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Peer-reviewed critiques of Prause et al., 2015


8) Online Porn Addiction: What We Know and What We Don’t—A Systematic Review (2019)

Excerpt critiquing Prause’s 2 EEG studies: Steele et al., 2013 & Prause et al., 2015 (citation 105 is Steele, citation 107 is Prause):

Evidence of this neural activity signalizing desire is particularly prominent in the prefrontal cortex [101] and the amygdala [102,103], being evidence of sensitization. Activation in these brain regions is reminiscent of financial reward [104] and it may carry a similar impact. Moreover, there are higher EEG readings in these users, as well as the diminished desire for sex with a partner, but not for masturbation to pornography [105], something that reflects also on the difference in erection quality [8]. This can be considered a sign of desensitization. However, Steele’s study contains several methodological flaws to consider (subject heterogeneity, a lack of screening for mental disorders or addictions, the absence of a control group, and the use of questionnaires not validated for porn use) [106]. A study by Prause [107], this time with a control group, replicated these very findings. The role of cue reactivity and craving in the development of cybersex addiction have been corroborated in heterosexual female [108] and homosexual male samples [109].

COMMENTS: The above critique states that Prause’s 2015 EEG replicated the findings from her 2013 EEG study (Steele et al.): Both studies reported evidence of habituation or desensitization, which is consistent with the addiction model (tolerance). Let me explain.

It’s important to know that Prause et al., 2015 AND Steele et al., 2013 had the same “porn addicted” subjects. The problem is that Steele et al.had no control group for comparison! So Prause et al., 2015 compared the 2013 subjects from Steele et al., 2013 to an actual control group (yet it suffered from the same methodological flaws named above). The results: Compared to controls “individuals experiencing problems regulating their porn viewing” had lower brain responses to one-second exposure to photos of vanilla porn. The ACTUAL results of Prause’s two EEG studies:

  1. Steele et al., 2013: Individuals with greater cue-reactivity to porn had less desire for sex with a partner, but not less desire to masturbate.
  2. Prause et al., 2015: “Porn addicted users” had less brain activation to static images of vanilla porn. Lower EEG readings mean that the “porn addicted” subjects were paying less attention to the pictures.

A clear pattern emerges from the 2 studies: The “porn addicted users” were desensitized or habituated to vanilla porn, and those with greater cue-reactivity to porn preferred to masturbate to porn than have sex with a real person. Put simply they were desensitized (a common indication of addiction) and preferred artificial stimuli to a very powerful natural reward (partnered sex). There is no way to interpret these results as falsifying porn addiction. The findings support the addiction model.


How to recognize biased articles: they cite Prause et al. 2015 (falsely claiming it debunks porn addiction), while omitting over 3 dozen neurological studies supporting porn addiction

A number of articles and interviews have attempted to pushback at the TIME article (“Porn and the Threat to Virility”) and the Utah resolution declaring internet porn a public health problem. What might be a few “dead giveaways” that such an article is nothing more than a propaganda piece?

  1. Psychologists David Ley and/or Nicole Prause are cited as “the experts,” while actual top addiction neuroscientists, who have published highly respected studies on porn users (Voon, Kraus, Potenza, Brand, Laier, Hajela, Kuhn, Gallinat, Klucken, Seok, Sohn, Gola, Banca, etc.), are omitted. Neither Ley nor Prause are affiliated with any university, yet some journalists, perhaps influenced by Prause’s potent media services, mysteriously prefer both over the top neuroscientists at Yale University, Cambridge University, University of Duisburg-Essen, and the Max Planck Institute. Go figure.
  2. The articles tend to cite Prause’s lone, anomalous 2015 brainwave (EEG) study as proof that porn addiction doesn’t exist, while simultaneously omitting 38 neurological studies and 18 recent reviews of the literature and commentaries: Current list of brain studies on porn users/sex addicts. (a few articles cite Prause’s 2013 EEG study, which, in fact, lends support to the porn addiction model and porn-induced sexual conditioning)
  3. The articles omit the 32 studies pointing to escalation & habituation in porn users (and even withdrawal symptoms).
  4. The articles omit 25 studies linking porn use to sexual problems and lower arousal to sexual stimuli (the first 5 studies in the list demonstrate causation, as participants eliminated porn use and healed chronic sexual dysfunctions).
  5. The articles omit over 65 studies linking porn use to less sexual satisfaction and poorer intimate relationships.
  6. The articles omit over 65 studies link porn use to poorer mental-emotional health & poorer cognitive outcomes.
  7. The articles omit over 25 studies linking porn use to “un-egalitarian attitudes” toward women
  8. The articles omit the many studies on adolescents, which report that porn use is related to such factors as poorer academics, more sexist attitudes, more aggression, poorer health, poorer relationships, lower life satisfaction, viewing people as objects, increased sexual risk taking, less condom use, greater sexual violence, unexplained anxiety, greater sexual coercion, less sexual satisfaction, lower libido, greater permissive attitudes, and a whole lot more.
  9. The articles falsely claim that porn addicts simply have a high libido, even though 25 studies have falsified this often repeated meme.
  10. In classic “astroturfing-style,” the articles engage in ad hominem attacks on those with opposing views (such as libelous claims of nonexistent “restraining-orders,” “stalking,” and religious and profit motives), without supplying objective proof of such claims.

Reality Check Concerning Prause’s 2015 EEG Study (Prause et al., 2015)

Prause’s 2015 EEG study (claiming to debunk porn addiction) actually supports the existence of porn addiction because her team found desensitization in the heavy porn users.

Compared to controls, more frequent porn users had lower brain activation to one-second exposure to photos of vanilla porn. The lead author, Nicole Prause claims these results debunk porn addiction. However, these findings align perfectly with Kühn & Gallinat (2014), which found that more porn use correlated with lower brain activation in response to pictures of vanilla porn (and less gray matter in the dorsal striatum). In other words, the frequent porn users were desensitized to still images and needed greater stimulation than occasional porn users. Seven peer-reviewed papers agree with the PSC analysis, namely that what Prause actually found is consistent with the effects of addiction in her study’s subjects:

  1. Neuroscience of Internet Pornography Addiction: A Review and Update – Excerpt critiquing Prause et al., 2015
  2. Neurobiology of Compulsive Sexual Behavior: Emerging Science (2016)
  3. Should compulsive sexual behavior be considered an addiction? (2016) – Excerpt analyzing Prause et al., 2015
  4. Decreased LPP for sexual images in problematic pornography users may be consistent with addiction models. Everything depends on the model. (Commentary on Prause, Steele, Staley, Sabatinelli, & Hajcak, 2015)
  5. Is Internet Pornography Causing Sexual Dysfunctions? A Review with Clinical Reports – Excerpt analyzing Prause et al., 2015
  6. Conscious and Non-Conscious Measures of Emotion: Do They Vary with Frequency of Pornography Use? (2016) – Excerpt analyzing Prause et al., 2015
  7. Neurocognitive mechanisms in compulsive sexual behavior disorder (2018) – Excerpts analyzing Prause et al., 2015
  8. Online Porn Addiction: What We Know and What We Don’t—A Systematic Review (2019): Excerpt analyzing Prause et al., 2015

Author of the second critique, neuroscientist Mateusz Gola, summed up it up nicely:

“Unfortunately the bold title of Prause et al. (2015) article has already had an impact on mass media, thus popularizing a scientifically unjustified conclusion.”

