(CNN) As details about the man suspected of fatally shooting eight people at Atlanta-area spas unfold, the controversial concept of sex addiction has resurfaced.
Local law enforcement told reporters that shooting suspect Robert Aaron Long had "made indicators that he has some issues -- potentially sexual addiction -- and may have frequented some of these places in the past." Law enforcement also shared that Long had recently been kicked out of his family's house because of his sex addiction, which included regularly watching pornography for hours. Former rehabilitation facility roommates of Long's have said sexual addiction was something the suspect was being treated for and was distraught over.
But despite social acceptance of the term -- and the pattern of killers claiming it as a motive for their crimes -- sex addiction isn't an accepted psychiatric diagnosis.
That's because the "gold standard in terms of how we think of addiction" is determined by how substances, behaviors or activities trigger certain brain receptors and responses, said Dr. Ziv Cohen, a forensic and clinical psychiatrist and an adjunct assistant clinical professor of psychiatry at Columbia University. That is neurobiological evidence of addiction, which researchers have observed in people who gamble or consume drugs or alcohol, but largely not in people who have identified as sex or porn addicts.
For this reason, sex addiction has previously been rejected for inclusion in the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, the handbook used by health care professionals as the authoritative guide to diagnosing mental disorders. People are still treated for or seek support for this issue, but experts have said there are other factors to consider.
Symptoms of addictions include "impaired control over behavior, social impairment, ... risky use that is continuing despite clear physical and other risks to the individual, and the development of, in the case of substances, tolerance and withdrawal," said Dr. Paul Appelbaum, the chair of the DSM Steering Committee at the APA and a professor of psychiatry at Columbia University in New York City.
Psychiatrists are also hesitant to characterize levels or brands of sexuality as pathological.
"American psychiatry, for many years, considered homosexuality a psychiatric illness," Cohen said. "There's a legacy from that, a very painful legacy."
Secondly, there are many people "who struggle with healthy sexuality who feel guilty or ashamed of normal sexuality," Cohen added. "There's a concern that if you say that there's something called 'sex addiction,' that a lot of people who really don't have it will start to think that their sexuality, their sexual urges, are not healthy."
Also, knowing "where to draw the line between healthy and unhealthy sexual urges" is difficult, Cohen said. Sexual urges that violate the rights of other people are easy to classify as pathological. "But if you're simply saying you have a high sex drive, which leads you to watch a lot of pornography or to pay for sex, it's harder to just intrinsically label that as pathological because it's not involved in violating the rights of others."
The clinical illegitimacy of sex addiction doesn't mean, however, that people's personal issues with sex aren't real. Brain activity isn't the only way that mental health professionals identify and diagnose disorders. Whether a person's symptoms interfere with the ability to function in various aspects of life is also a consideration.
Advocates of treating sex addiction as a legitimate disorder "would say, 'we have subjective distress and functional impairment in individuals with sex addiction, and therefore it should be a diagnosis,'" Cohen said. "You do have clinicians who are out there treating sex addiction, even though it's not an official diagnosis. So that can seem a little confusing."
Sex Addicts Anonymous is a 12-step recovery program that provides no scientific or clinical expertise, and therefore doesn't get involved in clinical discussions "around whether sex addiction is an addiction or not," said Phillip, the program manager of public information at the International Service Organization of SAA, Inc., in Houston. "I can tell you, however, from our experience, that we can definitely say that for us, sex addiction exists."
What seems like sex addiction could be hypersexuality, which is sometimes a symptom of bipolar disorder or impulse control disorders, Cohen said.
"In bipolar disorder, when you're having a manic episode, you tend to be very hyper, you have a lot of energy, you become very hedonistic, seeking pleasure," he explained. "Manic people often end up becoming very sexually impulsive."
People who feel normal sexual urges but aren't satisfied with sexual activities -- and therefore can't stop -- would be exhibiting compulsive sexual behaviors, which could be in the obsessive-compulsive disorder spectrum, Cohen said.
The most robust predictor for identifying as a sex addict is coming from a conservative, religious background "where very rigid, heteronormative, monogamy-focused rules about sexuality are promoted," said David J. Ley, a clinical psychologist and author of the book "The Myth of Sex Addiction."
"Through the sexual world that we live in, these people ... are not prepared to manage these sexual desires that come up for them and the opportunity to pursue them. And so they hate themselves for having these sexual desires."
Suppressing those desires may make the feelings more powerful and harder to avoid, Ley added, even if they don't rise to the level of a mental disorder.
"People do struggle with these issues," Ley said. "But it's really important for us to understand why they struggle with them, and why certain people struggle with them and others don't, so that we can help these people."