Category Archives: Video games
Coining it in: Neologisms and ‘New Syndrome’ Syndrome
One of things I am very proud of in my academic career is the coining of the term ‘technological addiction’ back in 1995 (an umbrella term that I invented to describe a number of different person-machine addictions including slot machine addictions, video game addiction, television addiction, etc.). I’m also proud of coining the term ‘aca-media’ (relating to academics like myself that use the media to disseminate our research). A neologism (i.e., the name for a newly coined term) is often (according to Wikipedia) directly attributable to a specific event, person, publication, or period.
In the 1980s and early 1990s, there seemed to be a real upsurge is the naming of ‘new syndromes’ in the medical literature including many relating to excessive use of technology (such as ‘Space Invader’s Wrist’) and other leisure activities (such as ‘Cuber’s Thumb’ relating to excessive use of the Rubik’s Cube) – both of which made their appearance in 1981 issues of the New England Journal of Medicine. Other videogame medical complaints include ‘Pseudovideoma’ (in a 1984 issue of the Journal of Hand Surgery), ‘Pac-Man Phalanx’ (in a 1983 issue of Arthritis and Rheumatism) and ‘Joystick Digit’ (in a 1987 issue of the Journal of the American Medical Association). Another videogame-related medical complaint (in this case an infection), was reported in a 1987 issue of the Western Journal of Medicine by Dr. G.B. Soe and colleagues:
“We wish to focus WJM readers’ attention on another complication associated with video games-one that originally presented as an “infected spider bite. A 17-year-old right-handed boy noted progressive swelling and redness of his left hand seven days before admission. Two days before admission he was given penicillin intramuscularly and oral cephalexin to take at home. The swelling did not subside and the hand became very painful, so he came to the medical center for treatment. On admission his mother reported that she had seen many spiders around the house with a violin pattern on their backs, and that her son had probably been bitten by a spider…After seven days of parenteral antibiotic therapy, the edema, erythema and fever had disappeared and the patient was discharged home. Further questioning revealed that the young man was spending almost all of his time playing his favorite video game, which involved a fighting kung fu character. The patient used his left hand in manipulating a ball-shaped joystick to move the figure up, down, left and right, and his right in operating buttons to kick and jab. Extensive use of the joystick resulted in blisters on his left palm. He rubbed the blisters off, and an infection resulted that progressed to abscess formation. Neuromuscular complications of video games (‘pseudovideoma’, ‘Pac-Man phalanx’, ‘firing-finger syndrome’ and ‘Space Invaders wrist’) have been reported, as well as video game-induced seizures, but we have not come across any reports of an infectious complication of video games. Perhaps video game players should wear gloves to protect their palms, similar to ones worn by golfers and baseball players, who also need to get a firm grip on their respective sticks”.
Another one that I’d never heard of is ‘Nurd Knuckles’ coined by Dr. J.B. Martin in the Canadian Medical Association Journal in 1982:
“I wish to describe a case of painful knuckles associated with the use and manipulation of a new, allegedly therapeutic product, a Nurd. A Nurd is a head 10 cm across with a smiling face and large ears, reminiscent of the character Yoda of ‘Star Wars’. It is made of malleable material that can be stretched, twisted or deformed in any direction, yet with release of tension quickly resumes its original shape without a trace of distortion. A 32-year-old public school teacher presented with painful knuckles of his right hand. His students, perhaps feeling that their teacher was under increased stress during the marking of exams, had given him a Nurd for Christmas, and during a particularly trying day he had found occasion to use it. He repeatedly stretched its ears and twisted its neck without ill effect; however, on punching it he suffered sharp pain of his fourth and fifth metacarpophalangeal joints. On examination the joints were found to be reddened, with point tenderness over the fifth metacarpal head; there was no evidence of deformity. He was advised to stop beating his Nurd, and the pain subsided. While the Nurd is very plastic, yielding to the linear tension of stretching and twisting, it is very resistant to compression. Punching a Nurd does not cause the surface to give way, and, since the force of the blow is returned to the fist, it is conceivable that a fracture might result. Therefore, although stretching and twisting Nurds does not cause any harm, users should be cautioned against punching their Nurd. The Nurd is advertised as being a ‘punchable, stretchable, pushable and likeable alternative to tension, migraine headaches, drug abuse, alcoholism and manic depression’, but these claims are unsubstantiated. A MEDLINE search of the medical literature shows that no retrospective or prospective case control studies or controlled double blind crossover studies have been undertaken. Before the clinical efficacy of the Nurd can be taken seriously in the treatment of this broad spectrum of disease, full clinical trials must be completed. Subjects entering into trials must, however, be duly informed of the hazards of punching Nurds”.
