YBOP response to Jim Pfaus's "Trust a Scientist: Sex Addiction Is a Myth" (January, 2016)

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How about trusting addiction neuroscientists and peer-reviewed papers? 

Before I address many of the claims within the Pfaus article, it must be noted that Jim Pfaus omitted the 23 neuroscience-based studies on porn users published in the last few years. So far, the results of every "brain study" (MRI, fMRI, EEG, neuropsychological, neuro-hormonal) offer support for the concept of porn addiction. In addition to reporting the same fundamental brain changes as seen in substance addicts, a few studies also reported greater porn use is associated with erectile dysfunction, delayed ejaculation, decreased libido, and reduced neural response to images of vanilla porn. The up-to-date list of current "brain studies" is here. Clicking on the name of the study leads to the original paper. A 2016 review of "compulsive sexual behaviors" (CSB) by neuroscientists at Yale and Cambridge universities contains a section on the "Neurobiological Basis of CSB". This section alone exposes the Pfaus article for what it is: a propaganda piece.

The 23 studies on porn users also align with over 150 internet addiction "brain studies" (PET, MRI, fMRI, EEG) published in the last few years. Without exception, these studies reported the same addiction-related brain changes as seen in substance addicts. Internet porn addiction is, in fact, a subtype of internet addiction, as this recent review of the neuroscience literature pointed out - "Neuroscience of Internet Pornography Addiction: A Review and Update (2015)"

Let's examine the claims and distortions in this piece by Jim Pfaus:

PFAUS: "They’re not included in the Diagnostic and Statistical Manual of Mental Disorders (DSM), and by definition, they don’t constitute what most researchers understand to be addiction."

RESPONSE: The claim about "most researchers" is unsupported. Some of the top addiction researchers in the world recognize Internet porn addiction. Valerie Voon of Cambridge University, Marc Potenza of Yale University, Simone Kuhn of the Max Planck Institute, and many others have published studies the results of which support the porn addiction model. See this list.

Moreover, it appears that DSM sexuality work group member Richard Krueger MD told a Canadian journalist that he had no doubt internet porn addiction is real, and that he expected that the DSM would eventually include internet porn addiction when adequate research became available.

As for addiction experts, the American Society of Addiction Medicine (ASAM) published its new definition of addiction and stated that all addiction is one condition and that "sexual behavior addictions" not only exist but involve the same fundamental mechanisms and brain changes as do drug addictions. ASAM's 3000 medical doctors are many of the addiction researchers that provide the hard data, such head of NIDA, Nora Volkow, MD. PhD, and Eric Nestler MD, PhD.

QUOTE FROM ASAM FAQS -

5. QUESTION: "This new definition of addiction refers to addiction involving gambling, food, and sexual behaviors. Does ASAM really believe that food and sex are addicting?

ANSWER: "Addiction to gambling has been well described in the scientific literature for several decades. In fact, the latest edition of the DSM (DSM-V) will list gambling disorder in the same section with substance use disorders. The new ASAM definition makes a departure from equating addiction with just substance dependence, by describing how addiction is also related to behaviors that are rewarding. This is the first time that ASAM has taken an official position that addiction is not solely “substance dependence.” This definition says that addiction is about functioning and brain circuitry and how the structure and function of the brains of persons with addiction differ from the structure and function of the brains of persons who do not have addiction. It talks about reward circuitry in the brain and related circuitry, but the emphasis is not on the external rewards that act on the reward system. Food and sexual behaviors and gambling behaviors can be associated with the pathological pursuit of rewards described in this new definition of addiction."

As for the highly controversial and politicized DSM, it must be remembered that this same organization classified homosexuality as a mental disorder. The DSM doesn't determine reality, nor is reality up for a vote. It's quite telling that the head of The National Institute of Mental Health (NIMH), Tom Insel stated that the newly published DSM-5 "lacked validity". Insel stated that "patients deserve better" and that the NIMH would no longer fund research based on the DSM diagnostic categories. Insel was very clear we he stated,

"it is critical to realize that we cannot succeed if we use DSM categories as the “gold standard.”


