Is sex as addictive as cocaine or alcohol?

It depends on who you ask. Obviously there is an entire industry built up around the idea that it is, just like there is an industry build around homeopathy and curing gay people, but that doesn't mean the NIH should be funding those things.

A new study sets out to puncture the notion that sex addiction is an actual physical addiction rather than a new label created in an era when psychologists and psychiatrists had set out to over-pathologize everything (which may be coming to a close - the NIH said they are not going to use DSM 5 for anything more than light reading, so there is no longer an incentive to create new diseases which will be valid on insurance claims) - of course the study examining the reality of sex addiction uses another questionable method; hooking people up to a machine and measuring a response and comparing it to survey results.

Dr. Brian Mustanski interviewed the senior author of a new study of sex addiction at Psychology Today:
We found that the brain’s response to sexual pictures was not predicted by any of three different questionnaire measures of hypersexuality. Brain response was only predicted by a measure of sexual desire. In other words, hypersexuality does not appear to explain brain differences in sexual response any more than just having a high libido.
What should make people happy: Dr. Nicole Prause wrote, "If our study is replicated, these findings would represent a major challenge to existing theories of sex addiction" - those first five words tell us we are dealing with someone serious. 

Are examinations of the brain, in this case EEGs because they wanted to see when something is happening rather than where, valid? Typically, imaging studies suffer from being underpowered and the analysis team uses methods that don't control the level of false positives very well. When results look plausible, mistakes are not caught (see a nice overview by author and neuroscientist Daniel Bor) because the researchers have both 'skewed incentives' (1) and no standard ways to measure what brain responses mean. In the case of the study Prause did, they were matching a baseline physical response to answers to survey questions.

They might be fighting an uphill battle examining the existence of sexual addiction. Obviously mainstream media rewards flashy papers - science journalists love to print stories where specific areas of the brain are linked to specific behavior - and that is an incentive for researchers too. For example, if someone creates a study linking fMRI and surveys to liberals being smarter than conservatives, how many publications will rush to print that?  Well, that has happened, so we know just about all of them - and even better if there is mumbo-jumbo about epigenetics in there. (2) It may also be that science journalists have become so consumed with 'science acceptance' that they don't want to look like they are skeptical of anything and are afraid to ask the awkward questions of scientists that they should be asking.

Luckily, fellow neuroscientists are not afraid to ask those awkward questions - they are the ones highlighting the big concerns of imaging studies. They just get a tiny fraction of the coverage that the imaging claims themselves get.

Do Mustanki and Prause have it in for sex addiction? Perhaps. When psychologists put psychological concepts in quotes, they are often meant to be scare quotes, the same way most people intend them that way, so even using the term sex "addiction" means they are not buying it, but a little skepticism is needed in social science so that's fine.  We just have to try and calibrate it. If a skeptical researcher were to discuss Mustanski's bio and write Mustanski's research focuses on understanding the "development" of sexual orientation (my quotation marks) it would be done to make the audience know that they do not believe sexual orientation develops, so quotes can often be a caution for the reader about the intention of the writer.
What does this mean for those in treatment for sex addiction now?

Nothing. The study needs to be replicated. Alternative explanations need to be explored. If the wrong model is currently being used to provide treatments, we must find the right model to help people struggling with their sexual behaviors. We’re working on it!
That has to warm your heart about the future of the field. No self-help book in the works, no 'only center in the world to offer X Brand Name Treatment for Disease Y' stuff.  Let's reproduce it and if it holds up, go after the proper issue rather than making all behavior exculpatory - the way 'I have a disease' claims and analogies are used now to make suspect behavior a little more acceptable. In The Onion's hilarious form:

 I'm Like A Chocoholic, But For Booze



Do some people have self-destructive behavior about sex? Well, sure, just like some people are 'addicted' to watching "TMZ" every day at 5 PM or finding the Holy Grail too. (3) That doesn't make them their own clinical issues, it is just symptomatic of something else. Psychiatry will join the 21st century and leave symptom-based diagnosis behind, like the rest of medicine has.  And some critical self-awareness in the field is a good start.

Study: Vaughn R. Steele, PhD, Cameron Staley, PhD, Timothy Fong, MD and Nicole Prause, PhD, 'Sexual desire, not hypersexuality, is related to neurophysiological responses elicited by sexual images', Socioaffective Neuroscience&Psychology 2013, 3: 20770 - DOI: 10.3402/snp.v3i0.20770

Article/Interview: New Brain Study Questions Existence of “Sexual Addiction" by Dr. Brian Mustanski, Psychology Today

NOTE:

(1) Obviously that is not limited to brain studies.

(2)  But a paper claiming that conservatives were smarter would be examined more critically and Knight Science Journalism Tracker would be scouring the Internet for evidence of an agenda by the researchers.   It isn't just psychology that engages in confirmation bias.

(3) Me, and then the father of Indiana Jones for that second part.