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Hearing aid: A brief look at ‘the world’s most addictive sounds’
Throughout my career I’ve carried out quite a lot of research into the marketing and advertising of gambling and the way in which some gambling operators use psychology to exploit our senses to maximize profit. Connected to this, I’ve also published a number of papers that have examined the role of sound (and particularly music) can influence the way in which individuals gamble (see my previous blog on this and ‘Further reading’ below).
The reason I mention this was that I recently came across an online article by Fast Company entitled ‘The 10 most addictive sounds in the world’ based on some market research carried out by Martin Lindstrom, the Danish ‘neuromarketeer’, author of the book Buyology – Truth and Lies About Why We Buy (I do love a good pun). Lindstrom is known for using neuroscientific techniques to help commercial operators better understand their clientele. One of his collaborations was with Elias Arts (a sound and music design company) who joined forces to examine the world’s most ‘addictive sounds’ in what an article in The Village Voice dubbed a “neuromarketing experiment”.
Obviously, my interest was piqued when I saw the use of the word ‘addictive’ but their working definition of ‘addictive’ had nothing to do with individuals being addicted to sounds but simply referred to an individual’s response to specific sounds. (Even with this explanation, I still can’t see why the word ‘addictive’ was used but its’ use probably guarantees more people – like myself – will want to read about the study). Lindstrom told the media that:
“We have all those top 10s of everything, but most top 10s are based on the visual sense. What we realized in another study is the most prominent sense we have [when we see a commercial] is not the sense of sight or smell, but the sense of sound”.
As far as I can tell, the study Lindstrom carried out has not been formally published in a peer reviewed journal (although he has published academic papers). The study was described in the international media as involving 50 participants and the research team monitored their brainwave, pupil, and facial muscle activity while listening to 50 different everyday sounds (both man-made ‘branded’ sounds and those ‘non-branded’ sounds that occur naturally). Lindstrom concluded that the most ‘addictive sounds’ weren’t necessarily the non-branded sounds of nature because some of the commercial man-made branded sounds (described as “beeps, jingles and ditties”) were more ‘addictive’ than a number of familiar sounds found in everyday life.
Overall, sound of a baby giggling was ranked as the most ‘addictive sound’ (although I’ve not seen the specific methodology employed to ascertain how being the top ‘addictive sound’ was actually assessed. Apparently Lindstrom examined the “dimension of the responses” and the “contrast and balance of all three [brainwave, pupil and muscle] factors” – although he did admit that such factors can lead to both positive and negative reactions). The second and third spots were Intel’s computer startup chime and the sound of a vibrating mobile phone. Other top non-branded sounds were the sound of a sizzling steak and the lighting of a cigarette being inhaled. Lindstrom claimed that the participants “weren’t responding to the structures of the sounds, but what they mean in a greater social context”. In relation to what makes a sound ‘addictive’, Lindstrom did at least make one reference to a classic sign of addiction (i.e., craving):
“It’s not the sound itself, but the consequence of the sound. A laughing (or crying) baby elicits a maternal protection mechanism, a buzzing cell phone prompts a pick-up, a sizzling steak means a solid meal is on the way. For advertisers and consumers, the research indicates a whole new battleground of multi-sensory advertising. Sometimes the sound from one category generates a craving in another category. For example, given the links between tobacco and beverages, the sound of a cigarette being lit could be used in an ad for alcohol. Although sound is more intuitive for people, the field is still quite young. It will be a long time before it will be so prominent”.
