by Неизвестный
All addiction involves long-term, sometimes lifelong, neuroplastic change in the brain. For addicts, moderation is impossible, and they must avoid the substance or activity completely if they are to avoid addictive behaviors. Alcoholics Anonymous insists that there are no “former alcoholics” and makes people who haven’t had a drink for decades introduce themselves at a meeting by saying, “My name is John, and I am an alcoholic.” In terms of plasticity, they are often correct.
In order to determine how addictive a street drug is, researchers at the National Institutes of Health (NIH) in Maryland train a rat to press a bar until it gets a shot of the drug. The harder the animal is willing to work to press the bar, the more addictive the drug. Cocaine, almost all other illegal drugs, and even nondrug addictions such as running make the pleasure-giving neurotransmitter dopamine more active19 in the brain. Dopamine is called the reward transmitter, because when we accomplish something—run a race and win—our brain triggers its release. Though exhausted, we get a surge of energy, exciting pleasure, and confidence and even raise our hands and run a victory lap. The losers, on the other hand, who get no such dopamine surge, immediately run out of energy, collapse at the finish line, and feel awful about themselves. By hijacking our dopamine system, addictive substances give us pleasure without our having to work for it.
Dopamine, as we saw in Merzenich’s work, is also involved in plastic change. The same surge of dopamine that thrills us also consolidates the neuronal connections responsible for the behaviors that led us to accomplish our goal. When Merzenich used an electrode to stimulate an animal’s dopamine reward system while playing a sound, dopamine release stimulated plastic change,20 enlarging the representation for the sound in the animal’s auditory map. An important link with porn is that dopamine is also released in sexual excitement,21 increasing the sex drive in both sexes, facilitating orgasm, and activating the brain’s pleasure centers. Hence the addictive power of pornography.
Eric Nestler, at the University of Texas, has shown how addictions cause permanent changes in the brains of animals. A single dose of many addictive drugs will produce a protein, called iFosB (pronounced “delta Fos B”), that accumulates in the neurons. Each time the drug is used, more iFosB accumulates, until it throws a genetic switch, affecting which genes are turned on or off. Flipping this switch causes changes that persist long after the drug is stopped, leading to irreversible damage to the brain’s dopamine system and rendering the animal far more prone to addiction. Nondrug addictions, such as running and sucrose drinking, also lead to the accumulation of iFosB and the same permanent changes in the dopamine system.22
Pornographers promise healthy pleasure and relief from sexual tension, but what they often deliver is an addiction, tolerance, and an eventual decrease in pleasure. Paradoxically, the male patients I worked with often craved pornography but didn’t like it.
The usual view is that an addict goes back for more of his fix because he likes the pleasure it gives and doesn’t like the pain of withdrawal. But addicts take drugs when there is no prospect of pleasure, when they know they have an insufficient dose to make them high, and will crave more even before they begin to withdraw. Wanting and liking are two different things.
An addict experiences cravings because his plastic brain has become sensitizedsup23 to the drug or the experience. Sensitization is different from tolerance. As tolerance develops, the addict needs more and more of a substance or porn to get a pleasant effect; as sensitization develops, he needs less and less of the substance to crave it intensely. So sensitization leads to increased wanting, though not necessarily liking.24 It is the accumulation of iFosB, caused by exposure to an addictive substance or activity, that leads to sensitization.
Pornography is more exciting than satisfying because we have two separate pleasure systems in our brains,25 one that has to do with exciting pleasure and one with satisfying pleasure. The exciting system relates to the “appetitive” pleasure that we get imagining something we desire, such as sex or a good meal. Its neurochemistry is largely dopamine-related, and it raises our tension level.
The second pleasure system has to do with the satisfaction, or consummatory pleasure,26 that attends actually having sex or having that meal, a calming, fulfilling pleasure. Its neurochemistry is based on the release of endorphins, which are related to opiates and give a peaceful, euphoric bliss.
