|Should we classify video game addiction as a clinical disorder?|
Excess video game play may lead to a video game addiction, in which some online video games create a virtual world that can have major impact on our social and mental wellbeing.  Online video game addiction has not been classified as a clinical disorder yet. However with current research, behavioral addictions (which only includes gambling addiction at the moment) are now proposed as to be clinical disorders in DSM-5 (5th version of American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders) due to their similarity to substance addictions.  Unfortunately, due to lack of research, internet gaming addiction is only listed in the manual's appendix. Nonetheless, this idea has opened the doors to a whole new window of research. There is a strong drive towards investigating the neural mechanisms behind this type of addiction. Identifying the neural processes can be applied to what treatments can be used and individuals who might be more prone to having a video game addiction.
1 Brain Changes
|Cue-induced activation brain regions that are higher in video game addicts compared to control|
Currently, the largest problem in field of video game addiction is the lack of research, which explains why most of these studies are used for identify whether there are relationships between Substance Addiction and video game addiction.
1.1 Cue-induced Activity
Various neurological methods were used in numerous studies observing cue reactivity in video game addicts. After playing for 6 weeks, when excessive gamers were presented with game cues, they had higher activity in the anterior cingulate and orbitofrontal cortex (OFC) than causal gamers. Results measured by 3T blood oxygen level dependent fMRI were compared to a self-report to find cravings were positively linked with the anterior cingulate changes in all gamers. These two areas are part of the prefrontal cortex, which is thought to be important in drug cravings. In another fMRI study, the brain images of addicts and non addicts were subtracted from each other to further confirm that the brain regions involved in cravings are the DLPFC (dorsal lateral prefrontal cortex), the inferior parietal lobe, and the anterior cingulate cortex. The DLPFC is associated with reward motivation after receiving expectation, while the OFC may be responding to the expectation of reward. Even though these two fMRI studies show different areas of activation in the prefrontal cortex, both areas are associated with reward and addiction whether during or after the expectation of reward.
One study used EEG (electroencephalography) recordings to identify areas involved with emotional information from game-related and unrelated cues. Excessive gamers had stronger ERPs (event-related potentials) in the parietal regions of the brain when induced with game cues rather than casual gamers. The excessive gamers also displayed more arousal from game-cues than non-game cues. The inferior parietal lobe is associated with attentional allocation. This provides evidence that similar to drug addicts, salience of game cues and sensitization of the mesolimbic dopaminergic system may preserve the behaviour of excessive playing in addicts.
1.2 Dopaminergic System
The dopaminergic system involved in rewards and reinforcing behaviours has been show to play a role in video game play as one study shows evidence of higher dopamine release in the ventral striatum while playing video games. Such the dysfunction of dopaminergic systems should play a role in video game addiction. Authors in one study used SPECT (single photon emission computed tomography) to observe computer gamers’ dopamine release and noticed there was reduction of dopamine D2 receptor in the caudate after playing an online game. Another paper shows similar results in internet addicts using PET (positron emission tomography). Substance addictions are also associated with dysfunctional dopaminergic systems, see Receptors in Addiction.
There are genetic polymorphisms related to the dopaminergic system that are correlated to excessive video game play. The Taq1A1 allele of the dopamine D2 receptor gene and the low-activity version of the Val158Met alleles in the Catecholamine-O-Methyltransferase (COMT) gene had increased frequency in the excessive gamers than the casual gamers. Individuals with the Taq1A1 allele have a reduction in their D2 dopamine receptor binding sites, and it has been shown that these individuals are more likely to behave in impulsive or addictive behaviours. The low activity allele for COMT is suggested to be associated with intense euphoria which may increase the risk of excessive online gaming. Both polymorphisms have been studied intensively in substance and general addiction, see Genetics of Addiction.
1.3 Cognitive Effects
After excessive game playing in game addicts, researchers used regional homogeneity method to show that the resting-state of the brain increased in the areas involved in synchronizing sensory and motor information, specifically in the brainstem, left posterior cerebellum, inferior parietal lobe, and the left middle frontal gyrus. The enhanced coordination may be due to the fact that video game play requires controlling a character for fighting or killing enemies. A decline in regional homogeneity was found in areas for vision and audition, particularly in the temporal, occipital and parietal lobes. The fact that gamers are exposed to visual and auditory information for many hours every day may be the cause to a decrease in excitability in these areas. However, there are Cognitive Benefits of Video Games.
2.1 Video Game Genre
|Is this boy at risk for video game addiction?
Image source: http://o.canada.com/2013/01/04/dad-hires-virtual-hitmen-to-stop-son-from-playing-video-games/
Video games are categorized into different genres and these genres include Massive Multiplayer Online Role-Playing Games (MMORPGs), board/card games, sports games, gambling games, First Person Shooter (FPS) games and others game types. These games differ in their game design and the type of game played is thought to be a predictor for whether one develops a gaming addiction. Results from a recent study have shown that although board games and card games were the most played, MMORPGs and FPS are the two genres that cause the greatest addiction in gamers.