PFAUS: "Here’s why: addicts withdraw......The same goes for a guy obsessed with watching porn. He might prefer to endlessly watch porn, but when he’s unable to, no withdrawal indicative of addiction occurs. He’ll never be physically addicted."

RESPONSE: Pfaus spends considerable text suggesting that "withdrawal symptoms" equal "addiction". First, it is well established in the addiction field that neither the presence nor absence of withdrawal symptoms determines the existence of an addiction. That said, porn addicts consistently report withdrawal symptoms that mirror drug withdrawal. Please see multiple reports on these pages:

Pfaus may claim these are only anecdotes, yet no published paper has yet asked porn addicts about the withdrawal symptoms they experience when they abstain from porn use. 

In saying that "physical symptoms" must be present for an addiction to exist, Pfaus is confusing addiction with physical dependence. For example, millions of individuals take chronically high levels of pharmaceuticals such as opioids for chronic pain, or prednisone for autoimmune conditions. Their brains and tissues have become dependent on them, and immediate cessation of use could cause severe withdrawals symptoms. However they are not necessarily addicted. Addiction involves multiple well-indentified brain changes that lead to what we know as the "addiction phenotype". If the distinction is unclear, I recommend this simple explanation by NIDA -

Pfaus's "withdrawal = addiction" argument falls apart when we consider that nicotine is often listed as the most addictive substance, and yet causes relatively mild withdrawal symptoms. Finally, the DSM-5 has added pathological gambling into the newly created behavioral addiction category, ending the argument that only drugs can cause and addiction, and with it the claim that "dependence" equals addiction. See this DSM-5 publication.


PFAUS: "As such, the anti-fapper narrative is usually the only point discussed: Guys stop masturbating after they stop downloading porn, and after a few days, they say they’re able to get normal erections again."

RESPONSE: Pfaus falsely claims it takes a "few days" for men with porn-induced ED to regain normal erectile functioning. Instead, it generally takes months, and up to two years, in some cases, for young men to achieve normal erections again. Pfaus has often spun the nonsensical story that porn-induced ED is cause by a refractory period. I've never heard of a 9-month refractory period for a 23-year old. Readers might find interesting this peer-reviewed paper describing porn-induced anorgasmia/loss of libido in a 35-year-old healthy man. It took 8-months of no porn for him to regain normal sexual functioning.


PFAUS: "This coincides with the somewhat popular idea that watching porn leads to erectile dysfunction, a position that porn-addiction advocates such as Marnia Robinson and Gary Wilson state emphatically."

RESPONSE: First, my book Your Brain on Porn: Internet Pornography and the Emerging Science of Addiction, which came out last year, addresses porn related sexual dysfunctions such as difficulty orgasming and sustaining erections. It has been endorsed by various experts. And I recommend it to anyone who wants to understand what is going on on recovery forums, as well as the relevant science (more of which has come out since, and all of which aligns with what I wrote).

Second, it's not just Gary Wilson. On this page readers can see articles and video by about 80 experts (urology professors, urologists, psychiatrists, psychologists, sexologists, MDs) who have successfully treated porn-induced ED and porn-induced loss of sexual desire

Several studies support what these experts have observed:

1) Peer-reviewed paper by US Navy doctors - Is Internet Pornography Causing Sexual Dysfunctions? A Review with Clinical Reports (2016) - It’s an extensive review of the literature on porn-induced sexual problems. The review provides the latest data revealing a tremendous rise in youthful sexual problems. The paper also examines the neurological studies related to porn addiction and sexual conditioning. The doctors provide 3 clinical reports of men who developed porn-induced sexual dysfunctions.

2) The Dual Control Model - The Role Of Sexual Inhibition & Excitation In Sexual Arousal And Behavior (2007) - Newly rediscovered and very convincing. In an experiment employing video porn, 50% of the young men couldn't become aroused or achieve erections with porn (average age was 29). The shocked researchers discovered that the men's erectile dysfunction was,

"related to high levels of exposure to and experience with sexually explicit materials."