Pornography, by offering an endless harem of sexual objects, hyperactivates the appetitive system. Porn viewers develop new maps in their brains, based on the photos and videos they see. Because it is a use-it-or-lose-it brain, when we develop a map area, we long to keep it activated. Just as our muscles become impatient for exercise if we’ve been sitting all day, so too do our senses hunger to be stimulated.
The men at their computers looking at porn were uncannily like the rats in the cages of the NIH, pressing the bar to get a shot of dopamine or its equivalent. Though they didn’t know it, they had been seduced into pornographic training sessions that met all the conditions required for plastic change of brain maps. Since neurons that fire together wire together, these men got massive amounts of practice wiring these images into the pleasure centers of the brain, with the rapt attention necessary for plastic change. They imagined these images when away from their computers, or while having sex with their girlfriends, reinforcing them. Each time they felt sexual excitement and had an orgasm when they masturbated, a “spritz of dopamine,” the reward neurotransmitter, consolidated the connections made in the brain during the sessions. Not only did the reward facilitate the behavior; it provoked none of the embarrassment they felt purchasing Playboy at a store. Here was a behavior with no “punishment,” only reward.
The content of what they found exciting changed as the Web sites introduced themes and scripts that altered their brains without their awareness. Because plasticity is competitive, the brain maps for new, exciting images increased at the expense of what had previously attracted them—the reason, I believe, they began to find their girlfriends less of a turn- on.
The story of Sean Thomas,27 first published in England’s Spectator, is a remarkable account of a man descending into a porn addiction, and it sheds light on how porn changes brain maps and alters sexual taste, as well as the role of criticalperiod plasticity in the process. Thomas wrote, “I never used to like pornography, not really. Yes, in my teens in the Seventies I used to have the odd copy of Playboy under my pillow. But on the whole I didn’t really go for skin mags or blue movies. I found them tedious, repetitive, absurd, and very embarrassing to buy.” He was repelled by the bleakness of the porn scene and the garishness of the mustachioed studs who inhabited it. But in 2001, shortly after he first went online, he got curious about the porn everyone said was taking over the Internet. Many of the sites were free— teasers, or “gateway sites,” to get people into the harder stuff. There were galleries of naked girls, of common types of sexual fantasies and attractions, designed to press a button in the brain of the surfer, even one he didn’t know he had. There were pictures of lesbians in a Jacuzzi, cartoon porn, women on the toilet smoking, coeds, group sex, and men ejaculating over submissive Asian women. Most of the pictures told a story.
Thomas found a few images and scripts that appealed to him, and they “dragged me back for more the next day. And the next. And the next.” Soon he found that whenever he had a spare minute, he would “start hungrily checking out Net Porn.”
Then one day he came across a site that featured spanking images. To his surprise, he got intensely excited. Thomas soon found all sorts of related sites, such as “Bernie’s Spanking Pages” and the “Spanking College.”
“This was the moment,” he writes, “that the real addiction set in. My interest in spanking got me speculating: What other kinks was I harboring? What other secret and rewarding corners lurked in my sexuality that I would now be able to investigate in the privacy of my home? Plenty, as it turned out. I discovered a serious penchant for, inter alia, lesbian gyne
cology, interracial hardcore, and images of Japanese girls taking off their hotpants. I was also into netball players with no knickers, drunk Russian girls exposing themselves, and convoluted scenarios where submissive Danish actresses were intimately shaved by their dominant female partners in the shower. The Net had, in other words, revealed to me that I had an unquantifiable variety of sexual fantasies and quirks and that the process of satisfying these desires online only led to more interest.”
Until he happened upon the spanking pictures, which presumably tapped into some childhood experience or fantasy about being punished, the images he saw interested him but didn’t compel him. Other people’s sexual fantasies bore us. Thomas’s experience was similar to that of my patients: Without being fully aware of what they were looking for, they scanned hundreds of images and scenarios until they hit upon an image or sexual script that touched some buried theme that really excited them.
