Certain changes in brain function help distinguish people with sex addiction from others not affected by this condition, according to recent findings from a group of British and American researchers. Like all other forms of behavioral addiction, sex addiction (compulsive sexual behavior, hypersexuality) is distinguished by dysfunctional changes in brain function, as well as by the adoption of daily routines and actions that support these changes. In a study published in 2014 in the journal PLOS One, researchers from four British institutions and one U.S. institution compared the function of several key brain areas in people affected by sex addiction to the function of the same areas in people unaffected by the condition. Sex Addiction A person with sex addiction has problems with sexual fantasy, sexual thinking or real-world sexual behavior that significantly damage his or her ability to lead a stable life centered on a sense of emotional well-being. Specific problems associated with the condition include the recurring use of sex or sexual thought\/fantasy as an \u201cescape\u201d from unpleasant situations or moods, loss of control over sexual behavior or sexual thought\/fantasy, a compelling and recurring need to participate in sexual activities that don\u2019t necessarily bring pleasure, a sex-related inability to meet core responsibilities or obligations and a recurring involvement in dysfunctional sexual activity or sexual thought\/fantasy that damages the ability to form stable personal, social or professional relationships with others. Men and women can develop a sex addiction related to real-world sexual interactions with others, pornography use or other avenues of sexual expression. However, symptoms of the condition can vary considerably between the two genders, and doctors can easily fail to recognize addictive sexual thoughts or behaviors in women. Sex addiction can also appear in people of all sexual orientations. Unfortunately, the condition has no standard reference for diagnosis in the U.S. Doctors rely on a range of screening tools to identify sex addiction in general, a specific addiction to pornography use or a specific addiction to Internet-based pornography use (sometimes known as cybersex addiction). Behavioral Addiction and Brain Function Substance addiction is well-known for its impact on the normal function of a group of brain structures known informally as the pleasure center. In fact, lasting chemical changes in the pleasure center form the basis for the onset of physical dependence and drug\/alcohol addiction. A large body of scientific and clinical evidence strongly indicates that the core functional changes found in the brains of people affected by substance addiction also appear in the brains of people affected by behavioral addictions, a group of conditions that include gambling disorder (the only behavioral addiction with an official definition in the U.S.), Internet addiction and shopping addiction, as well as sex addiction. As in a person with a drug or alcohol addiction, altered brain function in a person with a behavioral addiction generally supports continued, dysfunctional involvement in the activity responsible for the initiation of the addiction process. Which Brain Functions Change? In the study published in PLOS One, researchers from Yale University and British institutions including the University of Cambridge and the British Association for Counselling and Psychotherapy used real-time brain scans of 38 adults to distinguish the brain changes that occur in people with sex addiction. Half of these adults had symptoms that indicated the presence of sex addiction while the other half acted as a generally healthy comparison group unaffected by the condition. The researchers conducted the brain scans while the members of both groups watched a combination of sex-related explicit videos and videos with no overt sexual content. In addition, they asked the participants to describe how much they liked the sexually explicit material, as well as how much desire they felt after viewing the material. After completing the brain scans, the researchers concluded that, compared to their counterparts unaffected by sex addiction, the participants dealing with the condition experienced an unusual elevation of activity in three separate parts of the pleasure center. These brain structures are responsible for things such as the ability to recognize a rewarding sensation and the ability to control emotional responses to pleasure. The researchers also concluded that the observed brain function changes in the study participants with sex addiction made these participants desire sex more but did not make them like sex more than their unaffected counterparts. The study\u2019s authors believe that this unusual juxtaposition between sexual desire and sexual liking largely helps explain the presence of sex addiction.