Читать книгу Real Hope, True Freedom - Milton S Magness - Страница 14

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When I (Milton) first attended graduate school in the 1970s, I was taught that the brain was pretty much set at birth. It was believed that people were born with a large but limited number of brain cells and that number decreased through the years. Further, it was thought that neuropathways were already fully developed and would change little throughout life.

However, we now know that, just as with other parts of the body, we produce new brain cells (known as neurogenesis) throughout our lives. An article in the scientific journal Cell gives evidence that 700 new neurons are added to the hippocampus daily corresponding to an annual turnover of 1.75 percent of the neurons in that part of the brain.¹ Neurogenesis is good news in that it helps restore healthy brain function and improve the quality of life for people with a variety of disorders and aids recovery from addiction.

When it comes to understanding addiction and recovery, of even greater importance is neuroplasticity—the brain’s ability to reorganize itself by forming new neural connections throughout life. A research study showed that the hippocampus—the part of the brain that holds spatial representation capacity—of London taxi drivers was significantly larger than that of London bus drivers. Scientists at University College, London conducted Magnetic Resonance Imaging (MRI) scans of sixteen London cabbies and found that the hippocampus was significantly larger than that of the fifty control subjects. They also found that the hippocampus was more developed in cab drivers who had been driving for forty years compared to those who had driven for a shorter period of time.² The scientists theorized that since bus drivers travel the same route every day, they do not exercise that part of the brain as much as taxi drivers who have to navigate different routes constantly.

Psychiatrist Jeffrey Schwartz, regarded as one of the leading experts in the field of neuroplasticity, coined the term “brain lock” to describe both obsessive-compulsive behavior and a treatment plan based in neuroplasticity he developed for obsessive-compulsive disorder (OCD) patients. He said persons with OCD can self-treat their condition using four steps:

1. Relabel the obsessive thoughts and compulsive urges as obsessions and compulsions, not as real thoughts.

2. Reattribute the obsessive thoughts to a brain malfunction called OCD.

3. Refocus on a wholesome, productive activity for at least fifteen minutes.

4. Revalue the entire obsession and compulsion group as having no useful meaning in your life.³

Although sex addiction is not the same as OCD, certainly many of the behaviors in sex addiction and other forms of addiction involve obsessive thinking and compulsive behaviors. As George Koob, director of the National Institute on Alcohol Abuse and Alcoholism in Bethesda, Maryland, put it,

A lot of people think addiction is what happens when someone finds a drug to be the most rewarding thing they’ve ever experienced. But drug abuse is not just feeling good about drugs. Your brain is changed when you misuse drugs. It is changed in ways that perpetuate the problem. The changes associated with drug use affect how addicts respond to drug cues, like the smell of a cigarette or the sight of a shot of vodka. Drug abuse also changes how other rewards, such as money or food, are processed, decreasing their relative value.⁴

Nikolaas Tinbergen, a Nobel Prize-winning ethologist, coined the term “supernormal stimuli.” He found that he could create stimuli that were far stronger than the natural stimuli that cause certain animal behaviors. For example, he constructed plaster eggs and found that birds would choose to sit on eggs that were larger and more vividly colored than their own eggs. Some of the eggs were so large that birds had a hard time remaining on them without sliding off. He also found that certain territorial fish would more vigorously attack wooden fish models that were painted more vividly. In one study he constructed cardboard dummy butterflies with more defined markings and found that males would prefer to try to mate with them than real females.⁵ This may help explain why sex addicts might be more interested in watching pornography than being sexual with a partner in a committed relationship.

Things we see clearly affect our brains. Pornography triggers brain activity in sex addicts that is similar to that triggered by drugs in drug addicts. Cambridge neuroscientist Valerie Voon conducted a study to see what changes take place in the brains of people with and without compulsive sexual behavior.⁶

The study used Functional MRI (fMRI) to assess nineteen subjects with compulsive sexual behavior and nineteen healthy subjects as they viewed sexually explicit videos compared with non-sexually exciting videos. Dr. Voon concluded, “there are clear differences in brain activity between patients who have compulsive sexual behavior and healthy volunteers.”⁷

Sex addicts who are married or are in committed relationships know that viewing pornography negatively affects their desire to be sexual with their partner. Young and otherwise healthy men who suffer from sex addiction may find it difficult to be aroused by their partner. Often, they go to physicians to see if there is a medical problem only to find out that they are in good health and there is no medical reason for them to have erectile difficulties. They may take testosterone and drugs for erectile dysfunction to counter the problem even after determining the problem is not physical. The use of pornography and the fantasies reinforced by masturbating to pornography has altered their brains.

Therapists and physicians, specifically urologists, have long known there is a link between pornography use and brain function. A fascinating aspect of the Voon study is that it provides, for the first time, scientific evidence of a link between pornography use and erectile dysfunction. The researchers found that participants “experienced diminished libido or erectile function specifically in physical relationships with women (although not in relationship to the sexually explicit material).”⁸

Within the sex addiction therapy professional community, there is a lot of discussion about this study. Caution abounds not to make too much of any single study and to understand the limitations of neuroimaging studies. However, evidence continues to mount that the brains of sex addicts are altered by their compulsive sexual activity.