What legitimate researcher would ever claim to have debunked an entire field of research and to refute all previous studies with a single EEG study? (Close ties to the industry in question might cloud a researcher’s perceptions). Not only was the title scientifically unjustified, Nicole Prause claimed her study contained 122 subjects (N). In reality, the study had only 55 subjects who were “experiencing problems regulating their viewing of sexual images”. The subjects were recruited from Pocatello Idaho, which is over 50% Mormon. The other 67 participants were controls.

In a second dubious claim, Prause et al., 2015 stated in both the abstract and in the body of the study:

“These are the first functional physiological data of persons reporting VSS regulation problems”.

This is clearly not the case, as the Cambridge University fMRI study was published nearly a year earlier.

In a third claim Nicole Prause has consistently asserted that Prause et al., 2015 is the largest neuroscience study published on porn addiction. Two problems with this claim:

  1. It’s not a study on porn addiction if it has no porn addicts. This study, and 2 earlier Prause studies (Prause et al., 2013 & Steele et al., 2013) did not assess whether any of the subjects were porn addicts or not. Prause admitted in a an interview that many of the subjects had little difficulty controlling use. All of the subjects would have to have been confirmed porn addicts to permit a legitimate comparison with a group of non-porn addicts. Three of the five peer-reviewed critiques point out this fatal flaw.
  2. HPA axis dysregulation in men with hypersexual disorder (2015) is the largest neuroscience based study to date on “hypersexuals” (67 subjects).  The study assessed the brain’s response to stress by assessing a hormone release by the brain (ACTH), and a hormone controlled by the brain (cortisol). While this study was a published a few months after Prause et al., 2015, Nicole Prause continues to claim her EEG study as the largest.

You Can’t “Debunk Porn Addiction” If Your Subjects Are Not Porn Addicts

The 3 Prause Studies (Prause et al., 2013, Prause et al., 2015, Steele et al., 2013.) all involved the same subjects. Here’s what we know about the “porn addicted users” in Prause’s 3 studies (the “Prause Studies”): They were not necessarily addicts, as they were never assessed for porn addiction. Thus, they can’t legitimately be used to “falsify” anything to do with the addiction model. As a group they were desensitized or habituated to vanilla porn, which is consistent with predictions of the addiction model. Here’s what each study actually reported about the “porn addicted” subjects:

  1. Prause et al., 2013: “Porn addicted users” reported more boredom and distraction while viewing vanilla porn.
  2. Steele et al., 2013: Individuals with greater cue-reactivity to porn had less desire for sex with a partner, but not less desire to masturbate.
  3. Prause et al., 2015: “Porn addicted users” had less brain activation to static images of vanilla porn. Lower EEG readings mean that the “porn addicted” subjects were paying less attention to the pictures.

A clear pattern emerges from the three studies: The “porn addicted users” were desensitized or habituated to vanilla porn, and those with greater cue-reactivity to porn preferred to masturbate to porn than have sex with a real person. Put simply they were desensitized (a common indication of addiction) and preferred artificial stimuli to a very powerful natural reward (partnered sex). There is no way to interpret these results as falsifying porn addiction.

Make no mistake, neither Steele et al., 2013 nor Prause et al., 2015 described these 55 subjects as porn addicts or compulsive porn users. The subjects only admitted to feeling “distressed” by their porn use. Confirming the mixed nature of her subjects, Prause admitted in 2013 interview that some of the 55 subjects experienced only minor problems (which means they were not porn addicts):

“This study only included people who reported problems, ranging from relatively minor to overwhelming problems, controlling their viewing of visual sexual stimuli.”

Besides not establishing which of the subjects were porn addicted, the Prause Studies did not screen subjects for mental disorders, compulsive behaviors, current drug use, or other addictions. This is critically important for any “brain study” on addiction, lest confounds render results meaningless.

In summary, the 3 Prause Studies did not assess whether the subjects were porn addicts or not. The authors admitted that many of the subjects had little difficulty controlling use. All of the subjects would have to have been confirmed porn addicts to permit a legitimate comparison with a group of non-porn addicts.

In 2013 Prause Said That Less Brain Activation Would Indicate Habituation or Addiction

You read that correctly. Prause’s 2015 claim of “debunking porn addiction” represents a flip-flop from her 2013 study’s claim of “debunking porn addiction.”

In her 2013 EEG study and related blog post, Prause admits that reduced brain activation would indicate habituation or addiction, but claimed her subjects didn’t show reduced activation. This claim, however, was groundless as explained here. She had no control group, so she could not compare “porn addicts'” EEG readings to “non-addicts'” readings. As a result, her 2013 study told us nothing about the EEG readings for either healthy individuals or “hypersexuals.”

Finally, in 2015 she added control subjects and published a second study. Sure enough, her “porn addicted” subjects displayed reduced brain activation in comparison to controls – just as would be expected in porn users suffering from habituation or addiction. Undaunted by findings that undermined her 2013 conclusion, she boldly, and without any basis in science, claimed that her corrected findings – which were consistent with the presence of addiction – “dismantled porn addiction.” And this is the talking point these propaganda pieces latch onto, with no support other than Prause’s unfounded claims.

Let’s back up and look more closely at Prause’s views from her 2013 study (Steele et al.):

“Therefore, individuals with high sexual desire could exhibit large P300 amplitude difference between sexual stimuli and neutral stimuli due to salience and emotional content of the stimuli. Alternatively, little or no P300 amplitude difference could be measured due to habituation to VSS.

In 2013, Prause said that porn addicts, when compared to controls, could either exhibit:

  1. higher EEG readings due to cue-reactivity to images, or
  2. lower EEG readings due to habituation to porn (VSS).

Five months before her 2013 EEG study was published, Prause and David Ley teamed up to write this Psychology Today blog post about her upcoming 2013 study (and its unsupported claims). In it they admit that “diminished electrical response” would indicate habituation or desensitization:

“But, when EEG’s were administered to these individuals, as they viewed erotic stimuli, results were surprising, and not at all consistent with sex addiction theory. If viewing pornography actually was habituating (or desensitizing), like drugs are, then viewing pornography would have a diminished electrical response in the brain. In fact, in these results, there was no such response. Instead, the participants’ overall demonstrated increased electrical brain responses to the erotic imagery they were shown, just like the brains of “normal people”…

So, we have 2013 Prause saying “diminished electrical response” would indicate habituation or desensitization. Later, however, in 2015, when Prause added controls for comparison and found evidence of desensitization (common in addicts), she tells us “diminished electrical response” debunks porn addiction. Huh?

In the intervening two years it took Prause to compare her same tired subject data with an actual control group, she executed a complete flip-flop. In 2015, she claimed the evidence of desensitization that she found when she added the control group isn’t evidence of addiction (which she claimed in 2013 it would have been). Instead, evidence of desensitization now (magically) “disproves addiction” (even though it aligns with addiction perfectly). This is inconsistent and unscientific, and suggests that regardless of opposing findings, she will always claim to have “disproven addiction.”

What About Brain Studies That Falsify Porn Addiction?

There are none (really). This page lists all the studies assessing the brain structure and functioning of internet porn users. To date, every study offers support for the porn addiction model (including Prause’s two studies just discussed). However, whenever an article claiming to debunk porn addiction cites a study, I expect you will find one of her two EEG studies, or an irresponsible “review” by Prause, Ley and Finn. Here they are for easy reference:

  1. Sexual Desire, not Hypersexuality, is Related to Neurophysiological Responses Elicited by Sexual Images (Steele et al., 2013)
  2. Modulation of Late Positive Potentials by Sexual Images in Problem Users and Controls Inconsistent with “Porn Addiction” (Prause et al., 2015)
  3. The Emperor Has No Clothes: A Review of the ‘Pornography Addiction’ Model, by David Ley, Nicole Prause & Peter Finn (Ley et al., 2014)

Kinsey Institute grad Nicole Prause is the lead author on studies 1 and 2, and is the second author on paper #3. We already saw above that study #2 (Prause et al., 2015) lends support to the porn addiction model. But how does Prause’s 2013 EEG study (Steele et al., 2013), touted in the media as evidence against the existence of porn addiction, actually support the porn addiction model?

