Pleasure has long been dismissed as a morally inferior emotion, the undisciplined indulgence of the glutton, the hedonist or the sexually depraved. But we now know that pleasure as a sensation is neither optional nor whimsical. We’re hardwired to crave it, and we need it for our very survival. Deprived of pleasurable touch, babies wither, and often die. Adults who fail to experience pleasure become anxious, depressed, possibly violent.

Gene Wallenstein, Ph.D., has made his life’s work the examination of where we
fi nd pleasure, how it impacts the brain, and what happens when we’re deprived. An internationally recognized neuroscientist and expert on the biology of emotions, Wallenstein has authored more than 80 scholarly articles, abstracts and book chapters. His books – Mind, Stress and Emotions: The New Science of Mood (Commonwealth Press, 2002), and The Pleasure Instinct: Why We Crave Adventure, Chocolate, Pheromones, and Music (Wiley, 2008) – delve deep into the realms of pleasure, mood and our common human experience. Here, Wallenstein talks with Nexus publisher Ravi Dykema about our inexorable pursuit of pleasure, and what it means to our lives.

RD: How did you get involved in the study of pleasure and mood?

GW: I’ve always been interested in understanding how biology impacts feelings, moods and certain behaviors. As a neuroscientist, I was saddened that there wasn’t more understanding of how the brain supports emotions. Emotions were seen as the purview of psychologists and maybe even philosophers. What scientifi c studies there were, were
almost always about fear or startle response, because it’s easy to study in animals. But I was always interested in the fl ip side, the pleasurable emotions.

I remember once when I was really young, I was skiing down a slope toward the end of the day. There weren’t a lot of other people around, and the sun was starting to get low, but it was still warm. I felt so great, fl ying down the hill on skis; it was really a peak experience, pure pleasure.

There are so many different examples of that kind of peak experience, of pure pleasure. What struck me was that those peak-pleasure experiences vary greatly depending on a person’s life circumstances. But there are certain specific kinds of stimulation that seem
to reliably elicit pleasure. Everyone has experienced pleasure in slightly different ways, but you can come up with a list of things that always make people feel pleasure. So I began to wonder, is there anything about pleasure that’s culturally independent or invariant across people? Would the same kinds of things elicit pleasure in a person from New Guinea as in us?

RD: Such as?

GW: Look at the way babies prefer certain kinds of stimuli very early in life, independent of culture. In the visual domain, they love lateral symmetry (when the left side mirrors the right side) and enhanced contrast. In the auditory domain, they love inflection and timing,
sort of the music of language. And if you watch a mother or father interacting with their baby, it’s practically identical from culture to culture. They use the same set of acoustic rhythms, dramatic pitch contour changes, exaggerated facial expressions and so forth. We seem to have a core set of innate preferences, and even responses, in all the senses.

RD: In terms of that core set of preferences, was there anything that you found surprising or especially intriguing?

GW: Yes, people have a key, core set of preferences that seems to be very robust, and it exists in every sensory domain. What intrigued me was that during a child’s development these preferences seem to happen in a sequence; they don’t emerge in a haphazard way.

As children develop, their lower-level functional systems tend to develop first. So in the visual system, those systems that track movement and motion emerge earlier than those that are supporting color vision or binocularity. As a result, you’ll see certain preferences
emerge in children at the same time when those preferences are needed to support the development of that function.

RD: So in the early developmental stages, we’re attracted to the very things we need most, which supports their further development. Does that continue into adulthood? Are you and I attracted to the things we need to help us be healthy and maximize our effectiveness?

GW: Yes and no. There is some evidence to show that some of these preferences carry on into early adulthood. The maturation of the visual and other systems continues into our 20s and 30s, and some of our early preferences in those areas die hard. For example, that innate love for the singsong, rhythmic sound of language that is responsible in childhood for helping us learn language, is most likely as important in adulthood as
a basis for music appreciation.

Then there’s a dark side to our innate attraction to those things we need to develop our nervous systems. We’re not living in the hunter-gatherer era any longer; we’re in a radically different environment, in which our instinctive attractions may actually be detrimental to us. For example, we have an innate desire for sweet tastes. As primates, we were fruitavores for a long time. The desire for sweetness prompted us to seek sugarcontaining foods, like fruit, as a quick energy source to power cells. The sweet taste was important to survival.

Fast-forward to our current day and age. We no longer have to climb trees or search high and low for a little fruit; sugar sources are abundant and cheap. And we now have an unparalleled rise in obesity, diabetes and other diseases. So we still have that innate preference for sweetness, but it’s now threatening our survival, rather than promoting it.