There is increasing evidence that the brain registers all pleasures or rewards in the same way, whether they originate with alcohol or other drugs, food, or sex. In the brain, pleasurable experiences facilitate the release of the neurotransmitter dopamine, which influences the brain’s system of reward-related learning. This system has an important role in sustaining life because it links activities needed for human survival (such as eating and sex) with pleasure and reward. The brain’s reward pathway includes those areas involved with motivation and memory as well as pleasure. As a result, the more pleasurable an experience is, the more powerful the memory of it tends to be, and the more motivated the individual is to repeat it.⁹

In another study, sixty-four men between the ages of twenty-one and forty-five were given brain scans using MRIs. The researchers found that the subjects who watched pornography often had a smaller striatum—an important part of the brain’s reward system involved in sexual arousal. The study’s lead researcher, Simone Kühn, said, “That could mean that regular consumption of pornography more or less wears out your reward system.”¹⁰ He surmised that study subjects who watch a lot of pornography need increasing stimulation to experience the same amount of pleasure or reward.¹¹

Such research disproves the argument of pornography advocates that porn is just an expression of a high sexual desire. Those who use pornography most have less response to sexual images, and therefore, less sexual desire. They consume more and more pornography in order to get a brain-reward response.

As a person’s reward circuitry becomes increasingly dulled and desensitized by drugs, nothing else can compete—food, family, and friends lose their relative value, while the ability to curb the need to seek and use drugs progressively vanishes. Ironically, and perhaps cruelly, eventually even the drug loses its ability to produce pleasure, but the compromised brain leads addicted people to continue to pursue it anyway as the memory of the drug and the pleasure it no longer produces becomes more powerful than the drug itself.¹²

Gradually scientists are gathering evidence that the changes in the brain brought about by drug addiction are also taking place in the brains of sex addicts. While this does not give sex addicts an excuse for their acting out, it does help explain why someone who otherwise makes good decisions will engage in behavior that causes such harm. Why, for example, would a physician engage in unprotected intercourse with a prostitute? Why would a minister who is entrusted with the spiritual guidance of his flock be sexual with parishioners? Why would a successful executive engage in sexual behavior with subordinates that he knows could result in a sexual harassment lawsuit? The only thing that explains such effectively insane behavior is that sex addiction has significantly changed brain functioning—including reasoning and decision-making.

Evidence continues to mount that addiction-based changes in the brain warrant classifying addiction as a brain disease. A recent article in the New England Journal of Medicine concluded that neuroscience continues to support the brain disease model of addiction and that neuroscientific research offers new opportunities for the prevention and treatment of substance addiction and behavioral addiction related to food, sex, and gambling, and may also improve our understanding of the processes involved in voluntary behavioral control.¹³ It notes that “the concept of addiction as a disease of the brain challenges deeply ingrained values about self-determination and personal responsibility that frame drug use as a voluntary, hedonistic act.”¹⁴ While classifying addiction as a brain disease may be understandably upsetting to partners of sex addicts who believe their partners may use the “disease card” as an excuse for their behavior, viewing sex addiction through the lens of a disease model has important implications for the treatment approaches we use.

1 K. L. Spalding, “Dynamics of Hippocampal Neurogenesis in Adult Humans,” Cell 153, no.6 (2013): 1219–1227.

2 F. Jabr, “Cashe Cab: Taxi Drivers’ Brains Grow to Navigate London Streets,” Scientific American, December 8, 2011, http://www.scientificamerican.com/article/london-taxi-memory/.

3 J. M. Schwartz, Brain Lock: Free Yourself from Obsessive-Compulsive Behavior (New York: Regan Books, 1997).

4 B. Brookshire, “Addiction Showcases the Brain’s Flexibility,” Science News: Magazine of the Society for Science & the Public, August 5, 2014, https://www.sciencenews.org/blog/scicurious/addiction-showcases-brain-flexibility.

5 G. Ciotti, “Supernormal Stimuli: This Is Your Brain on Porn, Junk Food, and the Internet,” Huffington Post, July 17, 2014, http://www.huffingtonpost.com/gregory-ciotti/supernormal-stimuli-this-_b_5584972.html?utm_hp_ref=tw.

6 V. Voon, T. B. Mole, P. Banca, et al., “Neural Correlates of Sexual Cue Reactivity in Individuals with and without Compulsive Sexual Behaviours,” PLOS ONE 9, no. 7 (2014), e102419.

7 Ibid.

8 Ibid.

9 Helpguide.org, “Understanding Addiction: How Addiction Hijacks the Brain,” accessed September 20, 2016, http://www.helpguide.org/harvard/how-addiction-hijacks-the-brain.htm.

10 S. A. Kühn, “Brain Structure and Functional Connectivity Associated with Pornography Consumption, the Brain on Porn,” JAMA Psychiatry, 71, no. 7 (2014): 827–834.

11 Ibid.

12 National Institutes of Health, “The Brain: Understanding Neurobiology—The Essence of Drug Addiction,” accessed September 20, 2016, https://science.education.nih.gov/supplements/nih2/addiction/guide/essence.html.

13 N. D. Volkow, “Neurobiologic Advances from the Brain Disease Model of Addiction,” The New England Journal of Medicine 374, no. 4 (2016): 363–371.

14 Ibid.

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