Another one that caught my attention was a new affliction (‘Breaker’s Neck’) caused by the craze of ‘break dancing’ reported by Dr. Bertha Ramirez and her colleagues in a 1984 issue of the Journal of the American Medical Association. (The reason why I say it caught my eye is that I am currently involved in some research on ‘dancing addiction’ with some of my Hungarian colleagues and we have just had a new paper accepted in the journal PLoS ONE concerning the development of our ‘Dancing Motives Inventory’ – see ‘Further Reading’ below).
“To be added to the rapidly growing list of socially acquired injuries, we report a case of traumatic cervical subluxation caused by a new dance technique. This technique, labeled ‘breaking’ by its devotees, involves a modified head stand, in which the dancer, using his arms and hands for balance, spins rapidly on his head, neck, or shoulders to the rhythm of disco music. He then lowers his body to the floor and performs a series of rotational motions using his arms as a fulcrum…A 15-year-old boy was seen in our pediatric emergency room complaining that, on awakening two days previously, he felt a ‘snap’ in his neck, followed by persistent neck stiffness. He reported having ‘danced on his head’ the night prior to this incident. On physical examination, his head was tilted to the left with an inability to flex”.
Engaging in excessive sporting activity has given rise to a number of medical syndromes. One such consequence is ‘Rower’s Rump’ reported by Drs. K Tomecki and J. Mikesell in a 1987 issue of the Journal of the American Academy of Dermatology. In a previous blog I examined addiction to cycling. In the 1980s there were many medical complaints reported as a result of excessive cycling. One such complaint (given the name of ‘Bicycling nipples’) was highlighted by Dr. B. Powell in a 1983 issue of the Journal of the American Medical Association:
“Bicyclists are likely to suffer from a number of maladies, including dysuria, numb penises, and more. During cool or cold weather, another problem, bicyclist’s nipples, may occur. This condition is similar to jogger’s nipples, but it is primarily a thermal injury instead of an irritation secondary to friction, as with the jogger’s complaint. Often the rider is out in the cold weather for some time, and his or her undershirt, jersey, and jacket can become moist from perspiration. Evaporation and the chill of the wind lower the temperature of the nipples. They get downright cold, and they hurt. The pain continues after the ride is over. Indeed, it can continue for several days. The nipples are sore, sensitive to both temperature change and touch”.
After reading this I found out that Dr. Fred Levit had reported a case of ‘Jogger’s Nipples’ in a 1977 issue of the New England Journal of Medicine. All of these related nipple conditions are all examples of fissure of the nipple as they are all caused by friction resulting in soreness, dryness or irritation to, or bleeding of, one or both nipples. The Wikipedia entry also notes that “the condition is also experienced by women who breastfeed, and by surfers who do not wear rash guards”. The article also noted that:
“Jogger’s nipple is caused by friction from the repeated rubbing of a t-shirt or other upper body clothing against the nipples during a prolonged period of exercise. The condition is suffered mainly by runners. Long-distance runners are especially prone, because they are exposed to the friction on the nipple for the greatest period of time. However, it is not only suffered by athletes; the inside of a badge, a logo on normal items of clothing, or breastfeeding can also cause the friction which results in this condition”.
Outside of the leisure sphere, there were two case study reports of ‘Diaper Doer’s Hand’ in a 1987 issue of the journal Clinical Rehabilitation by Dr. J.L. Cosgrove and colleagues:
“Three cases of stenosing tenosynovitis occurred three to six months postpartum. Childcare activities aggravated the symptoms of pain and swelling in both patients. In two cases, a specific method of carrying the child was implicated as the mechanism of injury. Although there was no evidence of generalized inflammatory arthritis, all patients had very low positive titres of anti-nuclear antibodies. While it is likely that tenosynovitis was caused by mechanical factors, the possibility of increased susceptibility to inflammatory disease in the postpartum period cannot be discounted. The patients were successfully treated with a low temperature plastic splint, superficial heat and gentle mobilization”.
