FIRST SOME BACKGROUND
Nicole Prause has an agenda and is not shy about expressing her beliefs that porn addiction doesn't exist and the porn use never causes problems, in anyone, under any circumstances. For a long time her twitter motto was:
"Studying why people choose to engage in sexual behaviors without invoking addiction nonsense."
Prause has teamed up several times with David Ley (author of the Myth of Sex Addiction) to produce papers, blog posts, and presentations saying porn is harmless, never causes sexual problems, as is actually beneficial to users. I wrote this short piece about both, after Ley attacked NoFap on Psychology Today - http://yourbrainonporn.com/david-ley-attacks-nofap
In 2013, Prause published an EEG study that she said dismantled porn and sex addiction. Unfortunately, she misrepresented the actual findings in the media, by saying porn "addicts" brain did not respond like other addicts. This was blatantly false.
MY analysis of it - http://yourbrainonporn.com/sexual-desire-not-hypersexuality-related-neurophysiological-responses-elicited-sexual-images-2013
Commenting under the Psychology Today interview of Prause, senior psychology professor emeritus John A. Johnson said:
"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? I think it could be due to her preconceptions--what she expected to find."
link - http://www.psychologytoday.com/blog/the-sexual-continuum/201307/new-brain-study-questions-existence-sexual-addiction/comments#comment-556448
Here are three peer-reviewed analysis which agree with John A Johnson...that Prause misrepresented her findings (Number 1 is the first Cambridge University study on porn addicts, with 10 neuroscientists)
1) Neural Correlates of Sexual Cue Reactivity in Individuals with and without Compulsive Sexual Behaviours (2014) http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0102419
2) Highdesire, or ?merely? an addiction? A response to Steele et al., by Donald L. Hilton, Jr., MD http://www.socioaffectiveneuroscipsychol.net/index.php/snp/article/view/23833/32589
3) Neuroscience of Internet Pornography Addiction: A Review and Update http://www.mdpi.com/2076-328X/5/3/388
EXCERPT FROM #3:
An EEG study on those complaining of problems regulating their viewing of internet pornography has reported the neural reactivity to sexual stimuli [303]. The study was designed to examine the relationship between ERP amplitudes when viewing emotional and sexual images and questionnaire measures of hypersexuality and sexual desire. The authors concluded that the absence of correlations between scores on hypersexuality questionnaires and mean P300 amplitudes when viewing sexual images ?fail to provide support for models of pathological hypersexuality? [303] (p. 10). However, the lack of correlations may be better explained by arguable flaws in the methodology. For example, this study used a heterogeneous subject pool (males and females, including 7 non-heterosexuals). Cue-reactivity studies comparing the brain response of addicts to healthy controls require homogenous subjects (same sex, similar ages) to have valid results. Specific to porn addiction studies, it?s well established that males and females differ appreciably in brain and autonomic responses to the identical visual sexual stimuli [304,305,306]. Additionally, two of the screening questionnaires have not been validated for addicted IP users, and the subjects were not screened for other manifestations of addiction or mood disorders.
Moreover, the conclusion listed in the abstract, ?Implications for understanding hypersexuality as high desire, rather than disordered, are discussed? [303] (p. 1) seems out of place considering the study?s finding that P300 amplitude was negatively correlated with desire for sex with a partner. As explained in Hilton (2014), this finding ?directly contradicts the interpretation of P300 as high desire? [307]. The Hilton analysis further suggests that the absence of a control group and the inability of EEG technology to discriminate between ?high sexual desire? and ?sexual compulsion? render the Steele et al. findings uninterpretable [307].
Finally, a significant finding of the paper (higher P300 amplitude to sexual images, relative to neutral pictures) is given minimal attention in the discussion section. This is unexpected, as a common finding with substance and internet addicts is an increased P300 amplitude relative to neutral stimuli when exposed to visual cues associated with their addiction [308]. In fact, Voon, et al. [262] devoted a section of their discussion analyzing this prior study?s P300 findings. Voon et al. provided the explanation of importance of P300 not provided in the Steele paper, particularly in regards to established addiction models, concluding,
Thus, both dACC activity in the present CSB study and P300 activity reported in a previous CSB study[303] may reflect similar underlying processes of attentional capture. Similarly, both studies show a correlation between these measures with enhanced desire. Here we suggest that dACC activity correlates with desire, which may reflect an index of craving, but does not correlate with liking suggestive of on an incentive-salience model of addictions. [262] (p. 7)
So while these authors [303] claimed that their study refuted the application of the addiction model to CSB, Voon et al. posited that these authors actually provided evidence supporting said model.
Bottom line: Only 2 brain studies on porn users have **claimed** to be inconsistent with the addiction model. Both are EEG studies by Nicole Prause.
Reality: Both Prause EEG studies align with the addiction model
1) - The 2013 EEG study found sensitization and aligns with the 2 Cambridge studies.
2) - This current EEG study found desensitization and aligns with the Max Plank study on porn users (see below)
Also note: Several other brain studies on porn users have found evidence of addiction, or addiction related brain changes. See - http://www.yourbrainonporn.com/brain-scan-studies-porn-users
THE CURRENT EEG STUDY
See the YBOP critique - http://www.yourbrainonporn.com/modulation-late-positive-potentials-sexual-images-problem-users-and-controls-inconsistent-porn
About this current EEG study. Contrary to Nicole Prause's claim, this new EEG study actually aligns with last years brain scan study on porn users. The Max Planck study and this EEG study found desensitization (or habituation) in heavy porn users:
Brain Structure and Functional Connectivity Associated With Pornography Consumption: The Brain on Porn (2014) http://yourbrainonporn.com/brain-structure-and-functional-connectivity-associated-pornography-consumption-2014
Specifically, the Max Planck study found that more porn use correlated with shrinkage of brain regions associated with sexual reward and motivation. But here's the key - It also found that **more porn use correlated with less brain activation when guys viewed sexual images for a half of a second**. In other words, more porn lead to less sexual excitement in response to rather bland sexual pictures.
