gaming is taken away

Note: the criteria presented in this table originate from Horvath et al. (n.d.) and the DSM-5 (APA, 2013)

With the exception of the risky use category, IGD and addiction exhibit similar symptoms across the board in impaired control, social impairment, and pharmacological indicators. These similarities between IGD and addiction criteria are perhaps to be expected on the basis of previous research, which has found that like substance addictions, non-substance addictions manifest in similar psychological and behavioural patterns including craving, impaired control, tolerance, withdrawal, and high rates of relapse (Marks, 1990; Lejoyeux, Mc Loughlin & Ades, 2000; Potenza, 2006). However, one apparent difference between making the two diagnoses is that for addiction only two of these need criteria need to be met over a 12-month period versus five in IGD (APA, 2013).

Prevalence of IGD

A number of studies have reported the prevalence of IGD using nationally representative samples. Among these, prevalence reports range from 8.5% among US youths aged 8-18 years (Gentile, 2009), to 1.2% among German adolescents aged 13-18 years (Rehbein et al., 2015). However, historically, IGD is a condition which has been inconsistently assessed, with constructs often based on adaptations of the criteria for pathological gambling or substance use disorders (Pontes et al., 2014). This being the case, there is no general consensus on the prevalence of IGD (Griffiths et al., 2016). A review of problematic gaming studies by Griffiths et al. (2015) found a large variance in prevalence rates among Australian students (from 0.2% to 34%). The authors attribute this to variances between studies such as, the type of gaming examined (e.g. online, console, both), participants (solely gamers, or general population), sample size, age range, and instruments used to assess gaming.

Common features of behavioural and substance-related addictions

Neurobiological processes

Though they may only act indirectly on the neurotransmitter systems of the brain, behavioural addictions can serve to reinforce behaviours in a way comparable to the pharmacological substances that directly affect the systems associated with addiction (e.g. dopaminergic system, serotonin system) (Grant et al., 2010). Indeed, the notion that the development and maintenance of both behavioural and substance addictions are underlined by common mechanisms is supported in the literature (Pontes, 2006; Albrecht, Kirschner & Grusser, 2007).

Given the significant role of dopamine in reward, studies on addiction and reinforcing behaviour have largely focused on investigating dopamine transmission (Yau & Potenza, 2015). Indeed, the one physiological effect that all reinforcing behaviours have in common, is the release of dopamine from the nucleus accumbens (White et al., 1996). Building upon the work of Olds and Milner in 1954, in which they identified the “pleasure-centre” of the brain, researchers were able to identify the mesolimbic dopamine reward pathway, just one structure that forms part of the brains reward system (Bardo, 2013). The mesolimbic dopamine reward pathway is the pathway most commonly associated with reward, it begins in the mid-brain ventral tagmental area (VTA) and travels to the nucleus accumbens (NAcc). The pathway is used to project dopaminergic neurons (dopamine releasing) primarily from the VTA to the NAcc, but also to the limbic and prefrontal cortical structures of the brain. It is believed to regulate motivation, salience attribution, learning, and fear (Malenka, Nestler & Hyman, 2009; Engert & Pruessner, 2008).

In normal function, the mesolimbic dopamine reward pathway mediates an individual’s responses to natural reward. By encouraging