This study’s only significant finding was that individuals with greater cue-reactivity to porn had less desire for sex with a partner (but not lower desire to masturbate to porn). Put another way, individuals with more brain activation and cravings for porn would rather masturbate to porn than have sex with a real person. This is typical of addicts, not healthy subjects.

Study spokesman Nicole Prause claimed that frequent porn users merely had high libido, yet the results of the study say something quite different. As Valerie Voon (and 10 other neuroscientists) explained, Prause’s 2013 findings of greater cue-reactivity to porn coupled with lower desire for sex with real partners aligned with their 2014 brain scan study on porn addicts. Put simply, the actual findings of the 2013 EEG study in no way match the unsupported “debunking” headlines. Seven peer-reviewed papers expose the truth about this earlier study by Prause’s team: 1, 2, 3, 4, 5, 6, 7.

As a side note, this same 2013 study reported higher EEG readings (P300) when subjects were exposed to porn photos. Studies consistently show that an elevated P300 occurs when addicts are exposed to cues (such as images) related to their addiction. This finding supports the porn addiction model, as the above peer-reviewed papers explained and psychology professor emeritus John A. Johnson pointed out in a comment under a 2013 Psychology Today Prause interview:

My mind still boggles at the Prause claim that her subjects’ brains did not respond to sexual images like drug addicts’ brains respond to their drug, given that she reports higher P300 readings for the sexual images. Just like addicts who show P300 spikes when presented with their drug of choice. How could she draw a conclusion that is the opposite of the actual results?

Dr. Johnson, who has no opinion on sex addiction, commented a second time under the Prause interview:

Mustanski asks, “What was the purpose of the study?” And Prause replies, “Our study tested whether people who report such problems [problems with regulating their viewing of online erotica] look like other addicts from their brain responses to sexual images.”

But the study did not compare brain recordings from persons having problems regulating their viewing of online erotica to brain recordings from drug addicts and brain recordings from a non-addict control group, which would have been the obvious way to see if brain responses from the troubled group look more like the brain responses of addicts or non-addicts…..

Aside from the many unsupported claims in the press, it’s disturbing that Prause’s 2013 EGG study passed peer-review, as it suffered from serious methodological flaws:

  1. subjects were heterogeneous (males, females, non-heterosexuals);
  2. subjects were not screened for mental disorders or addictions;
  3. study had no control group for comparison;
  4. questionnaires were not validated for porn addiction.

The third paper listed above is not a study at all. Instead, it poses as an impartial “review of the literature” on porn addiction and porn’s effects. Nothing could be farther from the truth. The lead author, David Ley, is the author of The Myth of Sex Addiction and Nicole Prause is its second author. Ley & Prause not only teamed up to write paper #3, they also teamed up to write a Psychology Today blog post about paper #1. The blog post appeared 5 months before Prause’s paper was formally published (so no one could refute it). You may have seen Ley’s blog post with the oh-so-catchy title: “Your Brain on Porn – It’s NOT Addictive”. Ley zealously denies both sex and porn addiction. He has written 20 or so blog posts attacking porn-recovery forums, and dismissing porn addiction and porn-induced ED. He is not an addiction scientist, but rather a clinical psychologist, and like Prause is not associated with any university or research institute. Read more about Ley & Prause and their collaborations here.

The following is a very long analysis of paper #3, which goes line-by-line, showing all the shenanigans Ley & Prause incorporated in their “review”: The Emperor Has No Clothes: A Fractured Fairytale Posing As A Review. It completely dismantles the so-called review, and documents dozens of misrepresentations of the research they cited. The most shocking aspect of the Ley review is that it omitted ALL the many studies that reported negative effects related to porn use or found porn addiction!

Yes, you read that right. While purporting to write an “objective” review, Ley & Prause justified omitting hundreds of studies on the grounds that these were correlational studies. Guess what? Virtually all studies on porn are correlational, even those they cited, or misused. There are, and pretty much will be, only correlational studies, because researchers have no way to prove causation by comparing users with “porn virgins” or by keeping subjects off of porn for extended periods in order compare effects. (Thousands of guys are quitting porn voluntarily on various forums, however, and their results suggest that removing internet porn is the key variable in their symptoms and recoveries.)

Inherent Bias?

It’s unprecedented for a legitimate researcher to claim that their lone anomalous study has debunked a hypothesis supported by multiple neurological studies and decades of relevant research. Moreover, what legitimate researcher would be constantly tweeting that has debunked porn addiction? What legitimate researcher would personally attack young men who run porn-recovery forums? What’s going on here? By her own admission, rejects the concept of porn addiction. For example, a quote from this recent Martin Daubney article about sex/porn addictions:

Dr Nicole Prause, principal investigator at the Sexual Psychophysiology and Affective Neuroscience (Span) Laboratory in Los Angeles, calls herself a “professional debunker” of sex addiction.

In addition, Nicole Prause’s former Twitter slogan suggests she may lack the impartiality required for scientific research:

“Studying why people choose to engage in sexual behaviors without invoking addiction nonsense”

Updates on Nicole Prause’s twitter slogan:

  1. UCLA did not renew Prause’s contract. She hasn’t been affiliated with any university since early 2015.
  2. In October, 2015 Prause’s original Twitter account is permanently suspended for harassment

While many articles continue to describe Prause as a UCLA researcher, she hasn’t been employed by any university since the beginning of 2015. Finally, it’s important to know that the enterprising Prause offered (for a fee) her “expert” testimony against sex addiction and porn addiction. It seems as though Prause is attempting to sell her services to profit from the unsupportable anti-porn addiction conclusions of her two EEG studies (1, 2), even though 9 peer-reviewed analyses say both studies support the addiction model.

Interestingly, David Ley also profits from denying sex and porn addiction. At the end of this Psychology Today blog post Ley states:

Disclosure: David Ley has provided testimony in legal cases involving claims of sex addiction.

Ley also makes money selling two books which deny sex and porn addiction (“The Myth of Sex Addiction“, 2012 and “Ethical Porn for Dicks“, 2016). Pornhub is one of the four Amazon.com endorsements listed for Ley’s 2016 book.

Dismantling The Naysayers’ Talking Points

If you want a quick refutation of the naysayers’ pseudoscientific claims that they have “dismantled porn addiction,” watch Gabe Deem’s video: PORN MYTHS – The Truth Behind Addiction And Sexual Dysfunctions.

The following articles cite numerous studies, furnish illustrative examples, and elaborate logical arguments to dismantle many common anti-porn addiction propaganda talking points:

This section collects studies about which many experts have reservations – Questionable & Misleading Studies. In some, the methodology raises concerns. In others, the conclusions appear inadequately supported. In others, the title or terminology used is misleading given the actual study results. Some grossly misrepresent the actual findings.

