Category Archives: Sex
More mass debating: Compulsive sexual behaviour and the internet
The issue of sex addiction as a behavioural addiction has been hotly debated over the last decade. A recent contribution to this debate is a review by Shane Kraus and his colleagues in the latest issue of the journal Addiction that examined the empirical evidence base for classifying compulsive sexual behaviour (CSB) as a behavioural (i.e., non-substance) addiction. The review raised many important issues and highlighted many of the problems in the area including the problems in defining CSB, and the lack of robust data from many different perspectives (epidemiological, longitudinal, neuropsychological, neurobiological, genetic, etc.).
As my regular blog readers will know, I have carried out empirical research into a wide variety of different behavioural addictions (gambling, video gaming, internet use, exercise, sex, work, etc.) and have argued that some types of problematic sexual behaviour can be classed as sex addiction depending upon the definition of addiction used. I was invited by the editors of Addiction to write a commentary on the review and this has just been published in the same issue as the paper by Kraus and colleagues. This blog briefly looks at the issues in that review that I highlighted in my commentary.
For instance, there are a number of areas in Kraus et al.’s paper that were briefly mentioned without any critical evaluation. For instance, in the short section on co-occurring psychopathology and CSB, reference was made to studies claiming that 4%-20% of those with CSB also display disordered gambling behaviour. I pointed out that a very comprehensive review that I published with Dr. Steve Sussman and Nadra Lisha (in the journal Evaluation and the Health Professions) examining 11 different potentially addictive behaviours also highlighted studies claiming that sex addiction could co-occur with exercise addiction (8%-12%), work addiction (28%-34%), and shopping addiction (5%-31%). While it is entirely possible for an individual to be addicted to (say) cocaine and sex concurrently (because both behaviours can be carried out simultaneously), there is little face validity that an individual could have two or more co-occurring behavioural addictions because genuine behavioural addictions consume large amounts of time every single day. My own view is that it is almost impossible for someone to be genuinely addicted to (for example) both work and sex (unless the person’s work was as an actor/actress in the pornographic film industry).
The paper by Kraus et al also made a number of references to “excessive/problematic sexual behavior” and appeared to make the assumption that ‘excessive’ behaviour is bad (i.e., problematic). While I agree that CSB is typically excessive, excessive sex in itself is not necessarily problematic. Preoccupation with any behaviour in relation to addiction obviously needs to take into account the context of the behaviour, as the context is far more important in defining addictive behaviour than the amount of the activity undertaken. As I have constantly argued, the fundamental difference between a healthy excessive enthusiasms and addictions is that healthy excessive enthusiasms add to life whereas addictions take away from them.
The paper also appeared to have an underlying assumption that empirical research from a neurobiological and genetic perspective should be treated more seriously than that from a psychological perspective. Whether problematic sexual behaviour is described as CSB, sex addiction and/or hypersexual disorder, there are thousands of psychological therapists around the world that treat such disorders. Consequently, clinical evidence from those that help and treat such individuals should be given greater credence by the psychiatric community.
Arguably the most important development in the field of CSB and sex addiction is how the internet is changing and facilitating CSB. This was not even mentioned until the concluding paragraph yet research into online sex addiction (while comprising a small empirical base) has existed since the late 1990s including sample sizes of up to almost 10,000 individuals. In fact, there have been a number of recent reviews of the empirical data concerning online sex addiction including its treatment including ones by myself in journals such as Addiction Research and Theory (in 2012) and Current Addiction Reports (in 2015). My review papers specifically outlined the many specific features of the Internet that may facilitate and stimulate addictive tendencies in relation to sexual behaviour (accessibility, affordability, anonymity, convenience, escape, disinhibition, etc.). The internet may also be facilitating behaviours that an individual would never imagine doing offline such as cybersexual stalking.
Finally, there is also the issue of why Internet Gaming Disorder was included in the DSM-5 (in Section 3 – ‘Emerging measures and models’) but sex addiction/hypersexual disorder was not, even though the empirical base for sex addiction is arguably on a par with IGD. One of the reasons might be that the term ‘sex addiction’ is often used (and arguably misused) by high profile celebrities as an excuse to justify their infidelity (e.g., Tiger Woods, Michael Douglas, David Duchovny, Russell Brand), and is little more than a ‘functional attribution’. For instance, the golfer Tiger Woods claimed an addiction to sex after his wife found out that he had many sexual relationships during their marriage. If his wife had never found out, I doubt whether Woods would have claimed he was addicted to sex. I would argue that many celebrities are in a position where they are bombarded with sexual advances from other individuals and have succumbed. But how many people would not do the same thing if they had the opportunity? Sex only becomes a problem (and is pathologised) when the person is found to have been unfaithful. Such examples arguably give sex addiction a ‘bad name’, and provides a good reason for those not wanting to include such behaviour in diagnostic psychiatry texts.
Dr. Mark Griffiths, Professor of Behavioural Addiction, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Bocij, P., Griffiths, M.D., McFarlane, L. (2002). Cyberstalking: A new challenge for criminal law. Criminal Lawyer, 122, 3-5.
Cooper, A., Delmonico, D.L., & Burg, R. (2000). Cybersex users, abusers, and compulsives: New findings and implications. Sexual Addiction and Compulsivity, 6, 79-104.
Cooper, A., Delmonico, D.L., Griffin-Shelley, E., & Mathy, R.M. (2004). Online sexual activity: An examination of potentially problematic behaviors. Sexual Addiction and Compulsivity, 11, 129-143.
Cooper, A., Galbreath, N., Becker, M.A. (2004). Sex on the Internet: Furthering our understanding of men with online sexual problems. Psychology of Addictive Behaviors, 18, 223-230.
Cooper, A., Griffin-Shelley, E., Delmonico, D.L., Mathy, R.M. (2001). Online sexual problems: Assessment and predictive variables. Sexual Addiction and Compulsivity, 8, 267-285.
Dhuffar, M. & Griffiths, M.D. (2015). A systematic review of online sex addiction and clinical treatments using CONSORT evaluation. Current Addiction Reports, 2, 163-174.
Griffiths, M.D. (2000). Excessive internet use: Implications for sexual behavior. CyberPsychology and Behavior, 3, 537-552.
Griffiths, M.D. (2001). Sex on the internet: Observations and implications for sex addiction. Journal of Sex Research, 38, 333-342.