The men experiencing erectile dysfunction had spent a considerable amount of time in bars and bathhouses where porn was "omnipresent," and "continuously playing". The researchers stated:

"Conversations with the subjects reinforced our idea that in some of them a high exposure to erotica seemed to have resulted in a lower responsivity to "vanilla sex" erotica and an increased need for novelty and variation, in some cases combined with a need for very specific types of stimuli in order to get aroused."

3) Neural Correlates of Sexual Cue Reactivity in Individuals with and without Compulsive Sexual Behaviours (2014) - This fMRI study by Cambridge University found sensitization in porn addicts which mirrored sensitization in drug addicts. It also found that porn addicts fit the accepted addiction model of wanting "it" more, but not liking "it" more. The researchers also reported that 60% of subjects (average age: 25) had difficulty achieving erections/arousal with real partners as a result of using porn, yet could achieve erections with porn. From the study (CSB is compulsive sexual behaviours):

"CSB subjects reported that as a result of excessive use of sexually explicit materials.....[they] experienced diminished libido or erectile function specifically in physical relationships with women (although not in relationship to the sexually explicit material)"

"Compared to healthy volunteers, CSB subjects had greater subjective sexual desire or wanting to explicit cues and had greater liking scores to erotic cues, thus demonstrating a dissociation between wanting and liking. CSB subjects also had greater impairments of sexual arousal and erectile difficulties in intimate relationships but not with sexually explicit materials highlighting that the enhanced desire scores were specific to the explicit cues and not generalized heightened sexual desire."

4) Online sexual activities: An exploratory study of problematic and non-problematic usage patterns in a sample of men (2016) - This Belgian study from a leading research university found problematic Internet porn use was associated with reduced erectile function and reduced overall sexual satisfaction. Yet problematic porn users experienced greater cravings. The study appears to report escalation, as 49% of the men viewed porn that "was not previously interesting to them or that they considered disgusting." Excerpts:

"This study is the first to directly investigate the relationships between sexual dysfunctions and problematic involvement in OSAs. Results indicated that higher sexual desire, lower overall sexual satisfaction, and lower erectile function were associated with problematic OSAs (online sexual activities). These results can be linked to those of previous studies reporting a high level of arousability in association with sexual addiction symptoms (Bancroft & Vukadinovic, 2004; Laier et al., 2013; Muise et al., 2013)."

In addition, we finally have a study that asks porn users about possible escalation to new or disturbing porn genres. Guess what it found?

"Forty-nine percent mentioned at least sometimes searching for sexual content or being involved in OSAs that were not previously interesting to them or that they considered disgusting, and 61.7% reported that at least sometimes OSAs were associated with shame or guilty feelings."

Note - Contrary to claims this is the first study to directly investigate the relationships between sexual dysfunctions and internet porn use. Two other studies claiming to have investigated correlations between porn use and erectile functioning cobbled together data from earlier studies in an unsuccessful attempt to debunk porn-induced ED. Both were criticized in the peer-reviewed literature: paper 1 was not an authentic study, and has been thoroughly discredited; paper 2 actually found correlations that support porn-induced ED. Moreover, paper 2 was only a "brief communication" that did not report important data.

5) Adolescents and web porn: a new era of sexuality (2015) - This Italian study analyzed the effects of Internet porn on high school seniors, co-authored by urology professor Carlo Foresta, president of the Italian Society of Reproductive Pathophysiology. The most interesting finding is that 16% of those who consume porn more than once a week report abnormally low sexual desire compared with 0% in non-consumers (and 6% for those who consume less than once a week). From the study:

"21.9% define it as habitual, 10% report that it reduces sexual interest towards potential real-life partners, and the remaining, 9.1% report a kind of addiction. In addition, 19% of overall pornography consumers report an abnormal sexual response, while the percentage rose to 25.1% among regular consumers."