There is confirming evidence that FPS players will have higher addiction rates, but most of the studies used to investigate video games addictions involve a genre called Massively Multiplayer Online Role-Playing Games. (MMORPGs). Being addicted to MMORPGs may have negative consequences on school and social interactions.  One study indicates two psychological predictors can cause these negative effects. The first predictor is acting impulsively in response to negative moods will cause players to use video games to avoid negative affect states, until these behaviours become automatic. The second predictor is motivation to play video games as a way to escape real life, possibly to avoid negative their feelings. This behaviour may cause guilt/shame and will lead to a vicious cycle of low self-esteem, negativity and addiction.
2.2 Age and Gender Differences
Many of the studies used to examine video game addiction use adolescent males as their participants, and this does not occur without reason. Griffiths, Davies, and Chappell (2004) used a questionnaire survey to indicate age plays a role in excessive game play. They found that younger adolescent players play longer, were more likely to skip school/work to play and enjoy the violence in the video game more than adults. It was interesting to note that both age groups enjoyed the social part of gaming and may reinforce the idea that social factors may have a role in excessive game play. see below for Social Aspect. Currently, there are no neurological age-related studies on video game addiction. However, a study on substance addiction notes that adolescents are more vulnerable to addiction due to the normal reorganization of neural circuitry in the DLPFC, the superior temporal cortex (areas involving executive function and social cognition, respectively) and other areas during adolescence that are found to increase drug-use behaviours like social conformity and sensation-seeking. These regions could be areas of interest for researchers studying the association between age and video game addiction.
Males are more likely to play online games overall and also more likely to become addicted compared to females. There is also evidence that shows males will choose to play MMORPGs and FPS more, and as discussed previously, these are the genres that are associated with a higher risk for addiction. There is some argument that some video games were created specifically for males, which lead them to be more attracted to them. However, another paper suggests that males and females use games to fulfill different social needs. Examining neurological differences might help understand why there seem to be gender differences. The nucleus accumbens (NAc) and the orbital frontal cortex (OFC), areas associated with reward, were activated for both genders. Specific function of the OFC is to code the value of reward, and with the NAc, they function to represent predicted reward in the future. In general, males had higher activation and connectivity in the mesocorticolimbic reward circuitry than females in a repetitive space-changing game. Overall, the game was more rewarding for males than females, and since these activated neural substrates overlap with general addiction, these areas may help us explain the gender differences in excess gaming.
2.3 Social Aspect: Self-Identification with Avatars
Video games have grown to become more social over the decades, and many gamers gain friends and even partners, in which video games like MMORPGs create a virtual realm that allows for self-expression that may be more ideal than reality. With a need to escape reality, one study shows evidence that addicted gamers want to be like their characters in reality and that younger gamers are more likely to become addicted. Currently, there are no neurological studies done to study how the social aspect of video games is related to video game addiction specifically. However, a recent study shows that there is some neural activation when identifying with virtual avatars. fMRI brain scans of long-term gamers indicate there is increased activity in the left inferior parietal lobe from an avatar-reference processing task Not all gamers are attached to their virtual character such that the degree of activation in this left interior parietal lobe positively correlates to how much they identify with external items, like avatars. The brain scans also show higher activation in the rostral anterior consulate gyrus in the same task in which its function is to assess emotional connection with the virtual character. Excessive activation in these two regions may be the areas of interest for researchers looking to study the addictive social aspect of online video gaming.
Since video game addiction is a relatively new and growing issue, there are limited number of treatments available. The lack of a universal criterion/definition for video game addiction limits research on both diagnosing and treating video game addiction.  More treatments are available for internet addiction which can be arguably be the under the same category.  However, the treatments discussed below are used specifically for online game addiction. Specifically, drug treatments from other associated mental disorders are applied to video game addictions.[32,33,35] see Treatment of Addiction for treatments on substance addiction, as it is very possible to see some of those treatments being applied to video game addictions in the future due to similar neural mechanisms.
3.1 Drug Treatment
The most studied drug treatment is Bupropion. It has been adapted from treating drug dependence to video game addiction and it is also used to treat depression.  Bupropion sustained release treatment administered to video game addicts resulted in lower DLPFC cue-induced activity and also decreased cravings.  In a follow up study, Bupropion was given to individuals suffering from comorbid Major Depressive Disorder (MDD) whom spend excessive amounts of time on gaming; it decreased their time playing games and also reduced depressive symptoms. More information is available on Addiction Comorbidity, however it is in relation to substance addiction. Bupropion with cognitive behavioral therapy has shown to be effective for depressed individuals to reduce game play and increasing their satisfaction with life. Methylphenidate, a treatment used to treat ADHD, has also been shown to be a possible treatment for video game addiction. This drug is a stimulant that works on the dopaminergic system to increase dopamine and has decreased gaming time in individuals with co-morbid ADHD and video game addiction. 
Behavioural therapies have shown to be another effective method used for treating video game addictions due to the social aspect of this addiction. For example, family therapy used to increase family unity, decreased the amount of online playing time and also the middle frontal and inferior parietal brain regions had increased activity when presented with gaming cues.  Another behavioural treatment called Short-Term Treatment of Computer-Game Addiction (STICA) is currently under-going clinical testing and trials are expect to continue until 2014. It aims to provide interventions that will help addicts get back their normal lives and will also take into account other comorbid disorders.