In a story for ABC News, other academics were asked for their thoughts on Lindstrom’s study. One American ‘auditory neuroscientist, Professor Barbara Shinn-Cunningham (actually Professor of Biomedical Engineering at Boston University) said that:
“Although the sounds identified by the study are extremely meaningful, with the exception of the giggling baby, most are not inherently addictive. They’re identifiable. They brain responds to repetition. Our brains are good at picking out patterns that repeat. We’ve evolved to do that. If I chose an arbitrary sound, as long as it was clear and distinctive, and then played it 50 times a day for the next five years (as many of the branded sounds have been), it would become attention-grabbing. I don’t think [the sounds on the list are] so much addictive because of their acoustic properties, but because of their ubiquity. There is neurophysiological evidence showing that brain is hardwired to notice certain kinds of sounds. For example, the abrupt, jarring sound of a slamming door could prompt cells in a person’s brain stem to fire even before that person was conscious of it. For early humans, that kind of sound could have meant it’s time to run for the hills. [Also] studies have demonstrated the existence of a so-called ‘cocktail party effect’. At a party, if you hear your name in the background, even if you’re not paying attention, that’s something that will draw your attention involuntarily. Your brain is so exposed to your name and it’s tremendously important to you, so it encodes that so you respond to it”
According to Lindstrom’s research, the most ‘addictive sounds’ in the world (although they are arguably US-centric to say the least) are: (1) baby giggle, (2) Intel chime, (3) vibrating phone, (4) ATM/cash register, (5) National Geographic theme tune, (6) MTV theme tune, (7) T-Mobile ringtone, (8) McDonald’s jingle, (9) ‘Star Spangled Banner’ (tune), and (10) State Farm jingle.
The Fast Company article also noted that:
“Sound is immensely powerful. And yet 83% of all the advertising communication we’re exposed to daily (bearing in mind that we will see two million TV commercials in a single lifetime) focuses, almost exclusively, on the sense of sight. That leaves just 17% for the remaining four senses. Think about how much we rely on sound. It confirms a connection when dialing or texting on cell phones and alerts us to emergencies. When the sound was removed from slot machines in Las Vegas, revenue fell by 24%. Experiments undertaken in restaurants show that when slow music (slower than the rhythm of a heartbeat) is played, we eat slower–and we eat more!”.
These types of findings suggest that ‘audio branding’ is likely to be an increasing topic of academic research given that every company wants an edge in selling their product. While I am totally unconvinced that the word ‘addictive’ should be used in this type of research, that’s not to say that sound doesn’t have an influence in the development of addictive behaviour more generally. It looks like a case of watch (or should that be listen?) to this space.
Dr. Mark Griffiths, Professor of Behavioural Addiction, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Bark Soho (2016). 3 of the most addictive sounds in the world. October 16. Located at: http://www.barksoho.co.uk/blog/3-of-the-most-addictive-sounds-in-the-world/
Dixon, L., Trigg, R. & Griffiths, M. (2007). An empirical investigation of music and gambling behaviour. International Gambling Studies, 7, (3), 315-326.
Edroso, R. (2010). “Most addictive” sounds mostly jingles, machine noises. The Village Voice, February 22. located at: https://www.villagevoice.com/2010/02/22/most-addictive-sounds-mostly-jingles-machine-noises/
Fast Company (2010). The 10 most addictive sounds in the world. February 22. Located at: https://www.fastcompany.com/1555211/10-most-addictive-sounds-world
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.
Griffiths, M.D. & Parke, J. (2005). The psychology of music in gambling environments: an observational research note. Journal of Gambling Issues, 13.
Heussner, K.M. (2010). The world’s 10 most addictive sounds. ABC News, February 24. Located at: https://abcnews.go.com/Technology/worlds-10-addictive-sounds/story?id=9923506
Lindstrom, M. (2008). Buyology: Truth and Lies About Why We Buy. New York: Doubleday
Parke, J. & Griffiths, M.D. (2006). The psychology of the fruit machine: The role of structural characteristics re-visited. 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.
Spenwyn, J., Barrett, D.K.R. & Griffiths, M.D. (2010). The role of lights and music in gambling behavior: An empirical pilot study. International Journal of Mental Health and Addiction, 8, 107-118.
Word up: The phonetics of branding in marketing
Although I have published a number of papers on the psychology of gambling advertising, branding, and marketing, I cannot claim to be in expert in the more general area of branding psychology. However, I feel more knowledgeable about the area having just read a fascinating paper by Sascha Topolinski, Michael Zürn and Iris Schneider recently published in the journal Frontiers in Psychology. Their paper examines “the biomechanical connection between articulation and ingestion-related mouth movements to introduce a novel psychological principle of brand name design”. Now I’m sure a lot of you will be none-the-wiser from that description but keep with me because I think what they have done is ingenious. Before I get to the heart of their research findings, I ought to add that I also learned a lot in their paper’s introduction. For instance:
- Repeated exposure to brands increase positive attitudes and the likelihood of eventual brand choice, and also increases the fluency of a brand name.