All of these new syndromes lead to why I put this article together in the first place. I found this letter in the British Medical Journal by Dr. E.P. Hoare entitled ‘New Syndrome Syndrome’ that I found both funny and poignant:
“Your readers will be familiar with tennis elbow, brazier’s ague, and soap packer’s jig not to mention Achilles’ heel. More recently we have heard of Space Invader’s wrist, jogger’s nipples, and the ultimate futility of Cuber’s thumb. May I point out another occupational disease which I have noticed among patrons of the reading room medical journal correspondence column reader’s neck or, more succinctly, the new syndrome syndrome. Symptoms usually begin with muscular contraction of the eyebrows, hyperventilation, and involuntary utterances, which in severe cases can lead to coprolalia. These may be followed by drowsiness, disorientation, hysterical amblyopia, and double vision (of the deja vu variety). If untreated the condition can result in a chronic pain in the neck. Treatment is 200 ml of gin and tonic stat by mouth and complete rest; music can also be helpful. The long-term prognosis is poor, however, unless journal editors can be persuaded to ban further reports of occupational afflictions or at least print a health warning at the head of their correspondence columns”.
Dr. Mark Griffiths, Professor of Gambling Studies, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Behr, J.T. (1984). Pseudovideoma. Journal of Hand Surgery, 9(4), 613.
Cosgrove, J. L., Welch, D. A., Richardson, G. S., & Nicholas, J. J. (1987). Diaper doer’s hand: stenosing tenosynovitis in the postpartum period. Clinical Rehabilitation, 1(3), 219-223.
Gibofsky, A. (1983). Pac‐Man phalanx. Arthritis and Rheumatism, 26(1), 120.
Griffiths, M.D. (1995). Technological addictions. Clinical Psychology Forum, 76, 14-19.
Griffiths, M.D. (1995). Pop psychology and “aca-media”: A reply to Mitchell. The Psychologist: Bulletin of the British Psychological Society, 8, 537-538.
Griffiths, M.D. (2001). A moral obligation in aca-media? The Psychologist: Bulletin of the British Psychological Society, 14, 460.
Hite, P. R., Greene, K. A., Levy, D. I., & Jackimczyk, K. (1993). Injuries resulting from bungee-cord jumping. Annals of emergency medicine, 22(6), 1060-1063.
Hoare, E.P. (1982). Points: New syndrome syndrome. British Medical Journal, 285(6352), 1429.
Levit, F. (1977). Jogger’s nipples. New England Journal of Medicine, 297(20), 1127.
Maraz, A., Király, O., Urbán, R., Griffiths, M.D., Demetrovics, Z. (2015). Why do you dance? Development of the Dance Motivation Inventory (DMI). PLoS ONE, in press.
Martyn, J. B. (1983). Nurd knuckles. Canadian Medical Association Journal, 129(3), 228.
McCowan, T.C. (1981). Space Invader’s wrist. New England Journal of Medicine, 304,1368.
Osterman, A. L., Weinberg, P., & Miller, G. (1987). Joystick digit. Journal of the American Medical Association, 257(6), 782.
Powell, B. (1983). Bicyclist’s nipples. Journal of the American Medical Association, 249(18), 2457-2457.
Ramirez, B., Masella, P. A., Fiscina, B., Lala, V. R., & Edwards, M. D. (1984). Breaker’s neck. Journal of the American Medical Association, 252(24), 3366-3367.
Soe, G.B., Gersten, L. M., Wilkins, J., Patzakis, M. J., & Harvey, J.P. (1987). Infection associated with joystick mimicking a spider bite. Western Journal of Medicine, 146(6), 748.
Tomecki, K. J., & Mikesell, J. F. (1987). Rower’s rump. Journal of the American Academy of Dermatology, 16(4), 890-891.
Torre, P. R., Williams, G. G., Blackwell, T., & Davis, C. P. (1993). Bungee jumper’s foot drop peroneal nerve palsy caused by bungee cord jumping. Annals of emergency medicine, 22(11), 1766-1767.
Waugh, D. (1981). Cuber’s thumb. New England Journal of Medicine, 305, 768.
Blocked-in syndrome: Another look at Game Transfer Phenomena
Back in the early 1990s, I used to play the video game Tetris on my handheld Nintendo Game Boy. Although I say so myself, I was a really good player and I used to play for hours every day. When I went to bed I would see falling blocks as I closed my eyes. I often experienced the same thing when waking up. What I didn’t realise was that many other gamers experienced this too and that it had a name – ‘The Tetris Effect’. According to Wikipedia, “the Tetris effect occurs when people devote so much time and attention to an activity that it begins to pattern their thoughts, mental images, and dreams.”