There are many other examples of how the pleasure instinct impacts us in a negative way, especially in terms of addiction. For example, some people are addicted to sex. That same pleasure instinct that prompted procreation and thus the survival of our species may now, in some circumstances, be detrimental.

RD: What other innate preferences persist for us in adulthood?

GW: One that comes to mind is lateral symmetry: if we draw a line down the center of any object, and that object looks identical on both sides, that’s a strong lateral symmetry. If it looks different on one side versus the other, then it’s a weaker lateral symmetry. Infants who are just minutes old, who have never even seen objects before, have a
profound preference for objects with strong lateral symmetry.

If you show an infant a drawing of a face with the features arranged in a very symmetrical fashion versus another drawing with the same features, but sort of scattered, so they’re not symmetrical, the babies don’t even look at the non-symmetrical object. They prefer the face with symmetry. And they have had no experience looking at a face before. This has been replicated with all sorts of objects, in addition to faces.

We know this preference for lateral symmetry is important for maturing neurological systems. We also know that lateral symmetry preferences apply to the body as well as the face, and that people tend to prefer mates with strong lateral symmetry. This has been replicated in at least a hundred studies in various populations around the world.

Interestingly, a lateral symmetry of body – the right and left sides being the same – tends to correlate with predictors of biological fitness. In most species that have been studied, when embryological development is challenged (through such things as chromosomal issues, recessive genes or environmental stressors during gestation), the mature organisms tend to have pronounced lateral asymmetry; they tend to be less symmetrical. So it could be that the innate preference for lateral symmetry, when applied to selection of a mate, is geared toward finding someone who has the fittest genes. That person would also be the most physically attractive to us.

RD: Dr. Wallenstein, this brings up acocktail-party topic. Why are men in the modern developed world so attracted to thin women when our not-so-distant ancestors preferred women with curves?

GW: I think it depends where you look. In the United States and maybe North America and Western Europe, thinner women are considered more attractive. But I wonder if that’s true in most modern cultures? In Samoan cultures, Polynesian cultures, maybe even South America, more robust women are more appreciated.

There do seem to be some invariants across cultures that have nothing to do with overall fatness or thinness: waist-to-hip ratio. The ideal ratio is something along the lines of 0.7. In many studies, when asked “Who do you find most attractive?” and “Who would you most like to marry and have children with?” men almost always chose the pictures of women who have a waist-to-hip ratio of around 0.7 (for example, 42” hips, 29.4” waist).

Now, this waist-to-hip ratio is completely independent of weight or overall size; it’s the ratio itself that’s important. For example, Audrey Hepburn and Marilyn Monroe had it; these were two incredibly different looking women, with different looking bodies.

RD: But the pleasure instinct, as you said earlier, can get us in trouble. Neurologically, our frontal cortex provides the brakes to our actions. We feel an impulse to do something that brings us pleasure, but we’re not powerless; if we want to, we can apply the brakes and stop that impulse. But some people don’t seem to be able to halt impulses as well as others. Teenagers, for example, are at a stage where they’re especially incapable of stopping some of those impulses. How do you account for that in an evolutionary sense, or in terms of brain development?

GW: Well, we know that the frontal cortex of the brain, and the medial frontal cortex in particular, is not fully developed until very late in adolescence. As you said, this area is thought to provide inhibitory control – one reason why teenagers seem to lack impulse control. They simply have a different set of neurological circuits than do adults. And
teenagers don’t so much have a lack of control as a desire to experience pleasure to the extreme, whether it’s skiing or drinking or sex.

I think a strong understanding of basic biological development and the pleasure instinct can help govern our school policies, our laws and our expectations for normal everyday behavior.

Now, when you consider addiction in the context of the pleasure instinct, it’s not a surprise that there are addicted people. Sometimes you’ll hear statements like “Well, addicts just happen to have a particularly susceptible genetic disposition to addiction.” But in this framework we’ve been discussing, one could say we all have that susceptibility. Frankly, it’s surprising that more people aren’t addicts.

RD: In your book, you discuss a condition that results from babies not being touched. It has lots of profound implications. Can you explain it to our readers?

GW: Infants and small children who are deprived of regular touch are susceptible to a condition called marasmus; they become extremely emaciated, and literally waste away. In fact, in studies of babies in orphanages in the early 1900s, called “foundling homes,” the mortality rates from marasmus were shockingly high, approaching 100 percent. Small children who don’t get a lot of tactile stimulation in the form of touching, holding, rocking
and so forth, but do get enough to survive, may have delayed development across every sensory domain.

