In science-speak, tasty sugary/fatty food and intense sexual stimulation are the two most potent 'natural reinforcers.' That is, these two perfectly natural attractions are likeliest to affect your brain somewhat like drugs (the term 'drug' includes substances like nicotine and alcohol).1 Specifically, they produce neurochemical events in the reward circuitry of the brain that are designed to bend your priorities.
This is what makes them risky – their power to reorder your priorities in ways that do not serve you, and that you would not choose if you were thinking clearly. To give an extreme example, in New York City, HIV cases in gay men under 30 have jumped 33% since 2001.2 The cause is widespread 'barebacking,' that is anal sex without a condom. Could this be occurring because the reward circuitry of these men's brains is valuing some aspect of a condomless experience more highly than their safety and the safety of their future partners? If so, research related to addiction may explain this seemingly irrational result. The brain chemistry that makes addicts focus on their chosen substances or activities, even if their lives fall apart as a result, is also a major factor behind humanity's tendency to get its priorities wrong when confronted with the intense lure of junk food and potent sexual stimuli - especially empty-calorie junk food and affectionless sexual stimuli. It's almost as if there's a 'judgment-bending continuum,' at one end of which are substances and activities that distort judgment so tyrannically that they prove highly addictive (think of heroin and methamphetamine). At the other end there are substances and activities that register as enjoyable, but don't prevent us from steering for our true wellbeing (socializing with friends, a favorite meal). In between are substances and activities that have a wide range of effects on people's judgment. Under their influence, some people become obsessed and behave self-destructively (or destructively toward others). Other people simply make decisions they later regret or develop habits they don't want. Other people suffer attitude changes and mood shifts that alter their perceptions unconsciously - causing them to perceive and value experiences and people differently than they otherwise would. Still other people manage to stay on a reasonably even keel. (Most of us don't react the same way all of the time, of course.) In any case, of the natural, non-drug enticements, junk food and sexual stimulation have the greatest potential to distort judgment and erode self-control. Let's consider why.
Why Junk Food and Sexual Stimulation?
We evolved in ancestral environments poor in both concentrated sugars and erotic movies, ads, and images. Honey was a rare source of concentrated sugar, and cave girls were no doubt cute, but their erotically-posed images weren't airbrushed to perfection and projected all over every cave wall. Nor did ubiquitous ads promise great pharmaceutically- or surgically-enhanced sex for men and women. Although sexual arousal and sugar are natural, our brains don't seem to be all that well adapted to today's abundant levels of these stimulants. Exposure to supranormal, i.e., above normal, stimulation sends especially powerful neurochemical reward signals to the brain. Our subconscious registers that something really, really valuable is before us. In such circumstances, we are designed to override our self-control mechanisms so we don't miss an apparent golden opportunity...for a sugary snack or some quick, hot sex. In effect, exposure to these things produces a 'false positive' message. If we were to steer for our true wellbeing, we'd usually say "maybe just this once," or "think I'll pass." Instead we find ourselves saying "I'd be a fool to pass this up whenever I have the chance!" Unfortunately these 'golden opportunities' sometimes end up to be habit-forming for reasons explained below. They bend our minds by subtly altering our brains in ways we aren't conscious of. This is a hazard of having an out-dated brain in a modern environment. Think of Native Americans and the disastrous consequences of their vulnerability to the strong alcohol to which they had not adapted. Now, obesity in the US has increased to the point where, for the first time, our life span is predicted to be shorter than that of our parents. And knee-jerk pursuit of the erotic leads people to undervalue the other aspects of intimate relationships, to their detriment,3 as they get hooked on 'hotness' (even two-dimensional) above intimacy. How does the brain cause us to give so much attention to these attractions that we lose sight of our true wellbeing?
Reinforcers and Exaggerated Focus
The term 'reinforcer' refers to a substance or behavior that exaggerates our learning about it – and anything associated with it. Recreational drugs are examples of reinforcers. They trigger surges of the neurotransmitter dopamine in the nucleus accumbens (part of the reward circuitry of the brain). Scientists have shown that the natural activities of eating and sexual behavior also trigger surges of a neurochemical known as dopamine. For example, from the moment a rat senses a potential mate behind a screen until the finale of copulation itself, dopamine rises in the nucleus accumbens. A Dutch research scientist remarked that brain scans of men ejaculating resemble those of people shooting heroin. And dopamine has also been found to be linked with obesity.4 This dopamine-reward response makes food and sex 'natural reinforcers,' so it's not surprising that "highly palatable foods and potent sexual stimuli" have an effect on the brain like drugs.5 Also see this article in which Dr. Larry Young says:
Past studies have found the dopamine system of the nucleus accumbens produces the rewarding and sometimes addictive effects of sex, food and drugs of abuse.