Griffiths, M.D. (2004). Sex addiction on the Internet. Janus Head: Journal of Interdisciplinary Studies in Literature, Continental Philosophy, Phenomenological Psychology and the Arts, 7(2), 188-217.
Griffiths, M.D. (2005). A ‘components’ model of addiction within a biopsychosocial framework. Journal of Substance Use, 10, 191-197.
Griffiths, M.D. (2012). Internet sex addiction: A review of empirical research. Addiction Research and Theory, 20, 111-124.
Griffiths, M.D. (2016). Compulsive sexual behaviour as a behavioural addiction: The impact of the Internet and other issues. Addiction, 111, 2107-2109.
Griffiths, M.D. & Dhuffar, M. (2014). Treatment of sexual addiction within the British National Health Service. International Journal of Mental Health and Addiction, 12, 561-571.
Kraus, S., Voon, V., & Potenza, M. (2016). Should compulsive sexual behavior be considered an addiction? Addiction 111, 2097-2106.
Orzack M.H., & Ross C.J. (2000). Should virtual sex be treated like other sex addictions? Sexual Addiction and Compulsivity, 7, 113-125.
Sussman, S., Lisha, N. & Griffiths, M.D. (2011). Prevalence of the addictions: A problem of the majority or the minority? Evaluation and the Health Professions, 34, 3-56.
Van Gordon, W., Shonin, E., & Griffiths, M.D. (2016). Meditation Awareness Training for the treatment of sex addiction: A case study. Journal of Behavioral Addictions, 5, 363–372.
Sense and sense-ability: A brief look at ‘virtual reality addiction’
Ever since I started researching into technological addictions, I have always speculated that ‘virtual reality addiction’ was something that psychologists would need to keep an eye on. In 1995, I coined the term ‘technological addictions’ in a paper of the same name in the journal Clinical Psychology Forum. In the conclusions of that paper I asserted:
“There is little doubt that activities involving person-machine interactivity are here to stay and that with the introduction of such things [as] virtual reality consoles, the number of potential technological addictions (and addicts) will increase. Although there is little empirical evidence for technological addictions as clinical entities at present, extrapolations from research into fruit machine addiction and the exploratory research into video game addiction suggest that they do (and will) exist”.
Although I wrote the paper over 20 years ago, there is little scientific evidence (as yet) that individuals have become addicted to virtual reality (VR). However, that is probably more to do with the fact that – until very recently – there had been little in the way of affordable VR headsets. (I ought to just add that when I use the term ‘VR addiction’ what I am really talking about is addiction to the applications that can be utilized via VR hardware rather than the VR hardware itself).
VR’s potential in mass commercial markets appears to be finally taking off because of mass-produced affordable hardware such as Oculus Rift, HTC Vive, PlayStation VR and the (ultra-cheap) Google Cardboard (in which a smartphone can be inserted into cardboard VR headset frame). Last year, a report by the marketing and consulting company Tractica claimed that spending on virtual reality hardware could be as much as $21.8 billion (US) by 2020. A more recent report by online and digital market research company Juniper estimated that global sales of VR headsets would rise from 3 million in 2016 to 30 million by 2020. Three markets are likely drive sales, and they all happen to be areas that I research into from an addiction perspective – video gaming, gambling, and sex. I’ve noted in many of my academic papers over the years (particularly my early papers on online gambling addiction and online sex addiction) that when new technological advances occur, the sex and gambling industries always appear to be the first to invest and produce commercial products and services using such technologies, and VR is no different. As an online article in Wareable by Dan Sung on VR sex noted:
“What [VR] headsets offer is immersion; 180-degree (or more), stereoscopic action with you as the star of the show and the adult actors and actresses looking deep and lustfully into your eyes as they tend to your genitalia. It’s small wonder that users have been donning their headsets and earphones in numbers and praying to their god that nobody walks in. Yet gambling and porn are synonymous with addiction, and increasingly, questions are being asked about whether the VR revolution could finally ensnare us humans into virtual worlds”.
I was interviewed by Sung for the same article and I made a number of different observations about VR sex. I commented that in terms of people feeling reinforced, aroused, rewarded, sex is the ultimate in things that are potentially addictive. Sex is one of those activities that is highly reinforcing, it’s highly rewarding and how people feel is probably better than the highs and buzzes from other behaviours. Theoretically, I can see that VR sex addiction would be possible but I don’t think it’s going to be on the same scale as other more traditional addictions. The thing about VR (and VR sex) – and similarly to the internet – is that it’s non-face-to-face, it’s non-threatening, it’s destigmatising, and it’s non-alienating. VR sex could be like that whether it’s with fictitious partners, someone that you’re actually into, or someone that you’ve never met before. Where VR sex is concerned, if you can create a celebrity in a totally fictitious way, that will happen. There may be celebrities out there that will actually endorse this and can make money and commercialise themselves to do that. It can work both ways. Some people might find it creepy while others might see something they can make money from.
In one of my previous blogs I looked at the area of ‘teledildonics’, a VR technology that has been around for over two decades (in fact I was first interviewed on this topic on a 1993 Channel 4 television programme called Checkout ’93). Dan Sung also interviewed Kyle Machulis who runs the Metafetish teledildonics website for his article. He said that in relation to VR sex there is a problem with haptics (i.e., the science of applying tactile sensation and control to interaction with computer applications):
“We’re good on video and audio but haptics is a really, really hard problem…A lot of toys out there right now are horrible and it’s very hard to come up with something quality. So, instead, what the porn industry is aiming for right now is immersion. It may not feel better but they’re so much closer to the action that it may be better, and I think we’re on the cusp of that right now.” First, we need consumer hardware. We need things to be released and available to customers to see if it’s really going to take off or not. But when this happens – late this year, the beginning of next – as soon as the headsets are available, the media is ready and waiting…Of course, there’s straight women, gay men and gay women to develop for too but, for a lot of people, the perfect porn experience is doing something that’s not even physically possible – either through the laws of physics or the laws of land, and that’s something that only VR can solve…Even so, what we saw in teledildonics in gaming is that people used them to begin with but there’s always a lot of fall off with new technologies like this. So, there’s going to be a hardcore set of people who stay with VR porn but it’s hard to say how popular it will be beyond that. We’re all still guessing at the moment. This time next year it will be a completely different story”.
