Amid calls for his resignation, New York Rep. Anthony Weiner's political problems grow. And so do questions about the powerful Democratic congressman's risky sexting habit: Is it wayward frat boy behavior or a sign of deeper problems?
At a Monday news conference, Weiner, 46, cried and confessed to having online affairs with six women in the past three years, apologizing to his wife, Huma Abedin, 34, who is Hillary Clinton's closest aide.
Abedin has stood by him so far, telling friends that she and her husband love each other and she is committed to staying in the marriage. She said she knew about the virtual affairs before their marriage, but Weiner promised they had ended.
Abedin, who is traveling with Secretary of State Clinton in the Middle East, was devastated to learn the truth just this week.
Psychologists say she should be. When impulsive habits such as sexting, masturbating and viewing online pornography are repetitive, they can signal deeper problems.
Dr. Martin Kafka, a clinical associate professor of psychiatry at Harvard Medical School, an affiliate of McLean Hospital, said adults who have impulse control problems with sex often have "psychiatric vulnerabilities."
"Most guys don't do these things," he said. "We might think to do them, but we don't. The question is, why do some people have control over their impulses compared to others?"
Weiner's sexting had become a problem for him months before he was caught -- literally -- with his pants down.
Three months ago, the Twitter group #born-freecrew warned young female followers of Weiner about his salacious messages, according to a report today in The New York Times.
The group leader sent the crotch shot that Weiner sent to 21-year-old Washington State college student Gennette Cordova to conservative blogger Andrew Breitbart, who made it public.
But as early as May, the group predicted he would be caught in a sex scandal. In at least two instances, according to the Times, Weiner dropped online contact with the women after they had been identified by #born-freecrew, suggesting he knew he was at risk.
Risky behavior goes hand in hand with the inability to control ones impulses, behavior that can be problematic enough to be called a psychological disorder, say experts.
Impulse control is a part of the larger biological and behavioral system known as self-regulation, according to Lawrence Aber, distinguished professor of applied psychology and public health policy at New York University.
"Our food intake and control over our sexual impulses are all part of it," he said. "It's plan-ful behavior and begins early in life and there are many parts of the brain implicated."
Impulse control or self-regulation is centered in the prefrontal cortex or the thinking part of the brain, which controls intentional behavior.
Impulse control is "self-reinforcing," Aber said. Those who learn to practice it when they are younger get better at it as adults. But, as the recent sex scandals illustrate, adult behavior can be "virtuous or vicious."
"If I could answer the question why some adults are like that and others aren't, the world would be a better place and I would be richer," Aber said.
By age 5, a child should be able to delay gratification for a larger reward, rather than expect immediate gratification for a small reward, Aber said.
Children vary quite a bit and much depends on the "quality of parenting," he said. But socializing techniques such as teaching them to think "cool-ly and abstractly" can also help reign in impulses.
But, in adolescence, a whole new set of impulses kick in, "from sex to drugs to rock and roll," Aber said. "There are a number of underlying biological changes with hormones and marketing consumption."
Now, with the advent of brain imaging, scientists know that the prefrontal cortex does not fully form until a person is in his or her mid-20s.
"The insurance actuarials learned that first," he said. "You have to be 25 to rent a car. It turns out, that's about the average age that structural part of the brain matures."
An adult is often fine for 20 or 30 years and then develops one of the degenerative conditions of aging and can lose self-regulation. Certain forms of drug use -- Parkinson's disease medications, for example -- can trigger gambling addictions. Brain lesions can also affect impulses.
Psychiatrist Kafka, who has not treated Weiner, said that those who exhibit repetitive impulse control problems -- "guys who look at porn, masturbate a lot and expose themselves" -- rather than a single incident, often have an underlying psychiatric disorder.
When these men eventually get to a psychiatrist, they are diagnosed with mood disorders, attention-deficit disorder (ADD) or have abused drugs or alcohol.
"Some people have low-grade depression," he said. "Others have spectrum bipolar disorder with brief hypomanic periods that last a day or two. During that time, they get revved up or impulsive and have a propensity for sex or spending money or not making good decisions."
Those with ADD can have "boredom intolerance," which is associated with risky behavior.
Weiner was adamant that he hasn't had a physical relationship outside of his marriage and some of his constituents have said they are less concerned about his sexting habits than his lies about them.
But Kafka said compulsive sex habits cannot be explained as just rogue behavior that somehow extends late into adulthood.
"I am sure someone may differ with me," Kafka said. "But I don't think it's just a personality thing. I always see it as pathology. ... Usually, it's a mistreated psychiatric disorder, not a character disorder."