- Repetition-induced high fluency due to advertising depends upon subtle mouth exercises. Activities that stop this happening (such as eating popcorn while watching an advert in the cinema) inhibit the effect of the advertising.
- Easier to pronounce brand names (unsurprisingly) increases fluency. The easier the brand name is to pronounce, the more positive individual’s attitudes are towards the brand.
- Consumer responses to brands can be influenced by how the name of brand sounds (so-called ‘phonetic symbolism’). In these instances “the sound of a word conveys certain characteristics of the denoted object or product, such as size, color, or touch. For instance, some vowels sound high (for instance [i] as in SWEET), and other vowels sound low, (for instance [u] as in LOOP). High vowels are associated with little, fast, or light objects, while low vowels are associated with large, steady, or heavy objects”. Research has shown that fictitious brand names for hammers (that are heavy items) are preferred by consumers when they contain low vowels whereas fictitious brand names for knives (that are light items) are preferred by consumers when they contain high vowels.
Based on these research findings, Dr. Topolinski and colleagues reached the conclusion that in relation to brand names, consumer choice can be influenced by word sounds and articulation fluency. However, their new research studies (seven studies in one paper) went beyond this by examining consumer behaviour towards brands based on the muscle movements while saying the name of the brand. The studies constructed brand names for diverse products that are spoken inwardly (from the front to the rear of the mouth, such as the fictitious brand name ‘BODIKA’), or are spoken outwardly (from the rear to the front, such as the brand name ‘KODIBA’). Here is the authors’ easy-to-understand explanation:
‘[It] is possible to construe words that feature consonant sequences that wander either from the front to the rear (inward) or from the rear to the front (outward) of the mouth. Take, for instance, the three consonants K, D, and P. Arranged in the word KADAP, first the rear back of the tongue is pressed against the soft palate to generate K, then the tip of the tongue is pressed against the soft palate to generate D, and then the lips are pressed together to generate P. These muscle tensions thus wander from the rear to the front of the mouth, this is, outward. Reversely, arranged in the word PADAK, first the lips are pressed together, then the tip of the tongue touches the soft palate, and then the rear back of the tongue touches the soft palate. These muscle tensions wander from the front to the rear, of the mouth, that is, inward. Combining such articulatory patterns with the muscle patterns of ingestion and expectoration, it is obvious that inward consonantal wanderings (PADAK) resemble the muscular dynamics during ingestion, and outward consonantal wanderings (KADAP) resemble the muscular dynamics during expectoration…Since ingestion is positively associated, and expectoration is negatively associated…consonantal wanderings may feel positive and outward wanderings may feel negative”.
The seven studies that were carried out (comprising a total of 1,261 participants) compared the fictitious inward speaking brand name (e.g., ‘BODIKA’) with the fictitious outward speaking brand name (e.g., ‘KODIBA’). The results of the seven studies (using a variety of different methodologies including laboratory experiments and surveys, and including participants that spoke different languages [German and English]) were very revealing. In summary, the participants (i) preferred the inward name product to the outward name, and (ii) reported higher likelihood to purchase the inward named product, and (iii) reported higher willingness-to-pay for the inward named brand (participants said they would pay 4-13% more for the inward name brand). The same effects were found in both English and German language. The authors concluded:
“[The] present approach exploits the biomechanical connection between articulation and ingestion to introduce a novel psychological principle for brand name design. Brands for which the consonantal articulation spots wander inwards in the mouth compared to outwards are preferred, elicit higher purchase intentions, and even trigger higher willingness-to-pay with a substantial possible monetary gain”.
The paper did make me wonder about implications for brand names in the gambling industry. All things being equal, it suggests that gamblers may prefer to spend their money with companies such as PKR and Bet 365 than Corals and 888.
Dr Mark Griffiths, Professor of Gambling Studies, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Baker, W. E. (1999). When can affective conditioning and mere exposure directly influence brand choice. Journal of Advertising, 28, 31–46.
Griffiths, M.D. (1997). Children and gambling: The effect of television coverage and advertising. Media Education Journal, 22, 25-27.