Another area that we will need to monitor is how the gambling industry will harness VR technology. The most obvious application of VR in the gambling world is in the online gambling sector. I can imagine some online gamblers wanting their gambling experiences to be more immersive and for their online gambling sessions to be more akin to gambling offline surrounded by the sights and sounds of an offline gambling venue. There is no technical reason that I know of why people that gamble via their computers, laptops, smartphones or tablets could not wear VR headsets and be playing poker opposite a virtual opponent while still sat on the sofa at home. As Paul Swaddle (CEO of Pocket App) noted in a recent issue of Gambling Insider:
We already know that participation in online gambling is snowballing, so if the entertainment industry can use VR to simulate the experience of being inside a video game, or social media sites can give you the opportunity to not just see your friends’ pictures, but to walk through them, why shouldn’t online casinos be able to do the same? VR may actually be the hook that mobile and online casinos need to draw in more millennials, with the average age of players in mobile casinos currently being 40 [years old], and the average age of mobile gamblers in general being 35 [years old]. Millennials simply aren’t engaging with mobile and online casinos to the same extent as older generations, and I suspect that this is down to younger players being much more used to immersive and sociable gaming, as a result of the cutting-edge developments that are being constantly rolled out in the video gaming industry”.
I agree with Swaddle’s observations as the gambling industry are constantly thinking about the ways to bring in newer players. Today’s modern screenagers love technology and do not appear to have any hang-ups about using wearable technology including Fitbit and the Apple Watch. As Swaddle goes on to say:
“By using VR technology to transport players and their friends to exciting locations for their online gambling experience, such as a famous casino in Las Vegas, or a smoky basement room in 1920s New York, or even to the poker table in the James Bond film Casino Royale, mobile and online casinos may stand a better chance of drawing in younger audiences if they use VR to gamify the casino experience”.
Again, this makes a lot of sense to me and I wouldn’t bet against this happening. Swaddle thinks that such VR gambling experiences will become commonplace in the years to come and that the gambling industry needs to get on the VR bandwagon now.
Perhaps of most psychological concern is the use of VR in video gaming. There is a small minority of players out there who are already experiencing genuine addictions to online gaming. VR takes immersive gaming to the next level, and for those that use games as a method of coping and escape from the problems they have in the real world it’s not hard to see how a minority of individuals will prefer to spend a significant amount of their waking time in VR environments rather than their real life.
Dr Mark Griffiths, Professor of Behavioural Addiction, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Ashcroft, S. (2015). VR revenue to hit $21.8 billion by 2020. Wareable, July 29. Located at: http://www.wareable.com/vr/vr-revenues-could-reach-dollar-218-billion-by-2020-1451
Griffiths, M.D. (1995). Technological addictions. Clinical Psychology Forum, 76, 14-19.
Griffiths, M.D. (1996). Gambling on the internet: A brief note. Journal of Gambling Studies, 12, 471-474.
Griffiths, M.D. (2001). Sex on the internet: Observations and implications for sex addiction. Journal of Sex Research, 38, 333-342.
Griffiths, M.D. (2003). Internet gambling: Issues, concerns and recommendations. CyberPsychology and Behavior, 6, 557-568.
Griffiths, M.D. (2012). Internet sex addiction: A review of empirical research. Addiction Research and Theory, 20, 111-124.
Griffiths, M.D., Király, O., M. Pontes, H.M. & Demetrovics, Z. (2015). An overview of problematic gaming. In Starcevic, V. & Aboujaoude, E. (Eds.), Mental Health in the Digital Age: Grave Dangers, Great Promise (pp.27-55). Oxford: Oxford University Press.
Juniper Research (2016). White paper: The rise of virtual reality. Available from: http://www.juniperresearch.com/document-library/white-papers/the-rise-of-virtual-reality
Király, O., Nagygyörgy, K., Koronczai, B., Griffiths, M.D. & Demetrovics, Z. (2015). Assessment of problematic internet use and online video gaming. An overview of problematic gaming. In Starcevic, V. & Aboujaoude, E. (Eds.), Mental Health in the Digital Age: Grave Dangers, Great Promise (pp.46-68). Oxford: Oxford University Press.
Stables, J. (2016). Gambling, gaming and porn: Research says VR is set to blast off. Wareable, September 15. Located at: http://www.wareable.com/vr/gaming-gambling-and-porn-research-says-vr-is-set-to-blast-off-1682
Swaddle, P. (2016). Is virtual reality the future of mobile and online gambling? Gambling Insider, 23, June 3, p.9
Sung, D. (2015). VR and vice: Are we heading for mass addiction to virtual reality fantasies? Wareable, October 15. Located at: http://www.wareable.com/vr/vr-and-vice-9232
Tractica (2015). Virtual reality for consumer markets. Available at: https://www.tractica.com/research/virtual-reality-for-consumer-markets/
Specific limb: A brief look at ‘restless legs syndrome’
Those that know me well often comment that I have a general inability to sit still and that I am a ‘fidget’. (This is not necessarily a bad thing and in fact there are some positives to fidgeting that I outlined in a previous blog on bad behaviours that are sometimes good for you). There is certainly some truth to the observation that I fidget but sometimes the fidgeting is out of my control. Every few weeks my right lower leg appears to take on a life of its own and I will get strange (uncomfortable) sensations (such as tingling, itching, and aching, and occasionally cramp-like feelings) that force me to move my right leg and foot around. It only happens when I am in a resting and relaxing state and usually lasts about 30 minutes (but can occasionally last much longer). On occasions it disrupts my work and sleep but I find that just getting up and moving around is sometimes enough to alleviate the uncomfortable feelings.