The Prause EEG study found the same thing: that "porn addicts" had less brain response to a sexual picture than non addicts. It was a one second exposure to vanilla porn, and obviously boring.
Take way: Both studies found desensitization and the need for greater stimulation in heavy porn users. Not so surprising and indicates tolerance, which is the need for greater stimulation to receive the level of same buzz. Sounds like addiction to me.
And that's what the German scientists believed about their same findings. In this article (http://www.dw.com/en/pea-brain-watching-porn-online-will-wear-out-your-brain-and-make-it-shrivel/a-17681654), head researcher of the German study, Simone K?hn, said:
?That could mean that regular consumption of pornography more or less wears out your reward system.?
A possible explanation is that heavy users eventually need more stimulation to fire up their reward circuitry. Said the study -
?This is in line with the hypothesis that intense exposure to pornographic stimuli results in a downregulation of the natural neural response to sexual stimuli.?
K?hn says existing psychological, scientific literature suggests consumers of porn will seek material with novel and more extreme sex games.
?That would fit perfectly the hypothesis that their reward systems need growing stimulation.?
In her study Nicole Prause actually acknowledges that Kuhn might be right: that still images are not very exciting for porn addicts, and may be more exciting for the controls who didn't watch porn. However, that 2-sentence admission is buried in the discussion.
Pretty simple - In this current EEG study porn addicts were not excited by 1-second exposure to photos of vanilla porn. These are Nicole Prause's actual findings, and align with the 2014 Max Planck study. This study certainly does not "disprove addiction." as it indicates tolerance, and other brain studies have revealed that heavy porn use can lead to addiction-related brain changes.
EXCERPT FROM "Neuroscience of Internet Pornography Addiction: A Review and Update" http://www.mdpi.com/2076-328X/5/3/388
Another EEG study involving three of the same authors was recently published [309]. Unfortunately, this new study suffered from many of the same methodological issues as the prior one [303]. For example, it used a heterogeneous subject pool, the researchers employed screening questionnaires that have not been validated for pathological internet pornography users, and the subjects were not screened for other manifestations of addiction or mood disorders.
In the new study, Prause et al. compared EEG activity of frequent viewers of Internet pornography with that of controls as they viewed both sexual and neutral images [309]. As expected, the LPP amplitude relative to neutral pictures increased for both groups, although the amplitude increase was smaller for the IPA subjects. Expecting a greater amplitude for frequent viewers of Internet pornography, the authors stated, ?This pattern appears different from substance addiction models?.
While greater ERP amplitudes in response to addiction cues relative to neutral pictures is seen in substance addiction studies, the current finding is not unexpected, and aligns with the findings of K?hn and Gallinat [263], who found more use correlated with less brain activation in response to sexual images. In the discussion section, the authors cited K?hn and Gallinat and offered habituation as a valid explanation for the lower LPP pattern. A further explanation offered by K?hn and Gallinat, however, is that intense stimulation may have resulted in neuroplastic changes. Specifically, higher pornography use correlated with lower grey matter volume in the dorsal striatum, a region associated sexual arousal and motivation [265].
It?s important to note that the findings of Prause et al. were in the opposite direction of what they expected [309]. One might expect frequent viewers of Internet pornography and controls to have similar LPP amplitudes in response to brief exposure to sexual images if pathological consumption of Internet pornography had no effect. Instead, the unexpected finding of Prause et al. [309] suggests that frequent viewers of Internet pornography experience habituation to still images. One might logically parallel this to tolerance. In today?s world of high-speed Internet access, it is very likely that frequent consumers of Internet pornography users view sexual films and videos as opposed to still clips. Sexual films produce more physiological and subjective arousal than sexual images [310] and viewing sexual films results in less interest and sexual responsiveness to sexual images [311]. Taken together, the Prause et al., and K?hn and Gallinat studies lead to the reasonable conclusion that frequent viewers of internet pornography require greater visual stimulation to evoke brain responses comparable to healthy controls or moderate porn users.
In addition, the statement of Prause et al. [309] that, ?These are the first functional physiological data of persons reporting VSS regulation problems? is problematic because it overlooks research published earlier [262,263]. Moreover, it is critical to note that one of the major challenges in assessing brain responses to cues in Internet pornography addicts is that viewing sexual stimuli is the addictive behavior. In contrast, cue-reactivity studies on cocaine addicts utilize pictures related to cocaine use (white lines on a mirror), rather than having subjects actually ingest cocaine. Since the viewing of sexual images and videos is the addictive behavior, future brain activation studies on Internet pornography users must take caution in both experimental design and interpretation of results. For example, in contrast to the one-second exposure to still images used by Prause et al. [309], Voon et al. chose explicit 9-second video clips in their cue reactivity paradigm to more closely match Internet porn stimuli [262]. Unlike the one-second exposure to still images (Prause et al. [309]), exposure to 9-second video clips evoked greater brain activation in heavy viewers of internet pornography than did one-second exposure to still images. It is further concerning that the authors referenced the K?hn and Gallinat study, released at the same time as the Voon study [262], yet they did not acknowledge the Voon et al. study anywhere in their paper despite its critical relevance.