We’ve known for some time that children who aren’t touched have delayed physical development, like walking, crawling and sitting up. But it also appears that they have delays in learning, language development, cognitive development and many other areas. And this is true of all mammals, not just humans or even just primates.

Tactile stimulation is crucial for normal brain development. The neural systems that support the perception of touch develop before any others. Other sensory domains seem to be developmentally dependent on the normal development of touch; even social functioning is impacted. It seems that touch is as essential to surviving and thriving
as oxygen.

RD: Then could you make the generalization that a society or era that is more accepting of touching is happier and healthier, and that a society or era that prohibits touch might produce less healthy people?

GW: I think you can. The need for touch certainly doesn’t stop in infancy. It’s important
for normal brain development and growth throughout the life span. When I was in grad school, we thought the brain developed for the first 20 years or so of life. We now know there’s consistent growth of new neurons throughout life. So it would seem that regular touch would be essential for normal, healthy brain function throughout life. It would
also seem that civilizations, populations and groups of people who have dramatically
repressed touch would suffer in some ways in terms of both psychological and physical health.

RD: So in adulthood, if we thwart our needs – for touch, for social interaction, for sex, for our many other needs – can it cause disruptions in our lives?

GW: I think it can. One would expect – and there’s evidence in the literature to support this – that when you have repression of a basic need, it tends to be compensated for in other ways.

RD: I’m thinking specifically of the recent scandal of Catholic priests preying on young boys. A lot of people would make an association between their celibacy and their destructive behaviors. You can also see it in people who obsessively and repeatedly diet, and then binge on food. Has this been studied?

GW: Yes. There are many examples in the literature, for example, linking drug use to the stimulation of a particular system that failed to adequately develop. We no longer think addiction is uniform. Some addictive agents trigger different pleasure centers than others. So, for example, amphetamines and cocaine target very different parts of the brain
than opium and morphine. They stimulate different sets of brain circuits, and elicit very different feelings.

So if you’re using cocaine, your resulting behaviors will be more activated and energized, which could be compensating for the repression of that feeling, that need, in some other way. By contrast, if you’re taking morphine, the sensation is one of calmness and serenity. That might be compensating for some radically different need that has been repressed.

Monkeys that have been raised without attachment to a mother or a father are very different from monkeys that have had normal social attachment and touch early in life. They have a different stress response; their startle response is dramatic, their cortisol levels shoot up in response, for example, to a loud sound. And, interestingly, they’re more likely to consume ethanol if it’s available than an animal that had normal social attachment to a caregiver.

There are countless examples of this, where a lack of touch or other basic physical need leads to problematic development.

RD: What about early childhood trauma? How does that impact brain development and later drug- or pleasure-seeking behavior?

GW: A great deal of data suggests that a traumatic event early in life – the death of a parent or a loved one, physical abuse, a whole slew of things – can impact brain development. Even brief periods of trauma, at the right time, can permanently shift brain development in a way that seems to carry on through adulthood. People who have
experienced childhood trauma are more likely to have lower tolerance for stress, increased susceptibility to major depressive disorders or general anxiety disorder,
and increased sensitivity to drug addiction. It seems they are compensating for repressed needs early in life.

Sometimes people can find ways to compensate for unmet needs in a
positive way, but there’s certainly ample evidence that people compensate in a negative way.

RD: Knowing what you know about the often-deleterious ways humans compensate for unmet needs, what might you change in our current social and political systems?

GW: I would make them be more harmonious with the biology of brain development.
Let’s take a school setting as an example. In most schools, the classroom is set up so that children are sitting in rows, directed to the front of the class to the teacher. The teacher is the central cast member, and the emphasis is on getting through the lessons in almost an
algorithmic way.

But I wonder if that’s the best way to teach younger children. Kindergarten through fifth grade is a time when you want to foster the need for self-stimulation and self-creativity. What would happen if learning were more self-directed, so children spent more time in self-exploration and less time just sitting there passively, focusing on a teacher and taking it all in? A self-directed approach would be more natural and consistent with brain development.

Certainly there has to be a balance, and logistically there are reasons why schools are set up as they are. But that would be one area in which biological brain development might dictate policy and practice, at least in part.

Knowledge of brain development and the role of repressed needs might also lead us to respond differently to people on the fringe of society; if we understood where their behaviors were coming from we might respond in a more effective and more compassionate way.