A few years ago I Googled my ‘symptoms’ and was surprised to find that I am not the only person who appears to experience such effects and that there is a whole medical literature on what has been termed ‘restless legs syndrome’ although in my case it would be in a singular rather than plural form). I’ve had the condition for about 15 years now and it may be related to some of the medication I take for an unrelated chronic degenerative health condition that I have. According to the Wikipedia entry on restless legs syndrome (RLS):
“The first known medical description of RLS was by Sir Thomas Willis in 1672. Willis emphasized the sleep disruption and limb movements experienced by people with RLS…The term ‘fidgets in the legs’ has also been used as early as the early nineteenth century. Subsequently, other descriptions of RLS were published, including those by Francois Boissier de Sauvages (1763), Magnus Huss (1849), Theodur Wittmaack (1861), George Miller Beard (1880), Georges Gilles de la Tourette (1898), Hermann Oppenheim (1923) and Frederick Gerard Allison (1943). However, it was not until almost three centuries after Willis, in 1945, that Karl-Axel Ekbom (1907–1977) provided a detailed and comprehensive report of this condition in his doctoral thesis, Restless legs: clinical study of hitherto overlooked disease. Ekbom coined the term “restless legs” and continued work on this disorder throughout his career. He described the essential diagnostic symptoms, differential diagnosis from other conditions, prevalence, relation to anemia, and common occurrence during pregnancy. Ekbom’s work was largely ignored until it was rediscovered by Arthur S. Walters and Wayne A. Hening in the 1980s. Subsequent landmark publications include 1995 and 2003 papers, which revised and updated the diagnostic criteria”.
As well as being referred to as RLS, it is sometimes referred to as Willis-Ekbom Disease or Willis-Ekbom Syndrome. Since being ‘rediscovered’ in the 1980s, there have been a lot of scientific papers published on the phenomenon although many of these are medical case studies (I don’t think my own experiences are extreme enough or strong enough to appear in any medical textbook. The Wikipedia entry on RLS provides a good summary of what is known medically and empirically:
“Restless legs syndrome (RLS) is a disorder that causes a strong urge to move one’s legs. There is often an unpleasant feeling in the legs that improves somewhat with moving them. Occasionally the arms may also be affected. The feelings generally happen when at rest and therefore can make it hard to sleep. Due to the disturbance in sleep, people with RLS may have daytime sleepiness, low energy, irritability, and a depressed mood. Additionally, many have limb twitching during sleep. Risk factors for RLS include low iron levels, kidney failure, Parkinson’s disease, diabetes, rheumatoid arthritis, and pregnancy. A number of medications may also trigger the disorder including antidepressants, antipsychotics, antihistamines, and calcium channel blockers. There are two main types. One is early onset RLS which starts before age 45 [years], runs in families and worsens over time. The other is late onset RLS which begins after age 45 [years], starts suddenly, and does not worsen. Diagnosis is generally based on a person’s symptoms after ruling out other potential causes… Females are more commonly affected than males and it becomes more common with age…Some doctors express the view that the incidence of restless leg syndrome is exaggerated by manufacturers of drugs used to treat it. Others believe it is an under-recognized and undertreated disorder…An association has been observed between attention deficit hyperactivity disorder (ADHD) and RLS or periodic limb movement disorder. Both conditions appear to have links to dysfunctions related to the neurotransmitter dopamine, and common medications for both conditions among other systems, affect dopamine levels in the brain”.
According to a review by Dr. Richard Allen and Dr. Christopher Earley in the Journal of Clinical Neurophysiology, RLS affects 2.5-15% of the US population. In another review on sleep disorder in the journal American Family Physician, Dr. Kannan Ramar and Dr. Eric Olson reported that RLS is typically characterized by four essential features: These are:
“(1) the intense urge to move the legs, usually accompanied or caused by uncomfortable sensations (e.g., “creepy crawly,” aching) in the legs; (2) symptoms that begin or worsen during periods of rest or inactivity; (3) symptoms that are partially or totally relieved by movements such as walking or stretching; and (4) symptoms that are worse or only occur in the evening or at night”.
Various online articles and papers report a variety of potential treatments based on the notion that RLS might be caused by a dopamine imbalance in the body. Some medics advise a regular sleep routine (such as that advised for those with insomnia), and cutting out the drinking of alcohol and the smoking of cigarettes. Pharmacological treatments include the use of drugs that are also used in the treatment of Parkinson’s disease such as L-DOPA and pramipexole, and the use of magnesium sulphate therapy (as reported in a 2006 paper in the Journal of Clinical Sleep Medicine – magnesium is known to be a natural muscle relaxant). In a 2011 issue of the journal Sleep Medicine, In an online article about RLS, Dr Michael Platt, author of the 2014 book Adrenalin Dominance, claims that RLS sufferers can be treated using a progesterone cream:
“Excess adrenalin during the night can cause restless leg syndrome. People often have associated symptoms also resulting from elevated adrenalin, such as teeth grinding, the need to urinate, and tossing and turning, and they often awaken in the morning with low back pain. Characteristically, RLS patients have an excess of adrenaline, may toss and turn all night, be quick to anger, might be workaholics, will usually have fibromyalgia (aches and pains – low back, side of the hips, and grind their teeth), they might drink too much, and will be hypoglycemic (sleepy between 3-4 p.m. or when in a car), and so on. There is an associated over-production of insulin and an under-production of progesterone…[By using a progesterone cream] I have had 100% success with eliminating RLS by getting hormones into balance, often within the first week. Patients feel more relaxed, they can sleep at night, rage disappears, and they can focus more easily”.
Dr. Luis Marin and his colleagues reported a different treatment for RLS altogether. They reported the case of a 41-year-old male RLS sufferer who after being on medication for RLS discovered his own solution – having sex. Following sex, the man reported that all RLS symptoms would disappear. Marin and colleagues speculated that the release of dopamine following orgasm might alleviate RLS symptoms. This appears to be a reasonable speculation given the findings of research published in the Journal of Neuroscience by Dr. Gert Holstege and his colleagues who examined brain activation at the point of ejaculation. In their paper they reported the similarity between ejaculation and using heroin in terms of brain activation:
“We used positron emission tomography to measure increases in regional cerebral blood flow during ejaculation compared with sexual stimulation in heterosexual male volunteers. Manual penile stimulation was performed by the volunteer’s female partner. Primary activation was found in the mesodiencephalic transition zone, including the ventral tegmental area, which is involved in a wide variety of rewarding behaviors. Parallels are drawn between ejaculation and heroin rush”.
It could well be that the increase in dopamine following ejaculation acts in a similar way to the medications that are given to RLS sufferers. Of all the treatments for RLS that I have read about, I think I know which one I would prefer!
Dr. Mark Griffiths, Professor of Behavioural Addiction, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Allen, R.P., & Earley, C.J. (2001). Restless legs syndrome: A review of clinical and pathophysiologic features. Journal of Clinical Neurophysiology, 18(2), 128-147.
Bartell S1, Zallek S. Intravenous magnesium sulfate may relieve restless legs syndrome in pregnancy. Journal of Clinical Sleep Medicine, 15, 187-188.
