Pulling Away (After Sex) by Marnia Robinson D opamine. It's at the core of our sexual drives and survival needs, and it motivates us to do just about everything. This mechanism within the reward center of the primitive brain has been around for millions of years and has not changed. Rats, humans — indeed, all mammals — are very similar in this respect. Dopamine is behind a lot of the desire we associate with eating and sexual intercourse. Similarly, all addictive drugs trigger dopamine (the "craving neurochemical") to stimulate the pleasure/reward center. So do gambling, shopping, overeating and other, seemingly unrelated, activities. Go shopping: dopamine. Smoke a cigarette: dopamine. Computer games: dopamine. Heroin: dopamine. Orgasm: dopamine. They all work somewhat differently on the brain, but all raise your dopamine. You get a bigger blast of dopamine eating high-calorie, high-fat foods than eating low-calorie vegetables. You may believe that you love ice cream, but you really love your blast of dopamine. You're genetically programmed to seek out high-calorie foods over others. Similarly, dopamine drives you to have sex over most other activities. With dopamine as the driving force, biology has designed you to engage in fertilization behavior to make more babies, and urges you to move on to new partners to create greater genetic variety among your offspring. Your primitive brain accomplishes these goals of more progeny and promiscuity by manipulating your brain chemistry, and thus your desires and thoughts. High levels of dopamine increase sexual desire, encouraging you to behave recklessly. The thrill of a new affair and the rush from using pornography are examples of high dopamine. Unfortunately, consistently high levels of dopamine lead to erratic behavior and compulsions that are not conducive to survival. (See the "EXCESS" column in the chart below.) Most mammals, therefore, evolved with defined estrus periods when they "go into heat." The rest of the time they are more or less neutral about sex. Humans, however, don't have a period of "heat" followed by a long period of indifference to sex. Unlike all other mammals, we have the potential for on-going, dopamine-driven sexual desire. Yet we, too, self-regulate. An "off switch" kicks in after too much passion. Two events happen simultaneously. Dopamine plummets and prolactin soars. Dopamine is "go get it!" and prolactin is "whoa!" This mechanism shifts your attention elsewhere: to hunting and gathering, taking care of babies, building shelters, and so forth. Without this natural, protective shutdown, you would pursue sex to the exclusion of all other activities. When rats were wired so that they could push a lever in their cages to stimulate the nerve cells on which dopamine acts, they just kept hitting the lever until they dropped — not even pausing to eat or investigate potential mates. Dopamine is highly addictive; the rise in prolactin puts the brakes on. This event (drop in dopamine and rise in prolactin) is the cause of the emotional separation that so often follows in the days or weeks after a passionate encounter.

FEELINGS & BEHAVIORS ASSOCIATED WITH VARIOUS DOPAMINE LEVELS

EXCESS DEFICIENT "NORMAL" Anxiety Anhedonia - No Pleasure, World Looks Colorless Motivated Psychosis Inability To "Love" Feelings Of Well-Being, Satisfaction Aggression No Remorse About Personal Behavior Pleasure, Reward In Accomplishing Tasks Schizophrenia Depression Healthy Libido Addictions, Compulsions Addictions (seeking relief from depression) Good Feelings Toward Others Paraphilias (Sexual Fetishes) Antisocial behavior Healthy bonding Sexual Addiction Low Libido Maternal/Paternal Love Unhealthy Risk-Taking Erectile dysfunction Healthy risk taking Gambling Lack Of Ambition And Drive Sound choices Impulsive Sensation-Seeking ADD? Realistic expectations Compulsive Activities Social anxiety disorder As you can see from this chart, a balanced level of dopamine is necessary for good mental health. When dopamine drops, you feel like something is dreadfully wrong. Too much dopamine also leads to reckless behavior and restless anxiety, which can be quite severe. These uncomfortable feelings are then projected onto your partner. Bingo! Suddenly, he or she doesn't look so appealing. This is a very uncomfortable cycle to experience in your intimate relationship. During the "hangover," or "low-dopamine" portion of the cycle, you may feel abandoned, or as if someone is demanding things from you in ways that you cannot tolerate. Or you may desperately seek new highs (alcohol, sweets, new partners, pornography, and so forth) to raise your dopamine levels again. Perhaps you can see how this cycle of highs and lows, or attraction and repulsion, can make your relationship feel more like a roller-coaster ride than a romantic fairytale. It is like starting and stopping in heavy traffic. It shows up in lovers' lives as intense attraction, followed by behaviors that tend to separate them. (Prolactin can promote separation, too, as we'll see in a moment.) The point is that conventional sex can play havoc with your neurochemistry. Much of the time, your dopamine levels will be uncomfortably high or uncomfortably low. This is why the ancient Taoists and other sages throughout history have recommended making love without conventional orgasm. By avoiding the extreme highs that over-stimulate the nerve cells in the primitive brain, you also avoid the temporary lows that accompany recovery. You keep your dopamine levels within ideal ranges. This produces a sense of wellbeing, which promotes harmony in your relationship.

Dopamine is not the only culprit that contributes to the behaviors and mood swings that separate intimate partners emotionally. Prolactin, the neurochemical that shoots up after orgasm, is associated with many of the very symptoms that long-term couples complain of in their relationships. (See chart below.) Prolactin's effects can linger. For example, cocaine blasts the brain with high levels of dopamine, and prolactin rises during withdrawal. Indeed, addicts going through withdrawal required two weeks for their prolactin levels to drop to normal. After mating, female rats show surges in prolactin for up to two weeks — even if they don't get pregnant. Finally, prolactin is associated with the stress of feeling hopeless. As partners grow distressed and discouraged by the puzzling highs and lows in their relationships, their higher prolactin levels can compound their distress. They forget what it feels like to be in balance, and gradually lose their natural sense of wellbeing. Both low dopamine and high prolactin make your world look bleak — and increase your craving for better sex or new partners who would raise your dopamine levels (and set you on another addictive cycle of highs and lows). Together these neurochemicals probably account for the "end of the honeymoon," which nearly all couples experience within a year of marriage.

SYMPTOMS ASSOCIATED WITH EXCESS PROLACTIN

WOMEN MEN Loss of libido Loss of libido Mood changes / depression Mood changes/depression Hostility, anxiety Impotence Headache Headache Menopausal symptoms,

even when estrogen is sufficient Infertility Signs of increased testosterone levels Decreased testosterone levels Weight gain Weight gain Intercourse may become painful because of vaginal dryness Peripheral vision problems Infertility, irregular menstruation Gynecomastia (growing breasts) Peripheral vision problems