Pleasure, Pain, Brave New World, and the Brain

Pleasure, Pain, Brave New World, and the Brain

Pleasure. Pain. They sound like opposites, yet they’re not. Sometimes the line is blurred- sometimes it’s nonexistent. And everybody experiences these states differently.  I hate running, but lots of my friends experience runner’s high. I love the burn of spicy food, but many people I know hate it. There are people who cut themselves and enjoy the sensations. Skinny dipping in the winter. Marilyn Manson’s music. Examples are everywhere.

I’d figured that everyone had a different line separating their perceptions of pleasure and pain. But then I came across a review article from the April 2008 issue of Nature, “A Common Neurobiology for Pain and Pleasure,” and learned that the reality is more complex, and more fascinating.

Your brain often receives signals of both pleasure (a subjective emotional reward) and pain (punishment) at the same time, and must decide which to concentrate on and which to ignore. Pleasure becomes keener when it becomes more useful in restoring your body’s balance. Its “reward value” increases. The hungrier we are, the better food tastes. And if you’re in real danger, pain’s unpleasantness, or “punishment value,” increases too. Your brain must weigh the various inputs it receives to decide what to perceive.

“The subjective utility- or ‘meaning’- or pain or pleasure for the individual is determined by sensory, homeostatic, cultural, and other factors that, when combined, bias the… experience of pleasure,”¹ states the article. Essentially, the way we experience a particular sensation depends on its context. Of course our sensory experience is important- something feels good to our body, or it doesn’t.  If chocolate is sweet, you will feel pleasure eating it.

“Homeostatic” refers to the body’s internal drive for balance. If you’re really hungry and have low blood sugar, that piece of chocolate will taste better to you than it would after a big satisfying meal.

It’s like in The Sims. When your character’s basic needs are met, the mood diamond hovering above her head glows a balmy green. This is homoeostasis. But if one or more of her needs is out of whack- say, she needs to go to the bathroom and her house is a mess- the crystal shades toward red. You can restore the happy green color by having her correct these problems. Sometimes, her “bladder” meter is a little high (she sort of has to go) but her house is a rat-infested hole. At that time, getting her to go to the bathroom will barely change her mood crystal’s color, but if she takes out the trash, the color will improve by so much more.

Cultural factors? Say your religion equates the eating of chocolate with damnation. Say you’re not a rebellious sort, you’re hungry and have low blood sugar, and you’re stuck on a deserted island where the only edible substance is chocolate. Is the chocolate going to taste good to you when you finally cave? Will you enjoy it? Will chocolate bring you the pleasure it will bring to someone else, if you know that hellfire awaits you? Not so much. That’s a pretty extreme example, but you get the idea.

According to the Fields Motivation-Decision Model of Pain, if your life is in danger, your brain will automatically downplay pain perception and concentrate on what’s more important for survival. If you’re sitting by the campfire nursing menstrual cramps and a grizzly happens along, you won’t be debilitated by pain- you will get up and run like hell.

This works via the descending pain modulatory system. In the brainstem, a circuit of cells moderates responses to pleasure and pain. Opiates, whether they’re made in your body or administered through drugs, act on this system to produce pain relief.

This descending system is subject to environmental influences, as well. According to this review article, “when subjects who were not expecting an injection of pain-relieving morphine received a hidden injection, its analgesic effects were significantly reduced.”¹ If you don’t think your pain will be relieved, it won’t. At least, not as effectively.

But that doesn’t mean just wishing for pain relief is going to bring it. Some people are unable to banish their pain at all. Sadly, this actually reduces their capacity to experience pleasure, leading to a vicious cycle. Fibromyalgia (generalized pain) and depression frequently occur together in patients, because the sustained pain they are in causes the pleasure rewards they do experience to be less potent.¹ If you’re in constant pain, and this inhibits you from fully enjoying pleasure rewards, both the pain and the depression will get worse together.

The reason for this is the reduced functionality of the phasic dopamine system, one of two neurotransmitter systems that work together to mediate pleasure and pain. The other is the µ-opoid system. With regard to pleasure, dopamine is what makes you want it, and µ-opoids are what make you like it when you get it. The µ-opoids also reduce the perceived unpleasantness of painful stimuli, e.g. bitter foods.

Three regions of the brain act as sites for the interaction between pain and pleasure signals: the nucleus accumbens (NAc), the pallidum, and the amygdala. In general, all three of them release µ-opoids when humans experience painful stimuli. Though their functions differ, these three structures have an interesting feature in common: each has two subregions that interpret pleasure and pain, very close together. This suggests the closeness of these two psychological states, and how interchangeable they can be, with just the right signals from the descending pathway of the brain.

Brave New World: When a culture of pleasure meets a religion of pain

[Spoiler alert! If you haven’t read Aldous Huxley’s Brave New World, go read it. Whether you end up reading the rest of this entry or not, read Brave New World. DO IT. ]

Think about the character of John Savage. John grew up on a reservation isolated from the distant-future world of technology, drugs and constant titillation. Many of the principles and practices of the new world ran contrary to the values he’d learned in his own culture, which stressed the virtues of self-denial and self-mortification. In the end, he was so disgusted with this world that he sought to escape the pollution of civilization. His masochistic orgy of atonement brought him pleasure, but then it turned into his succumbing to what he saw as sin with Lenina Crowne. When he woke up and remembered, he hanged himself.

This example, like my fictitious one about chocolate being against someone’s religion, is extreme. But it’s not entirely foreign to us, is it? When we, as cultural heirs of the Puritans, read this book, we don’t think John Savage is totally crazy. We understand the impulse toward self-denial, the idea of pleasure being unclean somehow. When I read the book, I reacted to the descriptions of the new world with a combination of fascination, longing, and disgust.

Some of this disgust was directed toward myself, for thinking that a world which negates pain and emotion and individuality can have any merits. I was repulsed by the idea that such a world could hold any intrigue for me, when it was devoid of all that leads to depth and meaning.

When John came on the scene, I could understand his internal conflict, his anguish. When he punished himself, I thought his reactions were a bit excessive, yet I understood. I thought of his suicide as a message that a society of pleasure and a culture of pain are irreconcilable.

“Even suffering can be rewarding if it has meaning to the sufferer.” ¹ Prior to his introduction to the New World, John Savage had experienced most of the pleasure rewards of his life as a result of what New World citizens would have called self-inflicted suffering. But his ritual self-mortification formed a large part of the basis for his self-worth. He was fascinated by the technology of the New World, curious about its capacity to provide unadulterated, instant pleasure. But when he experienced it, he felt dirty.  He sought the pleasure he was used to: the cleansing feeling of self-flagellation, hard work and sacrifice. He equated this drive with a sound mind.

Sound familiar? Thought so.

What does this mean for us? We who live by the Protestant work ethic, in a changing world which people often say is headed in a more hedonistic direction- how do we handle it? How important are cultural influences in determining how we interpret pleasure and pain? Would we be able to adapt to a Brave New World, or would the conflict between our sensory experience and cultural values send us into John Savage’s private hell?

Just something to think about.  

Sources:

1) Leknes, Siri, and Irene Tracy. “A common neurobiology for pain and pleasure.” Nature April 2008: 314-320. Electronic.

                2) Huxley, Aldous. Brave New World. New York: Harper& Brothers, 1932. Paperback.