Chaudhuri, K.R., Appiah-Kubi, L.S., & Trenkwalder, C. (2001). Restless legs syndrome. Journal of Neurology, Neurosurgery & Psychiatry, 71(2), 143-146.
Ekbom, K., & Ulfberg, J. (2009). Restless legs syndrome. Journal of Internal Medicine, 266(5), 419-431.
Holstege, G., Georgiadis, J. R., Paans, A. M., Meiners, L. C., van der Graaf, F. H., & Reinders, A. S. (2003). Brain activation during human male ejaculation. Journal of Neuroscience, 23(27), 9185-9193
Leschziner, G., & Gringras, P. (2012). Restless legs syndrome. British Medical Journal, 344, e3056.
Marin, L.F., Felicio, A.C., & Prado, G.F. (2011). Sexual intercourse and masturbation: Potential relief factors for restless legs syndrome? Sleep Medicine, 12(4), 422.
Ondo, W. G. (2009). Restless legs syndrome. Neurologic Clinics, 27(3), 779-799.
Ramar, K; Olson, EJ (Aug 15, 2013). Management of common sleep disorders. American Family Physician, 88, 231–238.
Satija, P., & Ondo, W. G. (2008). Restless legs syndrome. CNS Drugs, 22(6), 497-518.
Higher and higher: Can psychoactive substance use enhance creativity?
In a previous blog I examined whether celebrities are more prone to addictions. In that article I argued that many high profile celebrities have the financial means to afford a drug habit like cocaine or heroin. For many in the entertainment business such as being the lead singer in a famous rock band, taking drugs may also be viewed as one of the defining behaviours of the stereotypical ‘rock ‘n’ roll’ lifestyle. In short, it’s almost expected. There is also another way of looking at the relationship between celebrities and drugs and this is in relation to creativity, particularly as to whether the use of drugs can inspire creative writing or music. For instance, did drugs like cannabis and LSD help The Beatles create some of the best music ever such as Revolver? Did the Beach Boys’ Brian Wilson’s use of drugs play a major role in why the album Pet Sounds is often voted the best album of all time? Did the use of opium by Edgar Allen Poe create great fiction? Did William S. Burroughs’ use of heroin enhance his novel writing?
To investigate the question of whether drug use enhances creativity, I and my research colleagues Fruzsina Iszáj and Zsolt Demetrovics have just published a review paper in the International Journal of Mental Health and Addiction examining this issue. We carried out a systematic review of the psychological literature and reviewed any study that provided empirical data on the relationship between psychoactive substance use and creativity/artistic creative process that had been published in English in peer-reviewed journals or scientific books. Following a rigorous filtering process, we were surprised to find only 19 studies that had empirically examined the relationship between drug use and creativity (14 empirical studies and five case studies).
Six of the 19 studies (four empirical papers and two case reports) were published during the 1960s and 1970s. However, following the peak of psychedelia, only three papers (all of them empirical) were published in the following 20 years. Since 2003, a further 10 studies were published (seven empirical papers and three case studies). The majority of the studies (58%) were published in the USA. This dominance is especially true for the early studies in which six of the seven empirical papers and both case studies that were published before mid-1990s were written by US researchers. However, over the past 14 years, this has changed. The seven empirical papers published post-2000 were shared between six different countries (USA, UK, Italy, Wales, Hungary, Austria), and the three case studies came from three countries (USA, UK, Germany).
Seven empirical papers and two case studies dealt with the relationship between various psychoactive substances and artistic creation/creativity. Among the studies that examined a specific substance, six (three empirical papers and three case studies) focused on the effects of either LSD or psilocybin. One empirical study focused on cannabis, and one concerned ayahuasca.
With the exception of one study where the sample focused on adolescents, all the studies comprised adults. More non-clinical samples (15 studies, including case studies) were found than clinical ones (four studies). Three different methodological approaches were identified. Among the empirical studies, seven used questionnaires comprising psychological assessment measures such as the Torrance Test of Creative Thinking (TTCT).
According to the types of psychoactive substance effect on creativity, we identified three groups. These were studies that examined the effect of psychedelic substances (n=5), the effect of cannabis (n=1), and those that did not make a distinction between substances used because of the diverse substances used by participants in the samples (n=7). In one study, the substances studied were not explicitly identified.
The most notable observation of our review was that the findings of these studies show only limited convergence. The main reason for this is likely to be found in the extreme heterogeneity concerning the objectives, methodology, samples, applied measures, and psychoactive substances examined among the small number of studies. Consequently, it is hard to draw a clear conclusion about the effect of psychoactive substance use on creativity based on the reviewed material.
Despite the limited agreement, most of the studies confirmed some sort of association between creativity and psychoactive substance use, but the nature of this relationship was not clearly established. The frequently discussed view that the use of psychoactive substances leads to enhanced creativity was by no means confirmed. What the review of relevant studies suggests is that: (i) substance use is more characteristic in those with higher creativity than in other populations, and (ii) it is probable that this association is based on the inter-relationship of these two phenomena. At the same time, it is probable that there is no evidence of a direct contribution of psychoactive substances to enhanced creativity of artists.
It is more likely that substances act indirectly by enhancing experiences and sensitivity, and loosening conscious processes that might have an influence on the creative process. This means the artist will not be more creative but the quality of the artistic product will be altered due to substance use. On the other hand, it appears that psychoactive substances may have another role concerning artists, namely that they stabilize and/or compensate a more unstable functioning.
Beyond the artistic product, we also noted that (iii) specific functions associated with creativity appear to be modified and enhanced in the case of ordinary individuals due to psychoactive substance use. However, it needs to be emphasized that these studies examined specific functions while creativity is a complex process. In light of these studies, it is clear that psychoactive substances might contribute to a change of aesthetic experience, or enhanced creative problem solving. One study (a case study of the cartoonist Robert Crumb) showed that LSD changed his cartoon illustrating style. Similarly, a case study of Brian Wilson argued that the modification of musical style was connected to substance use. However, these changes in themselves will not result in creative production (although they may contribute to the change of production style or to the modification of certain aspects of pieces of arts). What was also shown is that (iv) in certain cases, substances may strengthen already existing personality traits.
In connection with the findings reviewed, one should not overlook that studies focused on two basically different areas of creative processes. Some studies examined the actual effects of a psychoactive substance or substances in a controlled setting, while others examined the association between creativity and chronic substance users. These two facets differ fundamentally. While the former might explain the acute changes in specific functions, the latter may highlight the role of chronic substance use and artistic production.