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. (2005). Does advertising of gambling increase gambling addiction? International Journal of Mental Health and Addiction, 3(2), 15-25.
Griffiths, M.D. (2013). Responsible marketing and advertising of gambling. i-Gaming Business Affiliate, August/September, 50.
Hanss, D., Mentzoni, R.A., Griffiths, M.D., & Pallesen, S. (2015). The impact of gambling advertising: Problem gamblers report stronger impacts on involvement, knowledge, and awareness than recreational gamblers. Psychology of Addictive Behaviors, 29, 483-491.
Janiszewski, C. & Meyvis, T. (2001). Effects of brand logo complexity, repetition, and spacing on processing fluency and judgment. Journal of Consumer Research, 28, 18–32.
Laham, S.M., Koval, P., & Alter, A. L. (2012). The name-pronunciation effect: why people like Mr. Smith more than Mr. Colquhoun. Journal of Experimantal Social Psychology, 48, 752–756.
Lodish, L. M., Abraham, M., Kalmenson, S., Livelsberger, J., Lubetkin, B., Richardson, B., et al. (1995). How TV advertising works: a meta-analysis of 389 real world split cable TV advertising experiments. Journal of Marketing Research, 32, 125–139.
Lowrey, T. M., and Shrum, L. J. (2007). Phonetic symbolism and brand name preference. Journal of Consumer Research, 34, 406–414.
Rozin, P. (1999). Preadaptation and the puzzles and properties of pleasure. In D. Kahneman, E. Diener, & N. Schwarz (Eds.), Well-being: The Foundations of Hedonic Psychology (pp.109-133). New York, NY: Russell-Sage).
Song, H. & Schwarz, N. (2009). If it’s difficult-to-pronounce, it must be risky: fluency, familiarity, and risk perception. Psychological Science, 20, 135–138.
Topolinski, S., Lindner, S. & Freudenberg, A. (2014a). Popcorn in the cinema: oral interference sabotages advertising effects. Journal of Consumer Psychology, 24, 169–176.
Topolinski, S., Zürn, M. & Schneider, I.K. (2015) What’s in and what’s out in branding? A novel articulation effect for brand names. Frontiers in Psychology 6, 585. doi: 10.3389/fpsyg.2015.00585
Way up the cost: Will the increased price of National Lottery tickets affect sales?
The following blog is based on a short article that I wrote for Nottingham Trent University’s Expert Opinion column published earlier this year (January 29, 2013) and is a written version of many of the comments I made in national and local BBC radio interviews yesterday.
This week Camelot Plc increased the price of a Lotto ticket from £1 to £2 – but will this 100% price increase have any effect on whether people play the bi-weekly game? My own view is that although there may be a dip in overall sales when the price of the tickets first increases, over time, sales are likely to return to pre-price increase levels.
The price of buying a lottery ticket is just one of many inter-connected structural characteristics that help determine whether potential players will play the lottery. Other structural characteristics in gambling activities include the size of the jackpot, the number of smaller prizes, the probability of winning the jackpot and / or smaller prizes, the speed of the game, how quickly players receive their winnings, the ease of playing the game, whether the game is chance-based or requires some skill, the number of chances to gamble on a single event, etc.
The chance of winning the bi-weekly lottery is an incredible one in 14 million. But is playing Lotto a tribute to public innumeracy and totally irrational? Not necessarily. Lotto offers a low-cost chance of winning a very large life-changing amount of money. Many psychologists would argue that playing Lotto is entirely rational behaviour given the small cost involved. Basically, it’s a small cost for millions of people buying hope. More importantly, we know that most players don’t think about the actual probability of winning but concentrate on the amount that could be won (i.e., the jackpot size). Players may also rationalize that the cost of a ticket is still cheaper than buying a pint of lager in a pub or a coffee atStarbucks.
Jackpot size is one of the most important factors in whether people play the lotto. The fact that the ticket price is doubling doesn’t take away the fact that there will still be an enormous jackpot. Additionally, to soften the blow of the increased price, the amount that can be won for matching three numbers will increase from £10 to £25. This again is likely to help sales maintenance. And if people do feel that £2 is too much for a single ticket, there are plenty of other games in the national lottery portfolio to choose from.
