Excerpt from an article on Gary Wilson’s site, http://www.yourbrainonporn.com. Great read:
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 (no studies falsify the porn addiction model). The results of these 31 neurological studies (and upcoming studies) are consistent with 200+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 10 recent neuroscience-based reviews of the literature:
- Neuroscience of Internet Pornography Addiction: A Review and Update (2015). A thorough review of the neuroscience literature related to Internet addiction subtypes, with special focus on internet porn addiction. The review also critiques two recent headline-grabbing EEG studies which purport to have “debunked” porn addiction.
- Sex Addiction as a Disease: Evidence for Assessment, Diagnosis, and Response to Critics (2015), which provides a chart that takes on specific criticisms of porn/sex addiction, offering citations that counter them.
- 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.”
- 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”
- 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.“
- 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.”
- 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.”
- 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.”
- 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 7 US Navy doctors and Gary Wilson, 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. A second 2016 paper by Gary Wilson discusses the importance of studying the effects of porn by having subjects abstain from porn use: Eliminate Chronic Internet Pornography Use to Reveal Its Effects (2016).
- 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.
- 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):
- 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.
- 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 pattern in porn addicts (CSB subjects) as seen in drug addicts and alcoholics. 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, yet could achieve erections with porn.
- 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].“
- Novelty, Conditioning and Attentional Bias to Sexual Rewards (2015) – Another Cambridge University fMRI study. 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.
- 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. What’s new is that the findings perfectly matched the prefrontal cortex activation patterns observed in drug addicts: Greater cue-reactivity to sexual images, yet inhibited response to other normal stimuli.
- 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 down-regulating sexual desire. How so? The study reported higher EEG readings (relative to neutral pictures) 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) the study had no control group for comparison; 2) subjects were heterogeneous (males, females, non-heterosexuals); 3) subjects were not screened for mental disorders or addictions; 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. Also see the extensive YBOP critique.
- Modulation of Late Positive Potentials by Sexual Images in Problem Users and Controls Inconsistent with “Porn Addiction” (2015) – Another SPAN Lab EEG (brain-wave) study comparing the 2013 subjects from the above study 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 lead author, Nicole Prause, claims these results “debunk 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 (habituated or desensitized). See this extensive YBOP critique. Five peer-reviewed papers agree that this study actually found desensitization/habituation in frequent porn users: 1, 2, 3, 4. 5.
- HPA Axis Dysregulation in Men With Hypersexual Disorder (2015) – 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 the findings with substance addictions.
- 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?
- Can Pornography be Addictive? An fMRI Study of Men Seeking Treatment for Problematic Pornography Use (2016) – (in the press) 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.
- 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.“
- 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. Main Findings: The neural correlates of appetitive conditioning and neural connectivity were altered in the CSB group. According to the researchers, the first alteration – heightened amygdala activation – might reflect facilitated conditioning (greater “wiring” to previously neutral cues predicting porn images). The second alteration – decreased connectivity between the ventral striatum and the prefrontal cortex – could be a marker for impaired ability to control impulses. Said the researchers, “These [alterations] are in line with other studies investigating the neural correlates of addiction disorders and impulse control deficits.” The findings of greater amygdalar activation to cues (sensitization) and decreased connectivity between the reward center and the prefrontal cortex (hypofrontality) are two of the major brain changes seen in substance addiction. In addition, 3 of the 20 compulsive porn users suffered from “orgasmic-erection disorder”.
- 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).
- 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.
The above studies are all the “brain studies” published (or in the press) on internet porn users.
Together these brain studies found:
- The 3 major addiction-related brain changes: sensitization, desensitization, and hypofrontality.
- More porn use correlated with less grey matter in the reward circuit (dorsal striatum).
- More porn use correlated with less reward circuit activation when briefly viewing sexual images.
- More porn use correlated with disrupted neural connections between the reward circuit and prefrontal cortex.
- Addicts had greater prefrontal activity to sexual cues, but less brain activity to normal stimuli (matches drug addiction).
- 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.
- Enhanced attentional bias comparable to drug users. Indicates sensitization (a product of DeltaFosb).
- Greater wanting & craving for porn, but not greater liking. This aligns with the accepted model of addiction – incentive sensitization.
- Porn addicts have greater preference for sexual novelty yet their brains habituated faster to sexual images. Not pre-existing.
- The younger the porn users the greater the cue-induced reactivity in the reward center.
- Higher EEG (P300) readings when porn users were exposed to porn cues (which occurs in other addictions).
- Less desire for sex with a person correlating with greater cue-reactivity to porn images.
- More porn use correlated with lower LPP amplitude when briefly viewing sexual photos: indicates habituation or desensitization.
- Dysfunctional HPA axis and altered brain stress circuits, which occurs in drug addictions (and greater amygdala volume, which is associated with chronic social stress).
article source: http://www.yourbrainonporn.com/brain-scan-studies-porn-users