It should also be noted that the studies we reviewed differed not only regarding their objectives and methodology, but also showed great heterogeneity in quality. Basic methodological problems were identified in many of these studies (small sample sizes, unrepresentative samples, reliance on self-report and/or non-standardized assessment methods, speculative research questions, etc.). Furthermore, the total number of empirical studies was very few. At the same time, the topic is highly relevant both in order to understand the high level of substance use in artists and in order to clarify the validity of the association present in public opinion. However, it is important that future studies put specific emphasis on adequate methodology and clear research questions.
Dr. Mark Griffiths, Professor of Behavioural Addiction, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Belli, S. (2009). A psychobiographical analysis of Brian Douglas Wilson: Creativity, drugs, and models of schizophrenic and affective disorders. Personality and Individual Differences, 46, 809-819.
Dobkin de Rios, M. & Janiger, O. (2003). LSD, spirituality, and the creative process. Rochester, VT: Park Street Press.
Edwards, J. (1993). Creative abilities of adolescent substance abusers. Journal of Group Psychotherapy, Psychodrama & Sociometry, 46, 52-60.
Fink, A., Slamar-Halbedl, M., Unterrainer, H.F. & Weiss, E.M. (2012). Creativity: Genius, madness, or a combination of both? Psychology of Aesthetics, Creativity, and the Arts, 6(1), 11–18.
Forgeard, M.J.C. & Elstein, J.G. (2014). Advancing the clinical science of creativity. Frontiers in Psychology, 5, 613.
Frecska, E., Móré Cs. E., Vargha, A. & Luna, L.E. (2012). Enhancement of creative expression and entoptic phenomena as after-effects of repeated ayahuasca ceremonies. Journal of Psychoactive Drugs, 44, 191-199
Holm-Hadulla, R.M. & Bertolino, A. (2014). Creativity, alcohol and drug abuse: The pop icon Jim Morrison. Psychopathology, 47,167-73
Iszáj, F. & Demetrovics, Z. (2011). Balancing between sensitization and repression: The role of opium in the life and art of Edgar Allan Poe and Samuel Taylor Coleridge. Substance Use and Misuse, 46, 1613-1618
Iszaj, F., Griffiths, M.D. & Demetrovics, Z. (2016). Creativity and psychoactive substance use: A systematic review. International Journal of Mental Health and Addiction. doi: 10.1007/s11469-016-9709-8
Jones, M.T. (2007). The creativity of crumb: Research on the effects of psychedelic drugs on the comic art of Robert Crumb. Journal of Psychoactive Drugs, 39, 283-291.
Jones, K.A., Blagrove, M. & Parrott, A.C. (2009). Cannabis and ecstasy/ MDMA: Empirical measures of creativity in recreational users. Journal of Psychoactive Drugs. 41(4), 323-329
Kerr, B. & Shaffer, J. & Chambers, C., & Hallowell, K. (1991). Substance use of creatively talented adults. Journal of Creative Behavior, 25(2), 145-153.
Knafo, D. (2008). The senses grow skilled in their craving: Thoughts on creativity and addiction. Psychoanalytic Review, 95, 571-595.
Lowe, G. (1995). Judgements of substance use and creativity in ’ordinary’ people’s everyday lifestyles. Psychological Reports. 76, 1147-1154.
Oleynick, V.C., Thrash, T. M., LeFew, M. C., Moldovan, E. G. & Kieffaber, P. D. (2014). The scientific study of inspiration in the creative process: challenges and opportunities. Frontiers in Human Neuroscience, 8, 436.
Plucker, J.A., McNeely, A. & Morgan, C. (2009). Controlled substance-related beliefs and use: Relationships to undergraduates’ creative personality traits. Journal of Creative Behavior, 43(2), 94-101
Preti, A. & Vellante, M. (2007). Creativity and psychopathology. Higher rates of psychosis proneness and nonright-handedness among creative artists compared to same age and gender peers. Journal of Nervous and Mental Disease, 195(10), 837-845.
Schafer, G. & Feilding, A. & Morgan, C. J. A. & Agathangelou, M. & Freeman, T. P. & Curran, H.V. (2012). Investigating the interaction between schizotypy, divergent thinking and cannabis use. Consciousness and Cognition, 21, 292–298
Thrash, T.M., Maruskin, L.A., Cassidy, S. E., Fryer, J.W. & Ryan, R.M. (2010). Mediating between the muse and the masses: inspiration and the actualization of creative ideas. Journal of Personality and Social Psychology, 98, 469–487.
One giant step for man: Another look at macrophilia
Earlier this week, an article by Felicity Monk was published on the Broadly website about macrophilia (individuals derive sexual arousal from a fascination with giants and/or a sexual fantasy involving giants) and also known as giant (or giantess) fetishism. Broadly is an offshoot of Vice.com and is a website is a website “devoted to representing the multiplicity of women’s experiences”. I have been interviewed by both Broadly and Vice over the last few years on a number of topics including gambling, dacryphilia, and Alice in Wonderland Syndrome. I was interviewed for the Broadly article mainly because I’m one of the few academics ever to have written an article on the topic. I was quoted as saying in the Broadly article that “no-one has ever published even so much as an interview with a macrophile in an academic journal”.
In the Broadly article, Monk managed to interview a couple of macrophiles including Katelyn, a bisexual female in her thirties (five foot two inches tall) who has a number of co-occurring fetishes including macrophilia (in which she is sexually aroused by the thought of being a giant). She also has her own giantess website (which can be accessed here, but please be warned that the site features sexually explicit content) which she set up so that macrophiles could come and “worship” her. For Katelin, her macrophilic tendencies started from watching Tom and Jerry cartoons and the disparate size of the characters. As Katelyn said:
“The first time I had a good tingly feeling was when I was watching Tom have so much fun trying to catch Jerry. I always liked how Jerry got away so that the game would continue. I so badly wanted to be that cat. Little did I know it was the start of my sexuality. [By the time I got to high school I] was fantasising about literally crushing [my] high school crushes, swallowing [my] boyfriends and girlfriends alive, and putting [my] entire foot through the school. Most of the time I felt out of place and very alone sexually. [My preferred size of being a giant] changes depending on what mood [I’m] in. Some days I’m in the mood to play with the entire earth/galaxy, and other times I’m in the mood to attack a lone city as a 100ft woman. I rarely go below 100 feet. Most commonly, however, I’m fantasizing about being mega – 3000-plus feet tall”.