6) Patient Characteristics by Type of Hypersexuality Referral: A Quantitative Chart Review of 115 Consecutive Male Cases (2015) - Study on men (average age 41.5) with hypersexuality disorders, such as paraphilias and chronic masturbation or adultery. 27 were classified as "avoidant masturbators," meaning they masturbated (typically with porn use) one or more hours per day or more than 7 hours per week. 71% reported sexual functioning problems, with 33% reporting delayed ejaculation (a precursor to porn-induced ED). What sexual dysfunction do 38% of the remaining men have? The study doesn't say, and the authors have ignored requests for details. Two primary choices for male sexual dysfunction are ED and low libido. The men were not asked about their erectile functioning without porn. If all their sexual activity involved masturbating to porn, and not sex with a partner, they might never realize they had porn-induced ED.

7) Altered Appetitive Conditioning and Neural Connectivity in Subjects With Compulsive Sexual Behavior (2016) - "Compulsive Sexual Behaviors" (CSB) means the men were porn addicts, because CSB subjects averaged nearly 20 hours of porn use per week. The controls averaged 29 minutes per week. Interestingly, 3 of the 20 CSB subjects mentioned to interviewers that they suffered from "orgasmic-erection disorder," while none of the control subjects reported sexual problems.

8) Brain Structure and Functional Connectivity Associated With Pornography Consumption: The Brain on Porn (2014) - A Max Planck study which found 3 significant addiction-related brain changes correlating with the amount of porn consumed. It also found that the more porn consumed the less reward circuit activity in response to brief exposure (.530 second) to vanilla porn. In a 2014 article lead author Simone Kühn said:

"We assume that subjects with a high porn consumption need increasing stimulation to receive the same amount of reward. That could mean that regular consumption of pornography more or less wears out your reward system. That would fit perfectly the hypothesis that their reward systems need growing stimulation."

A more technical description of this study from a review of the literature by Kuhn & Gallinat - Neurobiological Basis of Hypersexuality (2016).

"The more hours participants reported consuming pornography, the smaller the BOLD response in left putamen in response to sexual images. Moreover, we found that more hours spent watching pornography was associated with smaller gray matter volume in the striatum, more precisely in the right caudate reaching into the ventral putamen. We speculate that the brain structural volume deficit may reflect the results of tolerance after desensitization to sexual stimuli."

9) Sexual Desire, not Hypersexuality, is Related to Neurophysiological Responses Elicited by Sexual Images (2013) - This EEG study was touted in the media as evidence against the existence of porn addiction. Not so. In line with the Cambridge University brain scan studies, this EEG study reported greater cue-reactivity to porn correlated with less desire for partnered sex. To put another way - individuals with more brain activation and cravings for porn would rather masturbate to porn than have sex with a real person. Study spokesman Nicole Prause claimed that porn users merely had high libido, yet the results of the study say something quite different. Three peer-reviewed papers expose the truth: 1, 2, 3. Also see the extensive YBOP critique.

10) Modulation of Late Positive Potentials by Sexual Images in Problem Users and Controls Inconsistent with "Porn Addiction" (2015) - Another Nicole Prause EEG study. This time comparing the 2013 subjects from the above study to an actual control group. The results: compared to controls, "porn addicts" had less response to one-second exposure to photos of vanilla porn. The lead author, Nicole Prause, claimed these results debunk porn addiction. However, these findings align perfectly with Kühn & Gallinat (2014), which found that more porn use correlated with less brain activation in response to pictures of vanilla porn. Put simply, frequent porn users were desensitized and needed greater stimulation to achieve the same buzz. Four peer-reviewed papers say that Prause findings indicate desensitization, and addiction-related phenomenon: 1, 2, 3, 4 (also see this extensive YBOP critique). By the way, another EEG study found that greater porn use in women correlated with less brain activation to porn.

