Anthony Weiner is again embroiled in a sexting scandal. (Bebeto Matthews/AP)

Dangr33 is back. Yep, it wasn’t enough for disgraced former New York congressman Anthony Weiner to be caught sexting twice or even to bare his soul in a documentary about his sextcapades. Now he’s been caught sexting a woman, again not his wife, with his young son in the crotch shot.

There are many answers to the question of why smart men do really stupid things, but this latest development in Weiner’s weird sex life has people wondering if the man might be mentally ill.

Sexting, like Internet addiction, is not included by the American Psychiatric Association in its Diagnostic and Statistical Manual of Mental Disorders. But in the DSM’s most recent edition, Internet Gaming Disorder is listed as warranting more clinical research. Other countries such as China and South Korea, as well as the World Health Organization, do recognize Internet addiction as a treatable psychological disorder.

On the one hand, sexting between consenting adults is considered by many to be a safe form of sexual expression. On the other hand, when does electronic foreplay become compulsive? And what are we to make of Weiner’s very public indiscretions with sexting, or “pocket porn” as it is sometimes known? (On Monday, his wife, Huma Abedin, a key aide to Hillary Clinton, released a statement saying she was separating from her husband.)

“Addiction is an irrational behavior,” said New York psychologist Kimberly Young, one of the first clinicians to recognize and treat Internet addiction. “And [Weiner] is definitely acting out, especially with a highly visible wife.”

According to the Center for Internet Addiction, which Young founded, sexting is often done by those who suffer from low self-esteem. It’s seen as a problem mostly of adolescents and young people.

“It’s a juvenile behavior: It’s sex, but not really sex,” Young said. “We see it a lot in those with social anxiety. ... [Weiner] doesn’t necessarily fit the typical profile, but sometimes they don't.”

Pocket-porn “addicts” are not defined by the sex act itself or the choice of sexual partner, experts say, but rather by an inability or unwillingness to stop acting out their sexual needs despite the personal costs.

Sexting probably has a biological component, Young said, and although the research is still new, such a finding would not be surprising. Sexual acts, as well as the act of watching pornography, releases one of the brain’s pleasure chemicals, dopamine. This, in turn, activates the nucleus accumbens, a brain structure involved not only in the enjoyment of pleasurable experiences but also in the pursuit of them.

In other words, the brain of someone who sexts keeps returning to the figurative scene of the crime. The more a person does it, the more he or she wants to keep doing it. Several years ago, when Dutch researchers scanned the brains of men having orgasms, the activity in their brains was akin to that of a heroin rush.

Sexting, of course, is legal. But it is uncomfortably close to other risky obsessions.

“It’s safe and it can be done at home,” Young said. “It fits a lot of addiction models.”

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