Katelyn has now monetized her fetish by turning her website into a commercial venture. As the article in Broadly notes:
“[On Katelyn’s website you] will find videos for sale – many of which feature miniature, plastic people being swallowed or crushed under huge feet. There are also stories, comics, photographs, collages, a blog, and a link to Katelyn’s Amazon wish list, so her worshippers can purchase her gifts: underwear, Starbucks gift cards, vitamins so she can ‘grow’ bigger, and non-stick saucepans. Visiting the site is free, but each month around 700 of her fans make a purchase”.
My own research into macrophilia suggests that the overwhelming majority of macrophiles appear to be heterosexual males that are sexually attracted to female giantesses. However, I’ve also noted that even non-sexual scenarios involving giants can result in sexual stimulation. Each fantasy situation is different for every macrophile as the behaviour is fantasy-based. Even the preferred heights of the fantasy giants differ between individuals. For instance, some macrophiles have a preference for people only a few feet taller than themselves, whereas others involve giants who are hundreds of feet high.
In the Broadly article, Katelyn admitted she had other sexual fetishes including an “extreme mouth fetish” of similar intensity to her giantess fetish as well as furry and hentai fetishes (anime and manga pornography). This concurs with what I noted in my previous blog on macrophilia where I said that it had also been associated with other sexual paraphilias. I claimed the most noteworthy were:
- Breast fetishism: This is a sexual fetish in which an individual derives sexual arousal from being pressed against, or placed in between, the breasts of a giant woman.
- Dominance/submission: This is a sexual fetish in which an individual derives sexual pleasure being at the mercy of a giant, or from being in control of a tiny person.
- Sadism/masochism: This is a sexual paraphilia in which an individual derives sexual pleasure from being physically harmed or even killed (in this case by a giant).
- Vorarephilia: This is a sexual paraphilia in which individuals derive sexual arousal from the idea of being eaten, eating another person, or observing this process. Although there are cases of real life vorarephilia (that I wrote about in a previous blog), the behaviour is typically fantasy-based (e.g., fictional stories, fantasy art, fantasy videos, and bespoke video games).
- Zoophilia: This is a sexual paraphilia in which individuals derive sexual pleasure from sex with animals (in this case, the desire is to have sex with a giant animal that is given human characteristics (i.e., anthropomorphism). This also has some crossover with furries (those individuals who – amongst other behaviours – like to dress as animals when having sex)
- Crush fetishism: This is a sexual fetish in which an individual derives sexual arousal from being stepped or sat on by a giant person, and is also a variant of sexual masochism.
When Monk interviewed me, one of the most important questions she wanted an answer for was how people develop macrophilic tendencies. I told her that the roots of most fetishes lie in childhood and early adolescence where sexual arousal is, at first, accidentally associated with giants – maybe watching a TV programme where a giantess initiates feelings of sexual arousal. Over time the giant itself is enough to cause sexual arousal through classical conditioning. However, as there are no case studies in the literature, this is complete speculation on my part. However, she also interviewed one of Katelyn’s ‘worshippers’ (‘Mark’) who appeared to confirm my speculative thoughts.
“[I remember] seeing a re-run of Attack of the 50 Foot Woman when [I] was around 13 years old. The [point of view] of Allison Hayes walking across the desert was the first time I can recall being turned on. Seeing her tear the roof off of the building to get at her husband overwhelmed my young brain at the time. Shortly after that, another movie called Village of the Giants did the same thing. I can remember one of the giantesses in the movie said something like ‘Oh, why don’t I just step on him?’ which again turned my underage mind on like nothing prior. I would be uncontrollably drawn to [the giantess’] beauty and power despite the danger such an encounter would bring. As a superior being, she would have little regard for me other than supplying her own needs. Whether it be as food to nourish her superior body, or as a sexual play toy to be used and broken after, I would have no other choice other than submit myself to her. To have my life be hers to do with as she pleased would become the sole purpose for my existence. The exhilaration, danger, fear and sexual excitement would outweigh my very instinct for survival. I only wish it would become real”.
For her article, Monk also interviewed the Australian sex and relationship therapist Pamela Supple. Supple claimed that:
“Power, domination and vulnerability are at the heart of macrophilia. It’s allowing your mind to go wherever it wants to go, whilst engaging in play to gain the maximum sexual arousal. Some want to feel and experience terror – being crushed or controlled. Everyone is different in what they want to experience.”
Both I and Supple agree that macrophilia has enjoyed a massive surge in popularity in the past few years, with both of us citing the crucial role of the internet in helping to both create and facilitate the fetish “and, in some cases, introducing the fetish to those who have been looking for a name for what they feel”. This was confirmed by another one of Katelyn’s worshippers (‘Semeraz’). As he explained:
“[I didn’t know macrophilia’ was a thing” until [I] discovered Katelyn’s website. Before then, remember being in fifth grade and playing a game where the teacher assigned team names of ‘predator’ and ‘prey’ and becoming excited when a girl taunted him saying: ‘We’re going to eat you!’ But I never thought of it as a sexual fetish until running into Katelyn’s site”.
Since writing my article on macrophilia over four years ago, the presence of maxcrophilia online appears to have grown. Katelyn claims that her website was very niche when she set it up a number of years ago:
“It only had a handful of websites and contributors, a lot of lurkers – fetishes were much more taboo a decade ago – the content production was scarce and I was the only girl who had come out of the closet with the giantess fetish. Members thought there was no way a girl could have the giantess fetish. That made me feel alone, because I was the only giantess, and a lot of people doubted my sexuality. Nowadays, there’s so much giantess fetish content that you wouldn’t be able to see everything in a lifetime. There are millions of collages, stories, artists, producers, models, videos, and more.”
I’m not sure there are “millions of collages, stories, artists, producers, models, videos” out there on the internet but macrophilia is probably a lot less rare than I thought a few years ago.
Dr Mark Griffiths, Professor of Behavioural Addiction, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Biles, J. (2004). I, insect, or Bataille and the crush freaks. Janus Head: Journal of Interdisciplinary Studies in Literature, Continental Philosophy, Phenomenological Psychology and the Arts, 7(1), 115-131.