11) Unusual masturbatory practice as an etiological factor in the diagnosis and treatment of sexual dysfunction in young men (2014) – One of the 4 case studies in this paper reports on a man with porn-induced sexual problems (low libido, fetishes, anorgasmia). The sexual intervention called for a 6-week abstinence from porn and masturbation. After 8 months the man reported increased sexual desire, successful sex and orgasm, and enjoying “good sexual practices. This is the first peer-reviewed chronicling of a recovery from porn-induced sexual dysfunctions. Excerpts from the paper:

"When asked about masturbatory practices, he reported that in the past he had been masturbating vigorously and rapidly while watching pornography since adolescence. The pornography originally consisted mainly of zoophilia, and bondage, domination, sadism, and masochism, but he eventually got habituated to these materials and needed more hardcore pornography scenes, including transgender sex, orgies, and violent sex. He used to buy illegal pornographic movies on violent sex acts and rape and visualized those scenes in his imagination to function sexually with women. He gradually lost his desire and his ability to fantasize and decreased his masturbation frequency."

In conjunction with weekly sessions with a sex therapist, the patient was instructed to avoid any exposure to sexually explicit material, including videos, newspapers, books, and internet pornography.

After 8 months, the patient reported experiencing successful orgasm and ejaculation. He renewed his relationship with that woman, and they gradually succeeded in enjoying good sexual practices.

12) Erectile Dysfunction, Boredom, and Hypersexuality among Coupled Men from Two European Countries (2015) - Survey reported a strong correlation between erectile dysfunction and measures of hypersexuality. The study omitted correlation data between erectile functioning and pornography use, but noted a significant correlation. An excerpt:

Among Croatian and German men, hypersexuality was significantly correlated with proneness to sexual boredom and more problems with erectile function.

13) Masturbation and Pornography Use Among Coupled Heterosexual Men With Decreased Sexual Desire: How Many Roles of Masturbation? (2015) - Masturbating to porn was related with decreased sexual desire and low relationship intimacy. Excerpts:

"Among men who masturbated frequently, 70% used pornography at least once a week. A multivariate assessment showed that sexual boredom, frequent pornography use, and low relationship intimacy significantly increased the odds of reporting frequent masturbation among coupled men with decreased sexual desire."

"Among men [with decreased sexual desire] who used pornography at least once a week [in 2011], 26.1% reported that they were unable to control their pornography use. In addition, 26.7% of men reported that their use of pornography negatively affected their partnered sex and 21.1% claimed to have attempted to stop using pornography."

14) Use of pornography in a random sample of Norwegian heterosexual couples (2009) - Porn use was correlated with more sexual dysfunctions in the man and negative self perception in the female. The couples who did not use porn had no sexual dysfunctions. A few excerpts from the study:

In couples where only one partner used pornography, we found more problems related to arousal (male) and negative (female) self-perception.

In those couples where one partner used pornography there was a permissive erotic climate. At the same time, these couples seemed to have more dysfunctions.

The couples who did not use pornography... may be considered more traditional in relation to the theory of sexual scripts. At the same time, they did not seem to have any dysfunctions.

Couples who both reported pornography use grouped to the positive pole on the ‘‘Erotic climate’’ function and somewhat to the negative pole on the ‘‘Dysfunctions’’ function.

15) Lecture describing upcoming studies - by Urology professor Carlo Foresta, president of the Italian Society of Reproductive Pathophysiology - The lecture contains the results of longitudinal and cross-sectional studies. One study involved a survey of high school teens (pages 52-53). The study reported that sexual dysfunction doubled between 2005 and 2013, with low sexual desire increasing 600%.

  • The percentage of teens that experienced alterations of their sexuality: 2004/05: 7.2%, 2012/13: 14.5%
  • The percentage of teens with low sexual desire: 2004/05: 1.7%, 2012/13: 10.3% (that's a 600% increase in 8 years)

Foresta also describes his upcoming study, "Sexuality media and new forms of sexual pathology sample 125 young males, 19-25 years" (Italian name - "Sessualità mediatica e nuove forme di patologia sessuale Campione 125 giovani maschi"). The results from the study (pages 77-78), which used the International Index of Erectile Function Questionnaire, found that regular porn users scored 50% lower on sexual desire domain and 30% lower of the erectile functioning domain.