In the late 1980s I started researching into the area of video game addiction. One of the papers I cited a lot in my early research concerning the side effects of excessive playing was a 1993 case study published in the Irish Journal of Psychological Medicine by Dr. Sean Spence. Dr. Spence reported the case of a female video game player who was diagnosed as suffering from persecutory delusions, exhibiting violent behaviour, and experiencing constant imaginary auditory hallucinations triggered by the music of the Super Mario Brothers video game. This case study and the Tetris effect are both examples of what I and my research colleague Angelica Ortiz de Gortari call ‘game transfer phenomena’ (GTP).
These phenomena tend to occur when video game players become so immersed in their gaming that when they stop playing, they sometimes transfer some of their virtual gaming experiences to the real world. These phenomena can occur both visually and aurally as well is in the form of unconscious bodily movements.
We have been researching GTP for a number of years and our first published study in 2011 made worldwide news. Some of the press coverage was both sensationalist (“Gamers can’t tell real world from fantasy, say researchers”) and misleading (“How video games blur real life boundaries and prompt thoughts of violent solutions to players’ problems”) and angered some of the gaming community. Our first published study in the International Journal of Cyber Behavior, Psychology and Learning was an exploratory study in which 42 gamers were interviewed. Although the sample was small, we reported that all our participants had, at some point, experienced some type of involuntary sensations, thoughts, actions and/or reflexes in relation to videogames when not playing them. For instance, one gamer reported witnessing a mathematics equation appearing in a bubble above his teacher’s head while another reported health bars hovering over football players from a rival team. However, this didn’t stop some of the press coverage being derogatory (“Unscientific survey of 42 gamers concludes video games interfere with perceptions of reality”).
Since then we have published three more studies from a self-selected dataset of over 1,600 gamers’ experiences (all of who had experienced some form of GTP) in various academic journals (International Journal of Human Computer Interaction; International Journal of Mental Health and Addiction; International Journal of Cyber Behavior, Psychology and Learning). Our findings have shown that some gamers (i) are unable to stop thinking about the game, (ii) expect that something from the game will happen in real life, (iii) display confusion between video game events and real life events, (iv) have impulses to perform something as in the video game, (v) have verbal outbursts, and (vi) experience voluntary and involuntary behaviours.
While some gamers qualify their experiences as funny, amusing, or even normal, others said they got surprised, felt worried, embarrassed and their experiences were a reason to quit playing. Based on our research so far, Game Transfer Phenomena appear to be commonplace among excessive gamers but the good news is that most of these phenomena are short-lasting, temporary, and appear to resolve of their own accord.
Despite instances of GTP elsewhere in the psychological and medical literature, we argue that there are important reasons for not using the ‘Tetris effect’ concept when studying game transfer effects. Among the most important are that: (i) the Tetris effect definition is very broad and does not emphasize the importance of the association between real life stimulus and video game elements as a trigger of some of the transfer experiences, (ii) it does not make a clear distinction between sensorial modalities in the game transfer experiences or talk about players’ experiences across sensorial modalities (e.g., hearing a sound and visualizing a video game element), and (iii) the name itself is inspired by a one specific stereotypical puzzle game (i.e., Tetris). This simple name indicates that it is repetition that triggers the transfer effects but there are other factors involved in game transfer experiences. Furthermore, modern video games use more than abstract shapes and offer more flexible scenarios compared to Tetris and similar games.
Our latest study that surveyed over 2,500 gamers is currently being analysed but preliminary results indicate that game transfer phenomena appear to be common among players – especially those that play heavily. It could be that some gamers are more susceptible than others to experience GTP. Although for many gamers the effects of these experiences appear to be short lived, our research also shows that some gamers experience them recurrently. More research is needed to understand the cognitive and psychological implications of GTP. Our studies to date show there is a need to investigate neural adaptations and after-effects induced by video game playing as a way of encouraging healthy and safe video game playing.
Note: This blog is an extended version of an article first published in The Conversation
Dr. Mark Griffiths, Professor of Gambling Studies, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Gackenbach, J.I (2008). Video game play and consciouness development: A transpersonal perspective. Journal of Transpersonal Psychology, 40(1), 60-87.