Another factor that is important in lottery profitability for the operators is that we tend to overestimate positive outcomes and underestimate negative ones. If someone is told they have a one in 14 million chance of being killed that day they would hardly give it a second thought because the chances are tiny. Given the same probability of winning Lotto people suddenly become over-optimistic (“It could be you!”).
The media also plays a part. By providing widespread coverage for the few huge winners, it helps us forget the millions of people who lost! Finally, for regular players who choose the same numbers every week, they become ‘entrapped’ fearing that the one week they don’t play will be the week their numbers will come up. Players who have picked the same numbers for years are still likely to play despite the price increase for the same reason.
The bottom line is that Camelot will have done lots of market research to determine whether players will be prepared to pay more money to play Lotto. Major decisions about pricing are key to future success and increased profits. If people stop playing Lotto in their masses, a return to a lower price will be inevitable. However, my guess is that most current Lotto players will continue to play a game as the thought of winning millions of pounds outweighs the price increase.
Dr Mark Griffiths, Professor of Gambling Studies, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Arkes, H.R. & Blumer, C. (1985). The psychology of sunk cost. Organizational Behavior and Human Decision Processes, 35, 124-140.
Griffiths, M.D. (1997). The National Lottery and instant scratchcards: A psychological perspective. The Psychologist: The Bulletin of the British Psychological Society, 10, 26-29.
Griffiths, M.D. (1997). Selling hope: The psychology of the National Lottery. Psychology Review, 4, 26-30..
Griffiths, M.D. (2008). Problem gambling and European lotteries. In M. Viren (Ed.), Gaming in New Market Environment. pp. 126-159. New York: Macmillan Palgrave.
Griffiths, M.D. (2010). The effect of winning large jackpots on human behaviour. Casino and Gaming International, 6(4), 77-80.
Griffiths, M.D. (2011). Gambling, luck and superstition: A brief psychological overview. Casino and Gaming International, 7(2), 75-80.
Griffiths, M.D. & Wood, R.T.A. (2001). The psychology of lottery gambling. International Gambling Studies, 1, 27-44.
Kahneman, D. & Tversky, A. (1973). Availability: A heuristic for judging frequency and probability. Cognitive Psychology, 5, 207-233.
Langer, E.J. (1975). The illusion of control. Journal of Personality and Social Psychology, 32, 311-328.
Langer, E.J. & Roth, J. (1975). The effect of sequence outcome in a chance task on the illusion of control. Journal of Personality and Social Psychology, 32, 951-955.
Tversky, A. & Kahneman, D. (1971). Belief in the law of small numbers. Psychological Bulletin, 76, 105-110.
Walker, M.B. (1992). The Psychology of Gambling. Pergamon, Oxford.
Wagenaar, W. (1988). Paradoxes of Gambling Behaviour. Erlbaum, London.
Wood, R.T.A. & Griffiths, M.D. (2004). Adolescent lottery and scratchcard players: Do their attitudes influence their gambling behaviour? Journal of Adolescence, 27, 467-475.
Blame it on the fame? The role of celebrity endorsement in gambling advertising
Have any of you reading this ever visited an online poker site because of a celebrity endorsement? Would the presence of Ben Affleck or James Woods make you more likely to play poker? Commercial gambling has only relatively recently got in on the celebrity endorsement bandwagon mainly because gambling advertising has always been very restricted. When a poker company uses a celebrity endorser, they are signing up an image that is itself a gamble. At the very least, gaming companies should get what they pay for but it can all go horribly wrong. When a purple-bearded Billy Connolly was used to promote the National Lottery in 2002/2003, sales decreased. The adverts had high recall by the public but were hated by a large proportion of the British public who found Connolly highly irritating.
This is all goes to show that any gaming company wanting to use celebrity endorsement as part of its marketing drive has to carefully evaluate a celebrity’s image and reputation. Steps need to be taken to make sure the celebrity’s image and reputation matches the needs of the company. Sales can take a tumble especially if the celebrity used does something that compromises the company’s image. For instance, Vic Reeves drink-driving conviction wasn’t very good for the car insurance company he was promoting! However, in most situations, the relationship between the company and the celebrity will be mutually beneficial. The company receives all of the perks associated with the celebrity such as publicity, positive connotation, recognition, respect and trust. The celebrity – at the very least – benefits financially.