16) (not peer-reviewed) Here's an article about an extensive analysis of comments and questions posted on MedHelp concerning erectile dysfunction. What's shocking is that 58% of the men asking for help were 24 or younger. Many suspected that internet porn could be involved as described in the results from the study -

EXCERPT: The most common phrase is “erectile dysfunction” – which is mentioned more than three times as often as any other phrase – followed by “internet porn,” “performance anxiety,” and “watching porn.”

Clearly, porn is a frequently discussed subject: “I have been viewing internet pornography frequently (4 to 5 times a week) for the past 6 years,” one man writes. “I am in my mid-20s and have had a problem getting and maintaining an erection with sexual partners since my late teens when I first started looking at internet porn.

Reality check. All studies assessing young male sexuality since 2010 report historic levels of sexual dysfunctions, and startling rates of a new scourge: low libido. All documented in this article.

Erectile dysfunction rates ranged from 27 to 33%, while rates for low libido (hypo-sexuality) ranged from 16% to 37%. The lower ranges are taken from studies involving teens and men 25 and under, while the higher ranges are from studies involving men 40 and under.

Prior to the advent of free streaming porn, cross-sectional studies and meta-analysis consistently reported erectile dysfunction rates of 2-5% in men under 40. That's nearly a 1000% increase in youthful ED rates in the last 20 years. What variable has changed in the last 15 years that could account for this astronomical rise?


PFAUS: "These types of advocates are wedded to the idea that porn is an uncontrolled stimulus the brain gets addicted to because of the dopamine release it causes. According to their thinking, anything that causes dopamine release is addictive"

RESPONSE: A false statement by Pfaus. Of course, I never said that "anything that causes dopamine release is addictive". I'm guessing that Pfaus, of all researchers, realizes that sexual activity is a unique natural reward. Sexual activity induces the highest levels of nucleus accumbens dopamine naturally available. The same goes for endogenous opioids. In fact, Pfaus has published studies showing that sexual activity leads to conditioned place preference (CPP). CPP is used to assess the addictiveness of substances. Studies on rats have demonstrated that sex is a unique stimulus in that it activates the same reward system neurons as addictive drugs such as meth. By comparison, other natural rewards (food, water) may only overlap 10-20% with the sex/addictive drug neurons.

I suggest the following study, which compared the neurobiology of sexual activity with the neurobiology of sensitization to addictive drugs. (By the way sensitization is the core brain change involved in addiction, as proposed by the incentive motivation theory of addiction.) "Natural and Drug Rewards Act on Common Neural Plasticity Mechanisms with ΔFosB as a Key Mediator (2013)". An excerpt from conclusion:

"Thus, natural and drug rewards not only converge on the same neural pathway, they converge on the same molecular mediators, and likely in the same neurons in the nucleus to influence the incentive salience and the “wanting” of both types of rewards."

This means that addictive drugs and sex activity induce the same brain changes on the same neurons that lead to craving and wanting for IT, whether that IT is drugs or sex.


PFAUS: "For instance, according to proponents of the sex addiction industry, the more porn someone watches, the more they’ll experience erectile dysfunction."

RESPONSE: No so. It's already established in studies on both internet porn addiction (1, 2, 3) and internet video-gaming addiction, that symptoms do not correlate with "hours of use." Instead of just current hours of use, a combination of variables appear to correlate best with porn-induced ED. These may include:

  1. Ratio of masturbation to porn versus masturbation without porn
  2. Ratio of sexual activity with a person versus masturbation to porn
  3. Gaps in partnered sex (where one relies only on porn)
  4. Virgin or not
  5. Total hours of use
  6. Years of use
  7. Age started using porn
  8. Escalation to new genres
  9. Development of porn-induced fetishes (from escalating to new genres of porn)
  10. Level of novelty per session (i.e. compilation videos, multiple tabs)
  11. Addiction-related brain changes or not
  12. Presence of hypersexuality/porn addiction

The better way to research this phenomenon, is to remove the variable of internet porn use and observe the outcome. Such research reveals causation instead of correlations open to interpretation. My site has documented a few thousand men who removed porn and recovered from chronic sexual dysfunctions.