RD: Give us an example.

GW: Let’s say, for example, people who have a particular fondness for tattoos, or thrill-seeking people who are drawn to extreme sports. These people are just expressing their core preferences, their pleasure instinct, in very novel ways.

The same goes for the various kinds of addictions. We typically think of addiction in terms of drugs and alcohol, but we can also include addictions to gambling, shopping, video games, television and so forth. All these things can be rooted in the same common circuitry that we all share. Knowing that might give me more sensitivity to other people’s expressions of their basic needs.

It’s also interesting to note that some of what we call fringe behaviors might be entirely acceptable in one culture or era and not acceptable in another. For example, in 1920s America, alcohol consumption was prohibited; the same level of drinking might be acceptable and even expected in other eras and cultures.

After doing the research for this book, and gaining a greater understanding of brain development, I have a healthy respect for the diversity of ways people satisfy basic biological needs. I also understand now that certain behaviors might be colored by cultural expectations or norms, but they stem from something much deeper than the cultural origins.

RD: Did you grow up in a religious household?

GW: It was a mixed household. My father was Jewish and my mother is Irish Catholic, so I had a little bit of both. Now, strangely enough, I’ve been practicing Buddhism for about 10 years. It seems to be the one religion that makes it easier for me to reconcile my faith and the scientific side of things.

Nichiren Buddhism, which my wife and I follow, doesn’t ask for the leap of faith other religions seem to demand.

I think it’s unfortunate that religion, especially in western cultures, seems to be in direct contrast with science. Buddhism seems to really want you to seek your own evidence; in that sense it’s similar to science.

RD: Before you began practicing Buddhism, did you struggle to reconcile the worlds of science and spirituality?

GW: I did. I understood that Christianity is a belief system that provides a profound
experience for millions of people. However, when I would try to reconcile the church’s dogma with scientific evidence, I found it extremely challenging. It’s a slightly different approach in Buddhism. The faith itself demands inquiry, and asks that you question your
environment.

RD: I think, as a society, our image of the ideal spiritual person is a monk, a priest, an imam – an austere person who has taken some vow of restraint, like celibacy or poverty. But vowing to deny yourself essential forms of pleasure is starkly in contrast to the scientific findings you’ve been talking about.

GW: I think that image, that spiritual ideal of an ascetic, is driven by many ideals, including the desire to shun the excesses of the modern world. For me, it’s all a question of balance. When I think of a Buddhist monk sitting in meditation, I think of somebody trying to be more centered and focused inward. But at its extreme – someone who has
become isolated and is not interacting with people at all – it’s not healthy in terms of neurological function.

And I don’t think that icon, of the ascetic, represents a healthy view of religion, either. To survive and thrive, I think a religion has to be a social medium. When we think of a modern religious icon – say, Mother Theresa, or the Dalai Lama – we think of people who are clearly embedded in a social culture. Maybe they’re not having some of their basic needs met – if they take a vow of celibacy, for example – but their biological needs for human touch and interaction are being met. Maybe a monk, for example, has no sexual interaction with others, and even minimal physical contact, but he is expressing himself and being stimulated in other ways. He might be painting, for example, or engaged in other positive interests or pursuits that compensate for the lack of sexual needs being met.

RD: Religious icons aside, it seems that religion has traditionally encouraged, even enforced, restraint of gratification, requiring of a person that she or he not satisfy his or her desires. How does that play out in society?

GW: There could be several ways, if you’re in a certain religious environment, and you have a need to express or experience something, and that need is being repressed, you have to find another way to get that need met, either by compensating for it in a healthy way, or expressing it covertly. This occurs in cultural and political systems as well.
Again, in the 1920s, the cultural opposition to alcohol consumption resulted in
the era of prohibition.

RD: And then the pendulum swung back the other way, and alcohol became acceptable again. And in the 1960s, even drug use was acceptable, even encouraged in some areas of society.

GW: That’s true. You’ll see that throughout history, in many cultures and eras. The pendulum swings to one extreme, and then the other. But what doesn’t change is the basic need underlying the expression. There is always a basic need to satisfy certain
elements of the pleasure instinct. And if those needs aren’t met, and they’re not compensated for in other ways, it can result in significant damage to normal brain development and maturation. These are important points. Though these discussions become almost philosophical in nature, there are real, day-today, political and social implications. It’s worth bringing a biological perspective into any discussions of policy making in terms of schools, societies, and national and international politics. We can thus
respond in a more realistic, sensitive and effective manner to problems in our world.