A big dopamine surge tells us that the substance or activity we are focused on is either good or else better than expected. This message feeds back to exaggerate our learning about it, to direct our future attention to anything associated with it, and to cue our motor cortex to 'go for it.' Here's one of the most important points for understanding why natural reinforcers are potentially risky. The key element that causes you to find something especially rewarding is not the nutrient, substance, or activity itself, but the dopamine released in your brain. Dopamine surges can be powerful "this is great; pay attention!" messages – and they can occur whether a stimulus is artificial or natural, and even though the stimulus may be perfectly benign in small quantities. Alas, a powerful "Focus on this!" command doesn't necessarily mean that the activity or substance is actually worthy of your exaggerated attention (and your consequent inattention to other things or people in your life). To figure out your ideal priorities, you need the input from the higher centers of your brain. (More on that in a moment.) Incidentally, your mind-bending reward circuitry (seat of the dopamine mechanism) is, in some ways, an unreliable measurer of pleasure. According to the late Swiss neuropsychiatrist Klaus Grawe, your reward circuitry is more sensitive to surprises than to actual levels of pleasure. It readily learns to ignore familiar sources of pleasure in favor of things that initially registered as 'unexpectedly good,' whether or not they still provide pleasure, or have even grown unpleasant. For this reason a daring, spontaneous sexual exploit, such as making love in the office stairwell, will register as more rewarding than an afternoon of nourishing, affectionate lovemaking with a mate. The first was unexpected, even if uncomfortable, while the second, however delicious and truly rewarding, was more predictable. Whatever the true level of pleasure involved, you are programmed to record the first experience as more rewarding, and, all things being equal, to seek similar experiences again. So what then keeps us from behaving like compulsive novelty seekers all of the time? The new brain, or forebrain, inhibits impulsivity by integrating past experience and the wisdom of avoiding risk. Ideally, as we focus on long-term consequences it tempers dopamine activity in the reward circuitry of the brain, allowing us to reframe our impulses more wisely. In the case of supranormal stimulation, however, we produce extra dopamine or otherwise disturb our neurotransmitter ratios. This moves our attention away from the reasons for moderating our behavior, and directs it toward the stimulus. Moreover, our brain won't let us forget about such 'wonderful' events. It produces a substance called glutamate, which rewires memory and learning pathways. Thereafter, we detect cues connected with the stimulant more efficiently than before. Think of an alcoholic having an urge to drink when she walks past a bar and smells beer, or hears the sound of clanking bottles. In short, our exaggerated learning can cause us to place way too much value on certain objectives, reordering our priorities away from our deeper values. This tendency to focus keenly on whatever the brain decides is most rewarding (dopamine-stimulating) has the potential to lead us away from the balancing behaviors that would naturally protect us. Both a rich dessert after a healthy meal or an orgasm after leisurely, affectionate lovemaking are less likely to result in a regrettable behavior pattern than junk food or intense sexual stimulation alone. In other words, the real risk is the logical, but dangerous, focus on the most intensely stimulating aspects of eating or sex. Healthy food and heart-centered lovemaking are protective because they strengthen equilibrium at a neurochemical level, making us less impulsive. The reward circuitry of the brain discounts the true value of these protective factors in its pursuit of stimulation for its own sake. Research is showing that some people are especially vulnerable to the dopamine signals that exaggerate learning. For them some activities or substances more easily become so compelling that they lose sight of their best interests. For example, fewer dopamine receptors (possibly genetic), and childhood stress have both been associated with susceptibility to addiction or alterations to the dopamine system.6 Some characteristics of stimulation are also more likely to strengthen reinforcement – regardless of the individual's innate vulnerability. For example, novelty-on-demand releases lots of dopamine. An example would be slot-machines, with their constant promise of thrilling (high dopamine) anticipation at the pull of a lever (or swipe of a card). Novelty-on-demand is also a big part of the lure of Internet sex websites, with their promise of more lurid images at the click of a mouse. Pursuit of novelty no doubt also exaggerates the appeal of casual sexual encounters. In other words, in these instances, we are exposed to greater risk of having our minds "bent" than we realize. So what does all this mean? In the following article, we'll look at some of the implications of 'natural reinforcement,' and its parallels with drug use - including signs that may indicate our minds are 'bending,' possible effects on our intimate relationships, and suggestions for maintaining equilibrium in the modern world. "Mind-benders: When 'Natural' Is Risky – Part II"
- 1. See remarks of Princeton professor Bart Hoebel.
- 2. See HIV rates rise in gay New Yorkers under 30
- 3. Statistically, a committed relationship is a predictor of longevity and better health.
- 4. See Dopamine found to be linked with obesity and Your Brain on Food: Neuroimaging reveals a shared basis for chocoholia and drug addiction.
- 5. Again, see remarks of Professor Bart Hoebel
- 6. See Obesity linked to fewer 'pleasure' receptors, Low Level of Brain Dopamine D2 Receptors in Methamphetamine Abusers and Dopamine Release in Response to a Psychological Stress in Humans and Its Relationship to Early Life Maternal Care