PFAUS: "However, my recent study with Nicole Prause, a psychophysiologist and neuroscientist at UCLA, showed that’s absurd. While advocates of sex and porn addiction are quick to correlate the amount of porn a guy looks at to how desensitized his penis is, our study showed that watching immense amounts of porn made men more sensitive to less explicit stimuli. Simply put, men who regularly watched porn at home were more aroused while watching porn in the lab than the men in the control group. They were able to get erections quicker and had no trouble maintaining them, even when the porn being watched was “vanilla” (i.e., free of hardcore sex acts like bondage)."

RESPONSE: Many of the above claims remain unsupported despite requests for evidence that they are true.

1) First, the paper wasn't a study at all. Instead Jim's co-author Prause claimed to have gathered data from four of her earlier studies, none of which had anything to do with erectile dysfunction. Jim Pfaus was not involved in those 4 earlier studies. The four underlying papers claimed to have assessed hours of porn use in the last month. No other variables related to porn use were examined.

2) None of the data from the Prause & Pfaus (2015) paper matched the four earlier studies. The discrepancies were not small and have not been explained. A comment by researcher Richard A. Isenberg MD, published in Sexual Medicine Open Access, points out several (but not all) of the discrepancies, errors, and unsupported claims.

3) Contrary to Pfaus's claims, the Prause & Pfaus paper did not assess erection quality in the lab or "speed of erections". Remember this was data from 4 earlier papers - none of which reported physiological assessment of erections in lab. The papers only asked guys to rate their "arousal," after briefly viewing porn (not to rate their erectile function). An excerpt from Prause & Pfaus (2015) clearly states that no genital responses were included:

"No physiological genital response data were included to support men’s self-reported experience."

Really get this: The men who watched more porn did NOT have better or stronger erections. There were no assessments of erections in the lab.

4) As Dr. Isenberg wondered, how is it possible for Prause & Pfaus to have compared different subject's arousal levels when three different types of sexual stimuli were used in the 4 underlying studies: Two studies used a 3-minute film, one study used a 20-second film, and one study used still images. It's well established that films are far more arousing than photos. What's shocking is that in this paper Prause & Pfaus claim that all 4 studies used sexual films:

"The VSS presented in the studies were all films."

Yet this was not the case.

5) Dr. Isenberg also asked how Prause & Pfaus compared different subject's arousal levels when only 1 of the 4 underlying studies used a 1 to 9 scale. One used a 0 to 7 scale, one used a 1 to 7 scale, and one study did not report sexual arousal ratings. Once again Prause & Pfaus inaccurately claim that:

"men were asked to indicate their level of “sexual arousal” ranging from 1 “not at all” to 9 “extremely.”

Yet this was not the case.

For argument sake let's say that men who watched more had slightly higher self reported arousal to porn. Another, more science-based, way to interpret this arousal difference is the men who used more porn experienced greater cravings to use porn. Interestingly, they had less desire for sex with a partner and more desire to masturbate than those who logged fewer hours watching porn. (Figure 2 in study). Increased cravings to watch could be evidence of sensitization, which is greater reward circuit (brain) activation and desire to use when exposed to (porn) cues. Sensitization can be a precursor to addiction.

Three Cambridge University fMRI studies have demonstrated sensitization in compulsive porn users. Participants' brains were hyper-aroused in response to porn video clips, even though they didn't "like" some of the sexual stimuli more than control participants. In a dramatic example of how sensitization can affect sexual performance, 60% of the Cambridge subjects reported arousal/erectile problems with partners, but not with porn. Simply put, craving to use porn tells us nothing about quality of erections when having sex with real persons.

Again, to understand the effects of internet pornography, trust addiction neuroscientists and their peer-reviewed papers.


