Anatomy & physiology teacher Gary Wilson explains the physiology of erections, how overstimulation via today's Internet porn can create erectile dysfunction (even in young men), and how others have recovered. For more information see Is my erectile dysfunction (ED) related to my porn use?
DeltaFosB & sensitization articles
Adolescent brain vulnerabilities
Internet porn is different
Several studies have found relationships between porn use in young men and ED, anorgamsia, low sexual desire, delayed ejaculation and lower brain activation to sexual images.
1) "Neural Correlates of Sexual Cue Reactivity in Individuals with and without Compulsive Sexual Behaviours (2014)" - This fMRI study by Cambridge University found sensitization in porn addicts which mirrored sensitization in drug addicts. It also found that porn addicts fit the accepted addiction model of wanting "it" more, but not liking "it" more. The researchers also reported that 60% of subjects (average age: 25) had difficulty achieving erections/arousal with real partners, yet could achieve erections with porn. From the study:
"CSB subjects reported that as a result of excessive use of sexually explicit materials..... experienced diminished libido or erectile function specifically in physical relationships with women (although not in relationship to the sexually explicit material)"
"Compared to healthy volunteers, CSB subjects had greater subjective sexual desire or wanting to explicit cues and had greater liking scores to erotic cues, thus demonstrating a dissociation between wanting and liking. CSB subjects also had greater impairments of sexual arousal and erectile difficulties in intimate relationships but not with sexually explicit materials highlighting that the enhanced desire scores were specific to the explicit cues and not generalized heightened sexual desire."
A Max Planck study which found 3 significant addiction-related brain changes correlating with the amount of porn consumed. It also found that the more porn consumed correlated with less reward circuit activity in response to brief exposure (.530 second) to vanilla porn. Again, lead author Simone Kühn remarked on the uncharacteristic sluggish response to sexual stimuli seen in heavy porn users-
"That could mean that regular consumption of pornography more or less wears out your reward system."
Simone Kühn continued:
"We assume that subjects with a high porn consumption need increasing stimulation to receive the same amount of reward. That would fit perfectly the hypothesis that their reward systems need growing stimulation."
3) "Modulation of Late Positive Potentials by Sexual Images in Problem Users and Controls Inconsistent with "Porn Addiction" (2015)" - An EEG study comparing the subjects from an earlier study by the same research lab to an actual control group. The results: Compared to controls, porn addicts had less response to one-second exposure to photos of vanilla porn. The lead author, Nicole Prause, claims these results debunk porn addiction. However, these findings align perfectly with Kühn & Gallinat (2014), which found that more porn use correlated with less brain activation in response to pictures of vanilla porn. In other words, "porn addicts" appear to be desensitized and to need greater stimulation than non-addicts to become aroused. Three peer-reviewed papers agree with this analysis of the study.
4) "Adolescents and web porn: a new era of sexuality (2015)" - An Italian study analyzed the effects of Internet porn on high school students, co-authored by urology professor Carlo Foresta, president of the Italian Society of Reproductive Pathophysiology. The most interesting finding is that 16% of those who consume porn more than once a week report abnormally low sexual desire compared with 0% in non-consumers (and 6% for those who consume less than once a week).
5) "Patient Characteristics by Type of Hypersexuality Referral: A Quantitative Chart Review of 115 Consecutive Male Cases (2015)" - Study on men (average age 41.5) with hypersexuality disorders, such as paraphilias and chronic masturbation or adultery. 27 were classified as "avoidant masturbators," meaning they masturbated (typically with porn use) one or more hours per day or more than 7 hours per week. 71% reported sexual functioning problems, with 33% reporting delayed ejaculation. What sexual dysfunction do 38% of the remaining men have? The study doesn't say, and the authors have publicly dismissed requests for ED rates. The two other primary choices for male 'sexual dysfunction' are ED and low libido.
6) Erectile Dysfunction, Boredom, and Hypersexuality among Coupled Men from Two European Countries (2015) - Survey reported a strong correlation between erectile dysfunction and measures of hypersexuality. The study omitted correlation data between erectile functioning and pornography use.
7) Altered Appetitive Conditioning and Neural Connectivity in Subjects With Compulsive Sexual Behavior (2016) - "Compulsive Sexual Behaviors" (CSB) means the men were porn addicts, because CSB subjects averaged nearly 20 hours of porn use per week. The controls averaged 29 minutes per week. Interestingly, 3 of the 20 CSB subjects suffered from "orgasmic-erection disorder," while none of the control subjects reported sexual problems.
8) (not peer-reviewed) Here's a popular article about an extensive analysis of comments and questions posted on MedHelp concerning erectile dysfunction. What's shocking is that 58% of the men asking for help were 24 or younger. Many suspected that internet porn could be involved in their dysfunction, as described in the results from the study -
EXCERPT: The most common phrase is “erectile dysfunction” – which is mentioned more than three times as often as any other phrase – followed by “internet porn,” “performance anxiety,” and “watching porn.” Clearly, porn is a frequently discussed subject: “I have been viewing internet pornography frequently (4 to 5 times a week) for the past 6 years,” one man writes. “I am in my mid-20s and have had a problem getting and maintaining an erection with sexual partners since my late teens when I first started looking at internet porn.”
9) Sexual Desire, not Hypersexuality, is Related to Neurophysiological Responses Elicited by Sexual Images (2013) - This EEG study was touted in the media as evidence against the existence of porn addiction. Not so. In line with the Cambridge studies, this EEG study reported greater cue-reactivity to porn correlated with less desire for partnered sex. Neither finding matched the headlines. Three peer-reviewed papers expose the truth: 1, 2, 3. Read much more.