Griffiths, M. D., Kuss, D.J., & Ortiz de Gortari, A. (2013). Videogames as therapy: A review of the medical and psychological literature. In I. M. Miranda & M. M. Cruz-Cunha (Eds.), Handbook of research on ICTs for healthcare and social services: Developments and applications (pp.43-68). Pennsylvania: IGI Global.
Ortiz de Gotari, A., Aronnson, K. & Griffiths, M.D. (2011). Game Transfer Phenomena in video game playing: A qualitative interview study. International Journal of Cyber Behavior, Psychology and Learning, 1(3), 15-33.
Ortiz de Gortari, A.B. & Griffiths, M.D. (2012). An introduction to Game Transfer Phenomena in video game playing. In J. Gackenbach (Ed.), Video Game Play and Consciousness (pp.223-250). Nova Science
Ortiz de Gortari, A.B. & Griffiths, M.D. (2014). Altered visual perception in Game Transfer Phenomena: An empirical self-report study. International Journal of Human-Computer Interaction, 30, 95-105.
Ortiz de Gortari, A.B. & Griffiths, M.D. (2014). Auditory experiences in Game Transfer Phenomena: An empirical self-report study. International Journal of Cyber Behavior, Psychology and Learning, 4(1), 59-75.
Ortiz de Gortari, A.B. & Griffiths, M.D. (2014). Automatic mental processes, automatic actions and behaviours in Game Transfer Phenomena: An empirical self-report study using online forum data. International Journal of Mental Health and Addiction, 12, 432-452.
Parfitt, B. (2011). Metro “can’t tell real world from fantasy”. MCV. September 21. Located at: http://www.mcvuk.com/news/read/metro-can-t-tell-real-world-from-fantasy/085065
Purchase, R. (2011). Prof clarifies Game Transfer Phenomena. Eurogamer.net. September 21. Located at: http://www.eurogamer.net/articles/2011-09-21-game-transfer-phenomena-authors-defence
Spence, S.A. (1993). Nintendo hallucinations: A new phenomenological entity. Irish Journal of Psychological Medicine, 10, 98-99.
The Tetris Effect. Located at: http://en.wikipedia.org/wiki/Tetris_effect
Coming a part of the themes: The psychology of familiarity in gambling
Have you seen slot machines featuring Spiderman? Or the ones based on the Monopoly board game? Or the slots that have pictures of Lara Croft from the Tomb Raider video game? Most gaming operators will appreciate that all of these images have a strong brand presence, and that it is one of the main reasons for themed games. However, a more basic marketing tactic is being used here – the psychology of familiarity. This is used throughout the gaming industry but is most common on slot machines, online games, and scratchcards. For instance, Camelot’s scratchcards in the UK have featured film tie-ins (e.g., James Bond, Pirates of the Caribbean, Star Wars), and popular games (e.g., Connect Four).
But this wasn’t always the case. Back in the late 1980s I did some research on the names that gaming designers and operators gave their slot machines. One of the more interesting findings I reported in one of my academic papers was that over 50% of all machine names that I came across in amusement arcades had some reference to money on them (such as ‘Cashpoint’, ‘Cashline’, ‘Action Bank’, Piggy Bank’, ‘Money Belt’ etc.). Psychologically, all of these machine names gave the impression that this was where a player could get money from – not where they would lose it! Other categories of machine names included those with some reference to skill on them (‘Fruitskill’, ‘Skillchance’) suggesting that machine playing was a skillful activity and that gamblers could perhaps beat the machine. Other machines had what I called “acoustically attractive” names (Nifty Fifty, Naughty But Nice) or puns (Reel Fun, Reel Money). Since making these observations, I have always been interested in the subtle techniques that the gaming industry uses in getting the punter to play on their products. The psychology of gambling – or rather the psychology of gambling marketing – has come a long way in the last decade.
As I’ve already said, one of the techniques that the gaming industry uses (whether they realise it or not) is the psychology of familiarity. Gaming operators and marketers have realised that one weapon in their marketing armory is to design products which appear familiar before a player has ever even played on them – something that can partly be achieved through the name or theme of the slot machine. The examples I gave above showed that the names of slot machines appear to be important in impression formation. It is highly unlikely that the names of slot machines have any influence on gambling behaviour per se. However, when tied in with recent research on the psychology of familiarity, the names of machines do seem to be critically important – particularly in terms of gambling acquisition (that is, getting people to gamble in the first place).