All the Neuroscience Supports the Porn Addiction Model

Listed below are all the studies assessing the brain structure and functioning of Internet porn users (even the one claiming to have debunked porn addiction). To date every study offers support for the porn addiction model. The results of these 40 studies (and upcoming studies) are consistent with 260+ Internet addiction brain studies, many of which also include internet porn use. All support the premise that internet porn use can cause addiction-related brain changes, as do recent neuroscience-based reviews of the literature:

  1. Neuroscience of Internet Pornography Addiction: A Review and Update (2015). The review also critiques two recent headline-grabbing EEG studies which purport to have “debunked” porn addiction.
  2. Sex Addiction as a Disease: Evidence for Assessment, Diagnosis, and Response to Critics (2015), which provides a chart that takes on specific criticisms and offers citations that counter them.
  3. Neurobiology of Compulsive Sexual Behavior: Emerging Science (2016) Excerpt: “Given some similarities between CSB and drug addictions, interventions effective for addictions may hold promise for CSB, thus providing insight into future research directions to investigate this possibility directly.”
  4. Should Compulsive Sexual Behavior be Considered an Addiction? (2016) Excerpt: “Overlapping features exist between CSB and substance use disorders. Common neurotransmitter systems may contribute to CSB and substance use disorders, and recent neuroimaging studies highlight similarities relating to craving and attentional biases. Similar pharmacological and psychotherapeutic treatments may be applicable to CSB and substance addictions”
  5. Neurobiological Basis of Hypersexuality (2016). Excerpt: “Taken together, the evidence seems to imply that alterations in the frontal lobe, amygdala, hippocampus, hypothalamus, septum, and brain regions that process reward play a prominent role in the emergence of hypersexuality. Genetic studies and neuropharmacological treatment approaches point at an involvement of the dopaminergic system.
  6. Compulsive Sexual Behaviour as a Behavioural Addiction: The Impact of the Internet and Other Issues (2016)  Excerpts: “more emphasis is needed on the characteristics of the internet as these may facilitate problematic sexual behaviour.” and “clinical evidence from those who help and treat such individuals should be given greater credence by the psychiatric community.”
  7. Cybersex Addiction (2015) Excerpts: In recent articles, cybersex addiction is considered a specific type of Internet addiction. Some current studies investigated parallels between cybersex addiction and other behavioral addictions, such as Internet Gaming Disorder. Cue-reactivity and craving are considered to play a major role in cybersex addiction. Neuroimaging studies support the assumption of meaningful commonalities between cybersex addiction and other behavioral addictions as well as substance dependency.
  8. Searching for clarity in muddy water: future considerations for classifying compulsive sexual behavior as an addiction (2016) – Excerpts: We recently considered evidence for classifying compulsive sexual behavior (CSB) as a non-substance (behavioral) addiction. Our review found that CSB shared clinical, neurobiological and phenomenological parallels with substance-use disorders. Although the American Psychiatric Association rejected hypersexual disorder from DSM-5, a diagnosis of CSB (excessive sex drive) can be made using ICD-10. CSB is also being considered by ICD-11.
  9. Is Internet Pornography Causing Sexual Dysfunctions? A Review with Clinical Reports (2016) – An extensive review of the literature related to porn-induced sexual problems. Involving US Navy doctors, the review provides the latest data revealing a tremendous rise in youthful sexual problems. It also reviews the neurological studies related to porn addiction and sexual conditioning via Internet porn. The doctors provide 3 clinical reports of men who developed porn-induced sexual dysfunctions.
  10. Integrating psychological and neurobiological considerations regarding the development and maintenance of specific Internet-use disorders: An Interaction of Person-Affect-Cognition-Execution model (2016) – A review of the mechanisms underlying the development and maintenance of specific Internet-use disorders, including “Internet-pornography-viewing disorder”. The authors suggest that pornography addiction (and cybersex addiction) be classified as internet use disorders and placed with other behavioral addictions under substance-use disorders as addictive behaviors.
  11. Sexual Addiction chapter from Neurobiology of Addictions, Oxford Press (2016) – Excerpt: We review the neurobiological basis for addiction, including natural or process addiction, and then discuss how this relates to our current understanding of sexuality as a natural reward that can become functionally “unmanageable” in an individual’s life.
  12. Neuroscientific Approaches to Online Pornography Addiction (2017) – Excerpt: In the last two decades, several studies with neuroscientific approaches, especially functional magnetic resonance imaging (fMRI), were conducted to explore the neural correlates of watching pornography under experimental conditions and the neural correlates of excessive pornography use. Given previous results, excessive pornography consumption can be connected to already known neurobiological mechanisms underlying the development of substance-related addictions.
  13.  Is excessive sexual behaviour an addictive disorder? (Potenza et al., 2017) – Excerpts: Compulsive sexual behaviour disorder seems to fit well with non-substance addictive disorders proposed for ICD-11, consistent with the narrower term of sex addiction currently proposed for compulsive sexual behaviour disorder on the ICD-11 draft website. We believe that classification of compulsive sexual behaviour disorder as an addictive disorder is consistent with recent data and might benefit clinicians, researchers, and individuals suffering from and personally affected by this disorder.
  14. The Proof of the Pudding Is in the Tasting: Data Are Needed to Test Models and Hypotheses Related to Compulsive Sexual Behaviors (2018) – Excerpts: Among the domains that may suggest similarities between CSB and addictive disorders are neuroimaging studies, with several recent studies omitted by Walton et al. (2017). Initial studies often examined CSB with respect to models of addiction (reviewed in Gola, Wordecha, Marchewka, & Sescousse, 2016b; Kraus, Voon, & Potenza, 2016b).
  15. Promoting educational, classification, treatment, and policy initiatives Commentary on: Compulsive sexual behaviour disorder in the ICD-11 (Kraus et al., 2018) – Excerpts: The current proposal of classifying CSB disorder as an impulse-control disorder is controversial as alternate models have been proposed (Kor, Fogel, Reid, & Potenza, 2013). There are data suggesting that CSB shares many features with addictions (Kraus et al., 2016), including recent data indicating increased reactivity of reward-related brain regions in response to cues associated with erotic stimuli (Brand, Snagowski, Laier, & Maderwald, 2016; Gola, Wordecha, Marchewka, & Sescousse, 2016; Gola et al., 2017; Klucken, Wehrum-Osinsky, Schweckendiek, Kruse, & Stark, 2016; Voon et al., 2014.
  16. Compulsive Sexual Behavior in Humans and Preclinical Models (2018) – Excerpts: Compulsive sexual behavior (CSB) is widely regarded as a “behavioral addiction,” and is a major threat to quality of life and both physical and mental health. In conclusion, this review summarized the behavioral and neuroimaging studies on human CSB and comorbidity with other disorders, including substance abuse. Together, these studies indicate that CSB is associated with functional alterations in dorsal anterior cingulate and prefrontal cortex, amygdala, striatum, and thalamus, in addition to decreased connectivity between amygdala and prefrontal cortex.
  17. Sexual Dysfunctions in the Internet Era (2018) – Excerpt: Among behavioral addictions, problematic Internet use and online pornography consumption are often cited as possible risk factors for sexual dysfunction, often with no definite boundary between the two phenomena. Online users are attracted to Internet pornography because of its anonymity, affordability, and accessibility, and in many cases its usage could lead users through a cybersex addiction: in these cases, users are more likely to forget the “evolutionary” role of sex, finding more excitement in self-selected sexually explicit material than in intercourse.
  18. Neurocognitive mechanisms in compulsive sexual behavior disorder (2018) – Excerpt: To date, most neuroimaging research on compulsive sexual behavior has provided evidence of overlapping mechanisms underlying compulsive sexual behavior and non-sexual addictions. Compulsive sexual behavior is associated with altered functioning in brain regions and networks implicated in sensitization, habituation, impulse dyscontrol, and reward processing in patterns like substance, gambling, and gaming addictions. Key brain regions linked to CSB features include the frontal and temporal cortices, amygdala, and striatum, including the nucleus accumbens.
  19. A Current Understanding of the Behavioral Neuroscience of Compulsive Sexual Behavior Disorder and Problematic Pornography Use – Excerpt: Recent neurobiological studies have revealed that compulsive sexual behaviors are associated with altered processing of sexual material and differences in brain structure and function. Although few neurobiological studies of CSBD have been conducted to date, existing data suggest neurobiological abnormalities share communalities with other additions such as substance use and gambling disorders. Thus, existing data suggest that its classification may be better suited as a behavioral addiction rather than an impulse-control disorder.
  20. Ventral Striatal Reactivity in Compulsive Sexual Behaviors (2018) – Excerpt: Among currently available studies, we were able to find nine publications (Table 1) which utilized functional magnetic resonance imaging. Only four of these (3639) directly investigated processing of erotic cues and/or rewards and reported findings related to ventral striatum activations. Three studies indicate increased ventral striatal reactivity for erotic stimuli (3639) or cues predicting such stimuli (3639). These findings are consistent with Incentive Salience Theory (IST) (28), one of the most prominent frameworks describing brain functioning in addiction.
  21. Online Porn Addiction: What We Know and What We Don’t—A Systematic Review (2019) – Excerpt: As far as we know, a number of recent studies support this entity as an addiction with important clinical manifestations such as sexual dysfunction and psychosexual dissatisfaction. Most of the existing work is based off on similar research done on substance addicts, based on the hypothesis of online pornography as a ‘supranormal stimulus’ akin to an actual substance that, through continued consumption, can spark an addictive disorder.