The advertising industry claims that brand recognition, recall and awareness are the most important outcomes of successful marketing campaigns. This, they believe, will result in greater sales and increased revenue. However, as with the Billy Connolly example above, this isn’t always the case. Celebrity endorsement is perhaps even more important in online commercial activities like playing Internet poker where identity, trust and reliability equate to potential punters. As a consequence, many online commercial enterprises appear to opt for short-term, high impact celebrity endorsement and ‘buzz marketing’ rather than investing for the long term. These types of marketing tend to create an instant image and reputation but may not necessarily be good for the company’s longevity. To be market leaders amid the competition, online gaming operators will need to couple strategic marketing with solid brand management.
Interestingly, a survey carried out by Marketing UK asked marketers from a sample of the top 1000 British companies which techniques they thought were the most successful in increasing sales and at building long-term relationships with customers. It found that celebrity endorsements ranked last, beneath things like loyalty schemes, sales promotions, and general display advertising. However, it doesn’t make sense to isolate celebrity endorsements, because they are just one of many marketing elements that are used in a successful campaign. What’s more, if marketers didn’t believe celebrities help in generating long-term sales and profits, they wouldn’t keep paying the large fees they command.
While the jury is out on whether celebrity endorsement is a sales winner, one question that has yet to be answered through research is, what type of gambler does a celebrity endorsement impress and/or influence in their decision play? Is it the novices, long-standing players, or both? Maybe different types of celebrities appeal to different clientele. For me, the most interesting development of the celebrity endorsement culture is how the big poker tournament winners have now become celebrities in their own right. For instance, the star after-dinner speaker at an academic gambling conference I was at in Lake Tahoe was World Series of Poker veteran Howard Lederer. This type of celebrity endorsement may be more appealing to players. The fact that someone has become a celebrity through skill and talent in an activity that gamblers are already positively predisposed towards suggests they will want to have more of a psychological association with these celebrities than those the celebrities who just happen to play poker as a hobby. Judging by the front covers of magazines like Inside Poker, the editors clearly believe that it is the big poker winners that sell the magazine rather than Hollywood A-listers or scantily dressed women.
Celebrity endorsements also tap into the psychology of ‘intrinsic association’. This is the degree to which the gambling activity is positively associated with other interests, people and/or attractions. Intrinsic association also taps into the psychology of familiarity and help explain why so may UK slot machines feature themes relating to television shows, films, popular board games, video games or celebrities. It makes punters feel they know something about the product before they have even played it.
Gaming companies have to ask themselves how much they are willing to gamble on celebrity endorsement in trying to carve out a niche in the market. Companies have got to be clear that they are targeting the right product with the right celebrity with the right message. It can be a long hard slog to shape an image or reputation but it can take just a few seconds of celebrity madness to destroy it.
Dr Mark Griffiths, Professor of Gambling Studies, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Binde, P. (2007). Selling dreams – causing nightmares? On gambling advertising and problem gambling. Journal of Gambling Issues, 20, 167-191.
Griffiths, M.D. (2005). Does advertising of gambling increase gambling addiction? International Journal of Mental Health and Addiction, 3(2), 15-25.
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. (2010). Celebrity endorsement and online gambling: Ten golden rules. i-Gaming Business Affiliate, June/July, p.64.
Griffiths, M.D. (2010). Media and advertising influences on adolescent risk behaviour. Education and Health, 28(1), 2-5.
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.
Griffiths, M.D., Parke, J., Wood, R.T.A. & Rigbye, J. (2010). Online poker gambling in university students: Further findings from an online survey. International Journal of Mental Health and Addiction, 8, 82-89.
Wood, R.T.A., Griffiths, M.D. & Parke, J. (2007). The acquisition, development, and maintenance of online poker playing in a student sample. CyberPsychology and Behavior, 10, 354-361.
Zangeneh, M., Griffiths, M.D. & Parke, J. (2008). The marketing of gambling. In Zangeneh, M., Blaszczynski, A., and Turner, N. (Eds.), In The Pursuit Of Winning. pp. 135-153. New York: Springer.