Nowadays, slot machines are often named after a famous person (the Elvis Presley machines appear very popular in one of my local casinos), place, event, video game, board game, television show or film. Not only is this something that is familiar to the gambler but may also be something that the potential gamblers might like or affiliate themselves with (such as James Bond). This is different from a simple naming effect in that the machine’s theme may encompass the whole play of the machine, including its features, the sound effects (e.g., the theme tune to popular television programmes like Coronation Street or Eastenders), and light/colour effects. By using well-known and common themes, gamblers may be more likely to spend time and money playing them.
Some of the most popular UK slot machines are those that feature The Simpsons. There are many possible reasons why a gambler might be more likely to play on a Simpsons’ machine. The Simpsons have mass appeal and popularity across all ages and across gender. The machines are celebrity-endorsed and players may place trust in a ‘quality’ brand like The Simpsons. Gamblers may also hope that knowledge of the characters will help in the playing of the game. On a basic level, it might simply be that the game play of The Simpsons is more exciting, and that the sound effects and features are novel, cute and/or more humorous than other machines. There are many cases similar to this one where it could be speculated that the slot machine becomes so much more inducing because it represents something that is familiar and/or special to the gambler.
Familiarity is a very important psychological aspect of why themed slot machines have been more prominent over the last decade. Familiar themes have the capacity to induce a ‘psycho-structural interaction’ between the gambler and the gambling activity. This is where the gambler’s own psychology interacts with the machine’s structural characteristics and produces different consequences for each person depending upon what the feature means to them personally. If the themes are increasingly familiar, a gambler might be more likely to persevere with the complexities of a machine. Gamblers may find it more enjoyable because they can easily interact with recognizable images they experience. Therefore, the use of familiar themes may have a very persuasive effect, leading to an increase in the number of people using them, and the money they spend. Whilst there are many other aspects that influence an individual’s decision to gamble, the possible persuasive nature of the themes should not be underestimated.
As you may have already gathered, there is a strong overlap between the psychology of familiarity, branding, and the psychology of persuasion. In very simple terms, a gambler must be exposed to the product and be aware of its presence before they can even make the decision to gamble. This is relatively easy to achieve given the ubiquity of slot machines and the fact that current machines will use any number of techniques to grab a potential player’s attention. These include television or film theme tunes, bright flashing lights, and/or pictures or voices of celebrities. Once a gambler’s attention has been gained, the product must be likeable and familiar enough for them to think about gambling and wanting to interact with the machine further. Immediately familiar images and sounds are likely to lead to a much quicker decision to gamble. All which goes to show – the gaming industry knows what it is doing!
Dr. Mark Griffiths, Professor of Gambling Studies, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Griffiths, M.D. (1993). Fruit machine gambling: The importance of structural characteristics. Journal of Gambling Studies, 9, 101-120.
Griffiths, M.D. (2007). Brand psychology: Social acceptability and familiarity that breeds trust and loyalty.Casino and Gaming International, 3(3), 69-72.
Griffiths, M.D. & Dunbar, D. (1997). The role of familiarity in fruit machine gambling. Society for the Study of Gambling Newsletter, 29, 15-20.
Griffiths, M.D. & Parke, J. (2003). The environmental psychology of gambling. In G. Reith (Ed.), Gambling: Who wins? Who Loses? (pp. 277-292).New York: Prometheus Books.
King, D.L., Delfabbro, P.H. & Griffiths, M.D. (2010). Video game structural characteristics: A new psychological taxonomy. International Journal of Mental Health and Addiction, 8, 90-106.
Parke, J. & Griffiths, M.D. (2006). The psychology of the fruit machine: The role of structural characteristics (revisited). International Journal of Mental Health and Addiction, 4, 151-179.
Parke, J. & Griffiths, M.D. (2007). The role of structural characteristics in gambling. In G. Smith, D. Hodgins & R. Williams (Eds.), Research and Measurement Issues in Gambling Studies (pp.211-243). New York: Elsevier.
Wood, R.T.A., Griffiths, M.D., Chappell, D. & Davies, M.N.O. (2004). The structural characteristics of video games: A psycho-structural analysis. CyberPsychology and Behavior, 7, 1-10.