See Questionable & Misleading Studies for highly publicized papers that are not what they claim to be.

See this page for the many studies linking porn use to sexual problems and decreased sexual & relationship satisfaction

“Brain Studies” (fMRI, MRI, EEG, Neuro-endocrine):

  1. Brain Structure and Functional Connectivity Associated With Pornography Consumption: The Brain on Porn (2014) – This Max Planck Institute fMRI study found less gray matter in the reward system (dorsal striatum) correlating with the amount of porn consumed. It also found that more porn use correlated with less reward circuit activation while briefly viewing sexual photos. Researchers believed their findings indicated desensitization, and possibly tolerance, which is the need for greater stimulation to achieve the same high. The study also reported that more porn viewing was linked to poorer connections between the reward circuit and prefrontal cortex – a common addiction-related brain change.
  2. Neural Correlates of Sexual Cue Reactivity in Individuals with and without Compulsive Sexual Behaviours (2014) – The first in a series of Cambridge University studies found the same brain activity as seen in drug addicts and alcoholics. It also found that porn addicts (CSB subjects) 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, yet could achieve erections with porn.
  3. Enhanced Attentional Bias towards Sexually Explicit Cues in Individuals with and without Compulsive Sexual Behaviours (2014) – The second Cambridge University study. An excerpt: “Our findings of enhanced attentional bias… suggest possible overlaps with enhanced attentional bias observed in studies of drug cues in disorders of addictions. These findings converge with recent findings of neural reactivity to sexually explicit cues in [porn addicts] in a network similar to that implicated in drug-cue-reactivity studies and provide support for incentive motivation theories of addiction underlying the aberrant response to sexual cues in [porn addicts].
  4. Novelty, Conditioning and Attentional Bias to Sexual Rewards (2015) – Compared to controls porn addicts preferred sexual novelty and conditioned cues associated porn. However, the brains of porn addicts habituated faster to sexual images. Since novelty preference wasn’t pre-existing, porn addiction drives novelty-seeking in an attempt to overcome habituation and desensitization.
  5. Neural Substrates of Sexual Desire in Individuals with Problematic Hypersexual Behavior (2015) – This Korean fMRI study replicates other brain studies on porn users. Like the Cambridge University studies it found cue-induced brain activation patterns in sex addicts which mirrored the patterns of drug addicts. In line with several German studies it found alterations in the prefrontal cortex which match the changes observed in drug addicts.
  6. 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/sex addiction. Not so. This SPAN Lab study, like #7 below, actually lends support to the existence of both porn addiction and porn use downregulating sexual desire. How so? The study reported higher EEG readings (P300) when subjects were briefly exposed to pornographic photos. Studies consistently show that an elevated P300 occurs when addicts are exposed to cues (such as images) related to their addiction. However, due to methodological flaws the findings are uninterpretable: 1) subjects were heterogeneous (males, females, non-heterosexuals); 2) subjects were not screened for mental disorders or addictions; 3) the study had no control group for comparison; 4) the questionnaires were not validated for porn addiction. In line with the Cambridge University brain scan studies, this EEG study also reported greater cue-reactivity to porn correlating with less desire for partnered sex. To put another way – individuals with greater brain activation to porn would rather masturbate to porn than have sex with a real person. Shockingly, study spokesman Nicole Prause claimed that porn users merely had “high libido”, yet the results of the study say something quite different. Four peer-reviewed papers expose the truth: 1, 2, 3, 4, 5.   Read an extensive critique here.
  7. Modulation of Late Positive Potentials by Sexual Images in Problem Users and Controls Inconsistent with “Porn Addiction” (2015) – Another SPAN Lab EEG study comparing the 2013 subjects from the above study to an actual control group. The results: compared to controls porn addicts had less response to photos of vanilla porn. Ignoring all the other studies on this page, lead author Nicole Prause, boldly claims that her results “debunked porn addiction”. What legitimate scientist would claim that their lone anomalous study has debunked an entire field of study?  In reality, the findings of Prause et al. 2015 align perfectly with Kühn & Gallinat (2014), which found that more porn use correlated with less brain activation in response to pictures of vanilla porn. Prause’s findings also align with Banca et al. 2015 which is #4 in this list. Moreover, another EEG study found that greater porn use in women correlated with less brain activation to porn. Lower EEG readings mean that subjects are paying less attention to the pictures. Put simply, frequent porn users were desensitized to static images of vanilla porn. They were bored. Read an extensive critique here. Six peer-reviewed papers agree with this critique of the study – 1, 2, 3, 4, 5, 6.
  8. HPA axis dysregulation in men with hypersexual disorder (2015) – A study with 67 male sex addicts and 39 age-matched controls. The Hypothalamus-Pituitary-Adrenal (HPA) axis is the central player in our stress response. Addictions alter the brain’s stress circuits leading to a dysfunctional HPA axis. This study on sex addicts (hypersexuals) found altered stress responses that mirror drug addiction.
  9. The Role of Neuroinflammation in the Pathophysiology of Hypersexual Disorder (2016) – This study reported higher levels of circulating Tumor Necrosis Factor (TNF) in sex addicts when compared to healthy controls. Elevated levels of TNF (a marker of inflammation) have also been found in substance abusers and drug addicted animals (alcohol, heroin, meth). There were strong correlations between TNF levels and rating scales measuring hypersexuality.
  10. Methylation of HPA Axis Related Genes in Men With Hypersexual Disorder (2017) – This is a follow-up of #8 above which found that sex addicts have dysfunctional stress systems – a key neuro-endocrine change caused by addiction. The current study found epigenetic changes on genes central to the human stress response and closely associated with addiction. With epigenetic changes, the DNA sequence isn’t altered (as happens with a mutation). Instead, the gene is tagged and its expression is turned up or down (short video explaining epigenetics). The epigenetic changes reported in this study resulted in altered CRF gene activity. CRF is a neurotransmitter and hormone that drives addictive behaviors such as cravings, and is a major player in many of the withdrawal symptoms experienced in connection with substance and behavioral addictions, including porn addiction.
  11. Compulsive sexual behavior: Prefrontal and limbic volume and interactions (2016) – Compared to healthy controls CSB subjects (porn addicts) had increased left amygdala volume and reduced functional connectivity between the amygdala and dorsolateral prefrontal cortex DLPFC. Reduced functional connectivity between the amygdala and the prefrontal cortex aligns with substance addictions. It is thought that poorer connectivity diminishes the prefrontal cortex’s control over a user’s impulse to engage in the addictive behavior. This study suggests that drug toxicity may lead to less gray matter and thus reduced amygdala volume in drug addicts. The amygdala is consistently active during porn viewing, especially during initial exposure to a sexual cue. Perhaps the constant sexual novelty and searching and seeking leads to a unique effect on the amygdala in compulsive porn users. Alternatively, years of porn addiction and severe negative consequences is very stressful – and chronic social stress is related to increased amygdala volume. Study #8 above found that “sex addicts” have a overactive stress system. Could the chronic stress related to porn/sex addiction, along with factors that make sex unique, lead to greater amygdala volume?
  12. Ventral striatum activity when watching preferred pornographic pictures is correlated with symptoms of Internet pornography addiction (2016) – Finding #1: Reward center activity (ventral striatum) was higher for preferred pornographic pictures. Finding #2: Ventral striatum reactivity correlated with the internet sex addiction score. Both findings indicate sensitization and align with the addiction model. The authors state that the “Neural basis of Internet pornography addiction is comparable to other addictions.
  13. Altered Appetitive Conditioning and Neural Connectivity in Subjects With Compulsive Sexual Behavior (2016) – A German fMRI study replicating two major findings from Voon et al., 2014 and Kuhn & Gallinat 2014. Compared to controls compulsive porn users had 1) greater conditioned cue-induced activity in the amygdala, while having 2) decreased coupling between the ventral striatum and the prefrontal cortex. Number 1 indicates sensitization, while number 2 indicates hypofronatlity. In addition, 3 of the 20 compulsive porn users suffered from “orgasmic-erection disorder”.
  14. Compulsivity across the pathological misuse of drug and non-drug rewards (2016) – A Cambridge University study comparing aspects of compulsivity in alcoholics, binge-eaters, video game addicts and porn addicts (CSB). Excerpts: CSB subjects were faster to learning from rewards in the acquisition phase compared to healthy volunteers and were more likely to perseverate or stay after either a loss or a win in the Reward condition. These findings converge with our previous findings of enhanced preference for stimuli conditioned to either sexual or monetary outcomes, overall suggesting enhanced sensitivity to rewards (Banca et al., 2016).
  15. Can pornography be addictive? An fMRI study of men seeking treatment for problematic pornography use (2017) – Excerpts: Men with and without problematic porn sue (PPU) differed in brain reactions to cues predicting erotic pictures, but not in reactions to erotic pictures themselves, consistent with the incentive salience theory of addictions. This brain activation was accompanied by increased behavioral motivation to view erotic images (higher ‘wanting’). Ventral striatal reactivity for cues predicting erotic pictures was significantly related to the severity of PPU, amount of pornography use per week and number of weekly masturbations. Our findings suggest that like in substance-use and gambling disorders the neural and behavioral mechanisms linked to anticipatory processing of cues relate importantly to clinically relevant features of PPU. These findings suggest that PPU may represent a behavioral addiction and that interventions helpful in targeting behavioral and substance addictions warrant consideration for adaptation and use in helping men with PPU.
  16. Conscious and Non-Conscious Measures of Emotion: Do They Vary with Frequency of Pornography Use? (2017) – Study assessed porn user’s responses (EEG readings & Startle Response) to various emotion-inducing images – including erotica. The study found several neurological  differences between low frequency porn users and high frequency porn users. An excerpt: Findings suggest that increased pornography use appears to have an influence on the brain’s non-conscious responses to emotion-inducing stimuli which was not shown by explicit self-report.
  17. Preliminary investigation of the impulsive and neuroanatomical characteristics of compulsive sexual behavior (2009) – Primarily sex addicts. Study reports more impulsive behavior in a Go-NoGo task in sex addicts (hypersexuals) compared to control participants. Brain scans revealed that sex addicts had greater disorganized prefrontal cortex white matter. This finding is consistent with “hypofrontality”, a hallmark of addiction.
  18. Pornography Addiction Detection based on Neurophysiological Computational Approach (2018) Excerpt: In this paper, a method of using brain signal from frontal area captured using EEG is proposed to detect whether the participant may have porn addiction or otherwise. Experimental results show that the addicted participants had low alpha waves activity in the frontal brain region compared to non-addicted participants. The theta band also show there is disparity between addicted and non-addicted. However, the distinction is not as obvious as alpha band.
  19. Gray matter deficits and altered resting-state connectivity in the superior temporal gyrus among individuals with problematic hypersexual behavior (2018) – fMRI study. Summary: …study showed gray matter deficits and altered functional connectivity in the temporal gyrus among individuals with PHB (sex addicts). More importantly, the diminished structure and functional connectivity were negatively correlated with the severity of PHB. These findings provide new insights into the underlying neural mechanisms of PHB.
  20. Altered Prefrontal and Inferior Parietal Activity During a Stroop Task in Individuals With Problematic Hypersexual Behavior (Seok & Sohn, 2018) – [poorer executive control- impaired PFC functionality. Excerpt: Our findings suggest that individuals with PHB have diminished executive control and impaired functionality in the right DLPFC and inferior parietal cortex, providing a neural basis for PHB.