Bowen, J. (1999). Urge: A giant fetish. Salon, May 22. Located at: http://www.salon.com/1999/05/22/macrophilia/
Gates, K. (2000). Deviant Desires: Incredibly Strange Sex. New York: RE/Search Publications.
Love, B. (1992). Encyclopedia of Unusual Sex Practices. Fort Lee, NJ: Barricade Books.
Monk, F. (2016). The men who want to have sex with actual giants. Broadly, October 26. Located at: https://broadly.vice.com/en_us/article/macrophilia-fetish-the-men-who-want-to-have-sex-with-actual-giants
Pearson, G.A. (1991). Insect fetish objects. Cultural Entomology Digest, 4, (November).
Ramses, S. (undated). Introduction to macrophilia. Located at: http://www.pridesites.com/fetish/mac4black/intro2macro.htm
Slothrop, T. (2012). The Bible and Macrophilia: He Thong’s Goliath Art. Remnant of Giants, February 6. Located at: https://remnantofgiants.wordpress.com/2012/02/06/the-bible-and-macrophilia-he-thongs-goliath-art/
Dying for it: Bizarre autoerotic deaths (Part 2)
In my previous blog I examined some of the most bizarre autoerotic deaths reported in the medical forensic literature. Here are another five.
Case 1: Autoerotic death by aerosol propellant
Source: Medicine, Science and the Law. Personal details: 32-year old white US man. Single. Computer programmer.
- Bizarre death event: Found dead in bed with cassette recorder next to him. He was wearing headphones which playing “snorting” horse sounds. There was also a can of aerosol propellant. At the end of the bed was a large painting of a male strapped to the hind legs of a horse who was being anally penetrating by the horse. The horse was ridden by a leather-clad woman. He was also wearing some kind if homemade masturbatory device. His death was recorded as cardio-respiratory failure consistent with aerosol propellant abuse (death by misadventure). Self-administration of the chemical agent to modify the sensations of masturbation. He was covered in dry semen stains.
Case 2: Autoerotic death by clothing
Source: Medicine, Science and the Law. Personal details: 25-year old Japanese male. Single.
- Bizarre death event: Man found dead in his bed one morning. naked except for clothing wrapping his head and underpants which were pulled down. He was covered in dry semen stains. He had put a black skirt on his face and then pulled a second skirt upside down over his head and turned down the bottom of it. He then put a plastic bag over these two garments followed by a pair of tights. The legs of the tights were used to tie a knot around the bottom of the skirts. He then wrapped a third skirt around all of this. Death was due to suffocation.
Case 3: Autoerotic death by hanging (female)
Source: Handbook of Forensic Pathology. Personal details: 19-year old white female. Single. College student.
- Bizarre death event: Woman was found dead in her bedroom hanging from the hinge of her closet door dressed as an Oriental “harem girl”. A window sash cord was tied around her body in a complicated fashion and she was also wearing a blindfold and mouth gag (made from the belt of her dressing gown). Next to her lay an underground magazine (this was folded out and showed a bizarre dance involving a clock – the minute hand being a nude male who would make love with the other figure on the hour), a paperback Hitchcock book which explained her fantasy. The paperback contained the story about an Oriental harem master. In this story the harem master provides girls to his lord who stored them by hanging them around his walls on hooks
Case 4: Autoerotic death by vacuum cleaner
Source: American Journal of Forensic Medicine and Pathology. Personal details: 57-year old white US male. Single. History of heart disease and chronic pancreatitis
- Bizarre death event: Man was found naked slumped over his vacuum cleaner after a neighbour wondered why the vacuum cleaner had been on continuously for a long time. The man was found leaning against the dining table with his testicles, buttocks and thighs tightly bound with women’s tights. Near the table was a jar of urine, jars of lubricant and a wooden table leg covered in fecal excrement. The man was covered in burns from the vacuum cleaner. No defect was found in the vacuum cleaner. The man basically had a heart attack while engaged in autoerotic activity. The wooden table leg had been used in an attempt to stimulate orgasm via anal penetration. His wife had caught him masturbating with the vacuum cleaner before (they hadn’t had sex for five years). The death was classed as natural rather than accidental.
Case 5: Autoerotic death by hydraulic tractor shovel
Source: Journal of Forensic Sciences. Personal details: 62 year-old US white male. Married. Farmer.
- Bizarre death event: Found dead in a barn lying on his front pinned under the hydraulic shovel of his tractor. His body was covered with semen stains and there was evidence of masochistic sexual bondage. His clothes were folded neatly away nearby. He was found naked except for a pair of women’s red shoes (with 8 inch heels), knee high stockings and tape duct wrapped around his ankles. Ropes led from his feet to the tractor which when raised would lift his inverted body causing complete suspension. It is not known exactly what happened but it is likely that the engine stalled and he was crushed underneath the tractor shovel. He died of positional asphyxiation by chest compression. This was an atypical autoerotic fatality because he did not purposely use asphyxiation but it did cause his death.
Dr. Mark Griffiths, Professor of Behavioural Addiction, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK
Further reading
Aggrawal A. (2009). Forensic and Medico-legal Aspects of Sexual Crimes and Unusual Sexual Practices. Boca Raton: CRC Press.
Byard, R. W. (1994). Autoerotic death—characteristic features and diagnostic difficulties. Journal of Clinical Forensic Medicine, 1(2), 71-78
Cordner, S.M. (1983). An unusual case of sudden death associated with masturbation. Medicine, Science and the Law, 23(1), 54-56
Dietz, P. E., & O’Halloran, R.L. (1993). Autoerotic fatalities with power hydraulics. Journal of Forensic Science, 38(2), 359-364.
Ikeda, N., Harada, A., Umetsu, K., & Suzuki, T. (1988). A case of fatal suffocation during an unusual auto-erotic practice. Medicine, Science and the Law, 28(2), 131-134.
Imami, R. H., & Kemal, M. (1988). Vacuum cleaner use in autoerotic death. American Journal of Forensic Medicine and Pathology, 9(3), 246-248.
Love, B. (2001). Encyclopedia of Unusual Sex Practices. London: Greenwich Editions.
Sauvageau, A., & Racette, S. (2006). Autoerotic deaths in the literature from 1954 to 2004: A review. Journal of Forensic Sciences, 51(1), 140-146.