Comments under the Pfaus article:

by Charles Samenow, MD, MPH, editor of Sexual Addiction and Compulsivity: The Journal of Treatment and Prevention:

It’s a shame that you destroy any credibility by citing things that are factually inaccurate. As the editor of Sexual Addiction and Compulsivity (note the title includes a broad approach to this disorder… and we continue to publish articles based on differing models including hypersexuality, problematic sexual behaviors, etc…) I can safely say that #1) we use external reviewers all the time and 2) our low impact factor has largely been due to the fact that for years we received almost no submissions due to the dearth of research in the area leading us to a very low rejection and circulation rate. Impact factor is not just related to number of citations. Finally, David Delmonico who was instrumental in the journal previously, actually has stepped down from the associate editor position due to inactivity over several years. So your insinuations that he is self-promoting are not only incorrect but quite frankly unprofessional. Quite ironic that you as an author who bases his whole critique on following research/science (or lack thereof) did not do his due diligence in reaching out to me or others to check his facts first. Any one of us on the editorial board or in SASH are always willing to dialogue, share, and keep an open mind. Are you?


Written by Frederick Toates, posted by Omakera

The following comments were written by a retired UK professor (Frederick Toates) who is the author of the recent book “How Sexual Desire Works: The Enigmatic Urge.” It is a comprehensive review of the relevant research in this field. These comments are posted with his permission:

Right at the outset, the author switches vocabulary from addiction, writing “…in fact, hypersexuality and porn obsessions are not addictions at all”. Of course, hypersexuality is not synonymous with addiction unless other criteria are also met but rephrasing addiction as obsession seems to me to be confusing. In a clinical context, obsession is a very different phenomenon from addiction, though sharing some features. I would invite anyone who feels that using ‘obsession’ in some way mitigates the impact to observe the bleeding hands of an OCD hand-washer and compare this with a kid told to put his smartphone away. 

 We are told that the guy denied his porn shows no sign of physical addiction. But what other kind of addiction is there that he might or might not show? This suggests a Cartesian split between body and mind, which modern neuroscience rejects. If Jim Pfaus means signs outside the brain/mind, then neither do many cocaine addicts show this.
 
 My reading of their books does not suggest to me that Wilson/Robinson do claim that “anything that causes dopamine release is addictive”. Dopamine is released all the time in all of us and I can’t believe that they are unaware of this. Surely their point is that under certain conditions dopamine release can be such as to increase incentive salience to the point of addiction.
 
 Jim Pfaus writes: “But there’s a difference between compulsion and addiction. Addiction can’t be stopped without major consequence, including new brain activity. Compulsive behavior can be stopped; it’s just difficult to do so”. The experience of US soldiers being offered discharge from Vietnam was that a change of circumstances could quickly undermine even heroin addiction (Robins). Doubtless there was new brain activity accompanying their discharge but so is there in a compulsive checker or hand-washer who heals (see Jeff Schwartz, UCLA). It is true that withdrawal from alcohol can be extremely dangerous without medical supervision but that does not mean that from a psychological perspective alcohol addiction should be put in a class all of its own. The idea that compulsive behaviour is simply “difficult” to stop is something of an understatement to put it mildly.
 
 Jim writes “Plenty of compulsive and ritualistic sexual behaviors aren’t addictions; they’re symptomatic of other issues”. But most if not all addictions can be symptomatic of other issues. See the brilliant work of Bruce Alexander and Gabor Mate on the triggering role of alienation and despair in drug addicts.
 
 Take the extreme case of a young man who masturbates until he has damaged his penis and who seeks help. I find it hard to see how it would enlighten him to be told that he is compelled but not addicted.
 
 Let me hasten to add that I am not writing from a religious perspective and neither do I stand to make a single cent from sexual addiction. I wrote what I thought was a balanced account of sexual addiction in a recent book and indeed it earned a very high praise from no less a dignitary than Jim Pfaus! (Please see link — http://www.amazon.com/How-Sexual-Desire-Works-Enigmatic/dp/1107688043/ref=sr_1_1?s=books&ie=UTF8&qid=1453918582&sr=1-1