The above studies are all the “brain studies” published (or in the press) on internet porn users.

Together these brain studies found:

  1. The 3 major addiction-related brain changes: sensitization, desensitization, and hypofrontality.
  2. More porn use correlated with less grey matter in the reward circuit (dorsal striatum).
  3. More porn use correlated with less reward circuit activation when viewing sexual images.
  4. More porn use correlated with disrupted neural connections between the reward circuit and prefrontal cortex.
  5. Addicts had greater prefrontal activity to sexual cues, but less brain activity to normal stimuli (matches drug addiction).
  6. Porn addicts have greater preference for sexual novelty yet their brains habituated faster to sexual images. Not pre-existing.
  7. 60% of compulsive porn addicted subjects in one study experienced ED or low libido with partners, but not with porn: all stated that internet porn use caused their ED/low libido.
  8. Enhanced attentional bias comparable to drug users. Indicates sensitization (a product of DeltaFosb).
  9. Greater wanting & craving for porn, but not greater liking. This aligns with the accepted model of addiction – incentive sensitization.
  10. The younger the porn users the greater the cue-induced reactivity in the reward center.
  11. Higher EEG (P300) readings when porn users were exposed to porn cues (which occurs in other addictions).
  12. Less desire for sex with a person correlating with greater cue-reactivity to porn images.
  13. More porn use related with lower LPP amplitude when viewing sexual photos: indicates habituation or desensitization.
  14. Dysfunctional HPA axis which reflects altered brain stress circuits (and greater amygdala volume, which is associated with chronic social stress).
  15. Epigenetic changes on genes central to the human stress response and closely associated with addiction.
  16. Higher levels of Tumor Necrosis Factor (TNF) – which also occurs in drug abuse and addiction.
  17. A deficit in temporal cortex gray matter; poorer connectivity between temporal corporate and several other regions

Neuro-Psychological Studies on Porn Users (with excerpts):