Once Thomas found that image, he changed. That spanking image had his focused attention, the condition for plastic change. And unlike a real woman, these porn images were available all day, every day on the computer.
Now Thomas was hooked. He tried to control himself but was spending at least five hours a day on his laptop. He surfed secretly, sleeping only three hours a night. His girlfriend, aware of his exhaustion, wondered if he was seeing someone else. He became so sleep deprived that his health suffered, and he got a series of infections that landed him in a hospital emergency room and finally caused him to take stock. He began inquiring among his male friends and found that many of them were also hooked.
Clearly there was something about Thomas’s sexuality, outside his awareness, that had suddenly surfaced. Does the net simply reveal quirks and kinks, or does it also help create them? I think it creates new fantasies out of aspects of sexuality that have been outside the surfer’s conscious awareness, bringing these elements together to form new networks. It is not likely that thousands of men have witnessed, or even imagined, submissive Danish actresses intimately shaved by their dominant female partners in the shower. Freud discovered that such fantasies take hold of the mind because of the individual components in them. For instance, some heterosexual men are interested in porn scenarios where older, dominant women initiate younger women into lesbian sex. This may be because boys in early childhood often feel dominated by their mothers, who are the “boss,” and dress, undress, and wash them. In early childhood some boys may pass through a period when they strongly identify with their mothers and feel “like a girl,” and their later interest in lesbian sex can express their residual unconscious female identification.28 Hardcore porn unmasks some of the early neural networks that formed in the critical periods of sexual development and brings all these early, forgotten, or repressed elements together to form a new network, in which all the features are wired together. Porn sites generate catalogs of common kinks and mix them together in images. Sooner or later the surfer finds a killer combination that presses a number of his sexual buttons at once. Then he reinforces the network by viewing the images repeatedly, masturbating, releasing dopamine and strengthening these networks. He has created a kind of “neosexuality,” a rebuilt libido that has strong roots in his buried sexual tendencies. Because he often develops tolerance, the pleasure of sexual discharge must be supplemented with the pleasure of an aggressive release, and sexual and aggressive images are increasingly mingled—hence the increase in sadomasochistic themes in hardcore porn.
Critical periods lay the groundwork for our types, but falling in love in adolescence or later provides an opportunity for a second round of massive plastic change. Stendhal, the nineteenth-century novelist and essayist, understood that love could lead to radical changes in attraction. Romantic love triggers such powerful emotion that we can reconfigure what we find attractive, even overcoming “objective” beauty. In On Love Stendhal describes a young man, Alberic, who meets a woman more beautiful than his mistress. Yet Alberic is far more drawn to his mistress than to this woman because his mistress promises him so much more happiness. Stendhal calls this “Beauty Dethroned by Love.” Love has such power to change attraction that Alberic is turned on by a minor defect on his mistress’s face, her pockmark. It excites him because “he has experienced so many emotions in the presence of that pockmark, emotions for the most part exquisite and of the most absorbing interest, that whatever his emotions may have been, they are renewed with incredible vividness at the sight of this sign, even observed on the face of another woman . . . in this case ugliness becomes beauty.”29
This transformation of taste can happen because we do not fall in love with looks alone. Under normal circumstances finding another person attractive can prompt a readiness to fall in love, but that person’s character and a host of other attributes, including his ability to make us feel good about ourselves, crystallize the process of falling in love. Then being in love triggers an emotional state so pleasurable that it can make even pockmarks attractive, plastically rewiring our aesthetic sense. Here is how I believe it works.
In 1950 “pleasure centers” were discovered30 in the limbic system, a part of the brain heavily involved in processing emotion. In Dr. Robert Heath’s experiments on humans— an electrode was implanted into the septal region of the limbic system and turned on— these patients experienced a euphoria so powerful that when the researchers tried to end the experiment, one patient pleaded with them not to. The septal region also fired when pleasant subjects were discussed with the patients and during orgasm. These pleasure centers were found to be part of the brain’s reward system, the mesolimbic dopamine system. In 1954 James Olds and Peter Milner showed that when they inserted electrodes into an animal’s pleasure center while teaching it a task, it learned more easily because learning felt so pleasurable and was rewarded.
