Sexual addiction is off the list of mental disorders, and cheating spouses may have to start taking responsibility for their indiscretions.

The American Psychiatric Association omitted addiction to sex from the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), Medical News Today reported.

A study observed 52 people who reported having problems regulating their use of sexual imagery. The research team showed them various colored pictures falling into four categories: pleasant sexual, pleasant non-sexual, neutral, and unpleasant.

Researchers monitored brain wave data during the test to determine event-related responses using electroencephalography (EEG).

A brainwave pattern called the "P300" (which takes place about 300 milliseconds after a person sees a stimulus) was used to calculate the amount of desire after a participant viewed an image.

The researchers believed the individuals suffering from sex addiction would have a high P300 response after viewing suggestive images, but this wasn't the case. The scans showed no spike in the brain wave pattern.

"The brain's response to sexual pictures was not predicted by any of the three questionnaire measures of hypersexuality," Nicole Prouse, senior author of the study, said. "Brain response was only related to the measure of sexual desire. In other words, hypersexuality does not appear to explain brain responses to sexual images any more than just having a high libido."

A 2012 study had the opposite results, pegging sexual addiction as a "legitimate mental disorder."

In the study researchers from UCLA tested the legitimacy of "hypersexual disorder."

In order to be labeled as a health disorder, hypersexuality had to meet a set of criteria.

"As with many other mental health disorders, there must also be evidence of personal distress caused by the sexual behaviors that interfere with relationships, work or other important aspects of life," Rory Reid, who led the study, said.

The researchers conducted psychological testing on 207 study participants, all of which had some type of substance abuse problem or issue with sexual behavior. Eighty-Eight percent of the subjects were classified as "hypersexual."

Examinations found the hypersexual participants were able to be distinguished from those who were not, using the "mental disorder" guidelines.

 "The results lead us to believe that the proposed criteria tend not to identify patients who don't have problems with their sexual behavior. This is a significant finding, since many had expressed concerns that the proposal would falsely classify individuals," Reid said.

"So an individual meeting the criteria for hypersexual disorder can experience significant challenges and consequences in their life. Our study showed increased hypersexual behavior was related to greater emotional disturbance, impulsivity and an inability to manage stress," he said.

Reid believes the P300 response is not enough to take sexual addiction off the "mental disorder" list, Time reported.

 "We can't really assert that," he said. Reid believes the lack of one type of response doesn't mean other signs of addiction that were not measured by the study should be discredited.

He also calls into question the severity of the study participant's addiction and the strength of the images used to elicit the response.

"For the patient who comes in after his third job loss because he can't stop masturbating to porn at work, he doesn't care what we call it: he just wants to know how to change and function more adaptively," Reid said.