  1. Self-reported differences on measures of executive function and hypersexual behavior in a patient and community sample of men (2010) Patients seeking help for hypersexual behavior often exhibit features of impulsivity, cognitive rigidity, poor judgment, deficits in emotion regulation, and excessive preoccupation with sex. Some of these characteristics are also common among patients presenting with neurological pathology associated with executive dysfunction. These observations led to the current investigation of differences between a group of hypersexual patients (n = 87) and a non-hypersexual community sample (n = 92) of men using the Behavior Rating Inventory of Executive Function-Adult Version  Hypersexual behavior was positively correlated with global indices of executive dysfunction and several subscales of the BRIEF-A. These findings provide preliminary evidence supporting the hypothesis that executive dysfunction may be implicated in hypersexual behavior.
  2. Watching Pornographic Pictures on the Internet: Role of Sexual Arousal Ratings and Psychological-Psychiatric Symptoms for Using Internet Sex Sites Excessively (2011) Results indicate that self-reported problems in daily life linked to online sexual activities were predicted by subjective sexual arousal ratings of the pornographic material, global severity of psychological symptoms, and the number of sex applications used when being on Internet sex sites in daily life, while the time spent on Internet sex sites (minutes per day) did not significantly contribute to explanation of variance in IATsex score. We see some parallels between cognitive and brain mechanisms potentially contributing to the maintenance of excessive cybersex and those described for individuals with substance dependence
  3. Pornographic picture processing interferes with working memory performance (2013)Some individuals report problems during and after Internet sex engagement, such as missing sleep and forgetting appointments, which are associated with negative life consequences. One mechanism potentially leading to these kinds of problems is that sexual arousal during Internet sex might interfere with working memory (WM) capacity, resulting in a neglect of relevant environmental information and therefore disadvantageous decision making. Results revealed worse WM performance in the pornographic picture condition of the 4-back task compared with the three remaining picture conditions. Findings are discussed with respect to Internet addiction because WM interference by addiction-related cues is well known from substance dependencies.
  4. Sexual Picture Processing Interferes with Decision-Making Under Ambiguity (2013) Decision-making performance was worse when sexual pictures were associated with disadvantageous card decks compared to performance when the sexual pictures were linked to the advantageous decks. Subjective sexual arousal moderated the relationship between task condition and decision-making performance. This study emphasized that sexual arousal interfered with decision-making, which may explain why some individuals experience negative consequences in the context of cybersex use.
  5. Cybersex addiction: Experienced sexual arousal when watching pornography and not real-life sexual contacts makes the difference (2013)The results show that indicators of sexual arousal and craving to Internet pornographic cues predicted tendencies towards cybersex addiction in the first study. Moreover, it was shown that problematic cybersex users report greater sexual arousal and craving reactions resulting from pornographic cue presentation. In both studies, the number and the quality with real-life sexual contacts were not associated to cybersex addiction. The results support the gratification hypothesis, which assumes reinforcement, learning mechanisms, and craving to be relevant processes in the development and maintenance of cybersex addiction. Poor or unsatisfying sexual real life contacts cannot sufficiently explain cybersex addiction.
  6. Empirical Evidence and Theoretical Considerations on Factors Contributing to Cybersex Addiction From a Cognitive-Behavioral View (2014) Dysfunctional use of sex mediated the relationship of sexual excitability with cybersex addiction (CA). The results of the study show that there are factors of vulnerability to CA and provide evidence for the role of sexual gratification and dysfunctional coping in the development of cybersex addiction.
  7. Cybersex addiction in heterosexual female users of internet pornography can be explained by gratification hypothesis (2014) Results indicated that Internet porn users rated pornographic pictures as more arousing and reported greater craving due to pornographic picture presentation compared with non-users. Moreover, craving, sexual arousal rating of pictures, sensitivity to sexual excitation, problematic sexual behavior, and severity of psychological symptoms predicted tendencies toward cybersex addiction in porn users. Being in a relationship, number of sexual contacts, satisfaction with sexual contacts, and use of interactive cybersex were not associated with cybersex addiction.
  8. Prefrontal control and internet addiction: a theoretical model and review of neuropsychological and neuroimaging findings (2015)Consistent with this, results from functional neuroimaging and other neuropsychological studies demonstrate that cue-reactivity, craving, and decision making are important concepts for understanding Internet addiction. The findings on reductions in executive control are consistent with other behavioral addictions, such as pathological gambling. They also emphasize the classification of the phenomenon as an addiction, because there are also several similarities with findings in substance dependency.  Moreover, the results of the current study are comparable to findings from substance dependency research and emphasize analogies between cybersex addiction and substance dependencies or other behavioral addictions.
  9. Implicit associations in cybersex addiction: Adaption of an Implicit Association Test with pornographic pictures. (2015) Recent studies show similarities between cybersex addiction and substance dependencies and argue to classify cybersex addiction as a behavioral addiction. In substance dependency, implicit associations are known to play a crucial role. Results show positive relationships between implicit associations of pornographic pictures with positive emotions and tendencies towards cybersex addiction, problematic sexual behavior, sensitivity towards sexual excitation as well as subjective craving.
  10. Symptoms of cybersex addiction can be linked to both approaching and avoiding pornographic stimuli: results from an analog sample of regular cybersex users (2015) Results showed that individuals with tendencies toward cybersex addiction tended to either approach or avoid pornographic stimuli. Additionally, moderated regression analyses revealed that individuals with high sexual excitation and problematic sexual behavior who showed high approach/avoidance tendencies, reported higher symptoms of cybersex addiction. Analogous to substance dependencies, results suggest that both approach and avoidance tendencies might play a role in cybersex addiction.
  11. Getting stuck with pornography? Overuse or neglect of cybersex cues in a multitasking situation is related to symptoms of cybersex addiction (2015)Individuals with tendencies towards cybersex addiction seem to have either an inclination to avoid or to approach the pornographic material, as discussed in motivational models of addiction. The results of the current study point towards a role of executive control functions, i.e. functions mediated by the prefrontal cortex, for the development and maintenance of problematic cybersex use (as suggested by Brand et al., 2014). Particularly a reduced ability to monitor consumption and to switch between pornographic material and other contents in a goal adequate manner may be one mechanism in the development and maintenance of cybersex addiction.
  12. Trading Later Rewards for Current Pleasure: Pornography Consumption and Delay Discounting (2015)Study 1: Participants completed a pornography use questionnaire and a delay discounting task at Time 1 and then again four weeks later. Participants reporting higher initial pornography use demonstrated a higher delay discounting rate at Time 2, controlling for initial delay discounting. Study 2:  Participants who abstained from pornography use demonstrated lower delay discounting than participants who abstained from their favorite food. The finding suggests that Internet pornography is a sexual reward that contributes to delay discounting differently than other natural rewards. It is therefore important to treat pornography as a unique stimulus in reward, impulsivity, and addiction studies and to apply this accordingly in individual as well as relational treatment.
  13. Sexual Excitability and Dysfunctional Coping Determine Cybersex Addiction in Homosexual Males (2015)Recent findings have demonstrated an association between CyberSex Addiction (CA) severity and indicators of sexual excitability, and that coping by sexual behaviors mediated the relationship between sexual excitability and CA symptoms. The aim of this study was to test this mediation in a sample of homosexual males.  Questionnaires assessed symptoms of CA, sensitivity to sexual excitation, pornography use motivation, problematic sexual behavior, psychological symptoms, and sexual behaviors in real life and online. Moreover, participants viewed pornographic videos and indicated their sexual arousal before and after the video presentation. Results showed strong correlations between CA symptoms and indicators of sexual arousal and sexual excitability, coping by sexual behaviors, and psychological symptoms. CA was not associated with offline sexual behaviors and weekly cybersex use time. Coping by sexual behaviors partially mediated the relationship between sexual excitability and CA. The results are comparable with those reported for heterosexual males and females in previous studies and are discussed against the background of theoretical assumptions of CA, which highlight the role of positive and negative reinforcement due to cybersex use.