When the pleasure centers are turned on, everything we experience gives us pleasure. A drug like cocaine acts on us by lowering the threshold at which our pleasure centers will fire, making it easier for them to turn on. It is not simply the cocaine that gives us pleasure. It is the fact that our pleasure centers now fire so easily that makes whatever we experience feel great.31 It is not just cocaine that can lower the threshold at which our pleasure centers fire. When people with bipolar disorder (formerly called manic depression) begin to move toward their manic highs, their pleasure centers begin firing more easily. And falling in love also lowers the threshold at which the pleasure centers will fire.32
When a person gets high on cocaine, becomes manic, or falls in love, he enters an enthusiastic state and is optimistic about everything, because all three conditions lower the firing threshold for the appetitive pleasure system, the dopamine- based system associated with the pleasure of anticipating something we desire. The addict, the manic, and the lover are increasingly filled with hopeful anticipation and are sensitive to anything that might give pleasure— flowers and fresh air inspire them, and a slight but thoughtful gesture makes them delight in all mankind. I call this process “globalization.”33
Globalization is intense when falling in love and is, I believe, one of the main reasons that romantic love is such a powerful catalyst for plastic change. Because the pleasure centers are firing so freely, the enamored person falls in love not only with the beloved but with the world and romanticizes his view of it. Because our brains are experiencing a surge of dopamine, which consolidates plastic change, any pleasurable experiences and associations we have in the initial state of love are thus wired into our brains.
Globalization not only allows us to take more pleasure in the world, it also makes it harder for us to experience pain and displeasure or aversion. Heath showed that when our pleasure centers fire,34 it is more difficult for the nearby pain and aversion centers to fire too. Things that normally bother us don’t. We love being in love not only because it makes it easy for us to be happy but also because it makes it harder for us to be unhappy.
Globalization also creates an opportunity for us to develop new tastes
in what we find attractive, like the pockmark that gave Alberic such pleasure. Neurons that fire together wire together, and feeling pleasure in the presence of this normally unappealing pockmark causes it to get wired into the brain as a source of delight. A similar mechanism occurs when a “reformed” cocaine addict passes the seedy alleyway where he first took the drug and is overwhelmed with cravings so powerful that he goes back to it. The pleasure he felt during the high was so intense that it caused him to experience the ugly alleyway as enticing, by association.
There is thus a literal chemistry of love, and the stages of romance reflect the changes in our brain during not only the ecstasies but also love’s throes. Freud, one of the first people to describe the psychic effects of cocaine and, as a young man, the first to discover its medical uses, got a glimpse of this chemistry. Writing to his fiancée, Martha, on February 2, 1886, he described taking cocaine while composing the letter. Because cocaine acts on the system so quickly, the letter, as it unfolds, gives us a marvelous window into its effects. He first describes how it makes him talkative and confessional. His initial self- deprecatory remarks vanish as the letter goes on, and soon he feels fearless, identifiying with his brave ancestors defending the Temple in Jerusalem. He likens cocaine’s ability to cure his fatigue to the magical cure he gets from being with Martha romantically. In another letter he writes that cocaine reduces his shyness and depression, makes him euphoric, enhances his energy, self- esteem, and enthusiasm, and has an aphrodisiac effect. He is describing a state akin to “romantic intoxication,”35 when people feel the initial high, talk all night, and have increased energy, libido, self- esteem, and enthusiasm, but because they think everything is good, they may also have impaired judgment— all of which occurs with a dopamine- promoting drug like cocaine. Recent fMRI (functional magnetic resonance imaging) scans of lovers36 looking at photos of their sweethearts show that a part of the brain with great concentrations of dopamine is activated; their brains looked like those of people on cocaine.