  14. Subjective Craving for Pornography and Associative Learning Predict Tendencies Towards Cybersex Addiction in a Sample of Regular Cybersex Users (2016)There is no consensus regarding the diagnostic criteria of cybersex addiction. Some approaches postulate similarities to substance dependencies, for which associative learning is a crucial mechanism. In this study, 86 heterosexual males completed a Standard Pavlovian to Instrumental Transfer Task modified with pornographic pictures to investigate associative learning in cybersex addiction. Additionally, subjective craving due to watching pornographic pictures and tendencies towards cybersex addiction were assessed. Results showed an effect of subjective craving on tendencies towards cybersex addiction, moderated by associative learning. Overall, these findings point towards a crucial role of associative learning for the development of cybersex addiction, while providing further empirical evidence for similarities between substance dependencies and cybersex addiction
  15. Exploring the Relationship between Sexual Compulsivity and Attentional Bias to Sex-Related Words in a Cohort of Sexually Active Individuals (2016) – This study replicates the findings of this 2014 Cambridge University study that compared the attentional bias of porn addicts to healthy controls. The new study differs: rather than comparing porn addicts to controls, the new study correlated scores on a sex addiction questionnaire to the results of a task assessing attentional bias (explanation of attentional bias). The study described two key results: 1) Higher sexual compulsivity scores correlated with greater interference (increased distraction) during the attentional bias task. This aligns with substance abuse studies. 2) Among those scoring high on sexual addiction, fewer years of sexual experience were related to greater attentional bias. The authors concluded that this result could indicate that more years of “compulsive sexual activity” lead to greater habituation or a general numbing of the pleasure response (desensitization). An excerpt from the conclusion section: “One possible explanation for these results is that as a sexually compulsive individual engages in more compulsive behaviour, an associated arousal template develops and that over time, more extreme behaviour is required for the same level of arousal to be realised. It is further argued that as an individual engages in more compulsive behaviour, neuropathways become desensitized to more ‘normalised’ sexual stimuli or images and individuals turn to more ‘extreme’ stimuli to realise the arousal desired.”
  16. Mood changes after watching pornography on the Internet are linked to symptoms of Internet-pornography-viewing disorder (2016) – Excerpts: The main results of the study are that tendencies towards Internet Pornography Disorder (IPD) were associated negatively with feeling generally good, awake, and calm as well as positively with perceived stress in daily life and the motivation to use Internet pornography in terms of excitation seeking and emotional avoidance.  Furthermore, tendencies towards IPD were negatively related to mood before and after watching Internet pornography as well as an actual increase of good and calm mood. The relationship between tendencies towards IPD and excitement seeking due to Internet-pornography use was moderated by the evaluation of the experienced orgasm’s satisfaction. Generally, the results of the study are in line with the hypothesis that IPD is linked to the motivation to find sexual gratification and to avoid or to cope with aversive emotions as well as with the assumption that mood changes following pornography consumption are linked to IPD (Cooper et al., 1999 and Laier and Brand, 2014).
  17. Problematic sexual behavior in young adults: Associations across clinical, behavioral, and neurocognitive variables (2016) – Individuals with Problematic Sexual Behaviors (PSB) exhibited several neuro-cognitive deficits. These findings indicate poorer executive functioning (hypofrontality) which is a key brain feature occuring in drug addicts. A few excerpts: From this characterization, it is be possible to trace the problems evident in PSB and additional clinical features, such as emotional dysregulation, to particular cognitive deficits…. If the cognitive problems identified in this analysis are actually the core feature of PSB, this may have notable clinical implications.
  18. Executive Functioning of Sexually Compulsive and Non-Sexually Compulsive Men Before and After Watching an Erotic Video (2017) Exposure to porn affected executive functioning in men with “compulsive sexual behaviors”, but not healthy controls. Poorer executive functioning when exposed to addiction-related cues is a hallmark of substance disorders (indicating both altered prefrontal circuits and sensitization). Excerpts: This finding indicates better cognitive flexibility after sexual stimulation by controls compared with sexually compulsive participants. These data support the idea that sexually compulsive men do not to take advantage of the possible learning effect from experience, which could result in better behavior modification. This also could be understood as a lack of a learning effect by the sexually compulsive group when they were sexually stimulated, similar to what happens in the cycle of sexual addiction, which starts with an increasing amount of sexual cognition, followed by the activation of sexual scripts and then orgasm, very often involving exposure to risky situations.
  19. Exposure to Sexual Stimuli Induces Greater Discounting Leading to Increased Involvement in Cyber Delinquency Among Men (2017) – In two studies exposure to visual sexual stimuli resulted in: 1) greater delayed discounting (inability to delay gratification), 2) greater inclination to engage in cyber-deliquency, 3) greater inclination to purchase counterfeit goods & hack someone’s Facebook account. Taken together this indicates that porn use increases impulsivity and may reduce certain executive functions (self-control, judgment, foreseeing consequences, impulse control). Excerpt: These findings provide insight into a strategy for reducing men’s involvement in cyber delinquency; that is, through less exposure to sexual stimuli and promotion of delayed gratification. The current results suggest that the high availability of sexual stimuli in cyberspace may be more closely associated with men’s cyber-delinquent behavior than previously thought.
  20. Predictors for (Problematic) Use of Internet Sexually Explicit Material: Role of Trait Sexual Motivation and Implicit Approach Tendencies Towards Sexually Explicit Material (2017) – Excerpts: The present study investigated whether trait sexual motivation and implicit approach tendencies towards sexual material are predictors of problematic SEM use and of the daily time spent watching SEM. In a behavioral experiment, we used the Approach-Avoidance Task (AAT) for measuring implicit approach tendencies towards sexual material. A positive correlation between implicit approach tendency towards SEM and the daily time spent on watching SEM might be explained by attentional effects: A high implicit approach tendency can be interpreted as an attentional bias towards SEM. A subject with this attentional bias might be more attracted to sexual cues on the Internet resulting in higher amounts of time spent on SEM sites.
  21. Tendencies toward Internet-pornography-use disorder: Differences in men and women regarding attentional biases to pornographic stimuli (2018) – [greater cue reactivity/sensitization, enhanced cravings]. Excerpts Several authors consider Internet-pornography-use disorder (IPD) as addictive disorder. One of the mechanisms that has been intensively studied in substance- and non-substance-use disorders is an enhanced attentional bias toward addiction-related cues. Attentional biases are described as cognitive processes of individual’s perception affected by the addiction-related cues caused by the conditioned incentive salience of the cue itself. It is assumed in the I-PACE model that in individuals prone to develop IPD symptoms implicit cognitions as well as cue-reactivity and craving arise and increase within the addiction process. To investigate the role of attentional biases in the development of IPD, we investigated a sample of 174 male and female participants. Attentional bias was measured with the Visual Probe Task, in which participants had to react on arrows appearing after pornographic or neutral pictures. In addition, participants had to indicate their sexual arousal induced by pornographic pictures. Furthermore, tendencies toward IPD were measured using the short-Internetsex Addiction Test. The results of this study showed a relationship between attentional bias and symptom severity of IPD partially mediated by indicators for cue-reactivity and craving. While men and women generally differ in reaction times due to pornographic pictures, a moderated regression analysis revealed that attentional biases occur independently of sex in the context of IPD symptoms. The results support theoretical assumptions of the I-PACE model regarding the incentive salience of addiction-related cues and are consistent with studies addressing cue-reactivity and craving in substance-use disorders.