The psychological roots of resource overconsumption

May 10, 2011 Comments Off on The psychological roots of resource overconsumption by

The psychological roots of resource overconsumption

Nate Hagens

Humans have an innate need for status and for novelty in their lives. Unfortunately, the modern world has adopted very energy- and resource-intensive ways of meeting those needs. Other ways are going to have to be found as part of the move to a more sustainable world.

Most people associate the word “sustainability” with changes to the supply side of our modern way of life such as using energy from solar flows rather than fossil fuels, recycling, green tech and greater efficiency. In this essay, however, I will focus on the demand-side drivers that explain why we continue to seek and consume more stuff.

When addressing ‘demand-side drivers’, we must begin at the source: the human brain. The various layers and mechanisms of our brain have been built on top of each other via millions and millions of iterations, keeping intact what ‘worked’ and adding via changes and mutations what helped the pre-human, pre-mammal organism to incrementally advance. Brain structures that functioned poorly in ancient environments are no longer around. Everyone reading this page is descended from the best of the best at both surviving and procreating which, in an environment of privation and danger where most ‘iterations’ of our evolution happened, meant acquiring necessary resources, achieving status and possessing brains finely tuned to natural dangers and opportunities.

This essay outlines two fundamental ways in which the evolutionarily derived reward pathways of our brains are influencing our modern overconsumption. First, financial wealth accumulation and the accompanying conspicuous consumption are generally regarded as the signals of modern success for our species. This gives the rest of us environmental cues to compete for more and more stuff as a proxy of our status and achievement. A second and more subtle driver is that we are easily hijacked by and habituated to novel stimuli. As we shall see, the prevalence of novelty today eventually demands higher and higher levels of neural stimulation, which often need increased consumption to satisfy. Thus it is this combination of pursuit of social status and the plethora of novel activities that underlies our large appetite for resource throughput.


Evolution has honed and culled ‘what worked’ by combining the substrate of life with eons’ worth of iterations. Modern biological research has focused on the concept of ‘relative fitness’, a term for describing those adaptations that are successful in propelling genes, or suites of genes, into the next generation and that will have out-competed those that were deleterious or did not keep up with environmental change. Though absolute fitness mattered to the individual organisms while they were alive, looking back it was ‘relative fitness’ that shaped the bodies and brains of the creatures on the planet today.

Status, both in humans and other species, has historically been a signaling mechanism that minimised the costs of competition, whether for reproductive opportunities or for material resources. If you place ten chickens in an enclosure there will ensue a series of fights until a pecking order is established. Each bird quickly learns who it can and cannot beat and a status hierarchy is created, thus making future fights (and wastes of energy) less common. Physical competition is costly behaviour that requires energy and entails risk of injury. Status is one way to determine who one can profitably challenge and who one cannot. In our ancestral environment, those men (and women) that successfully moved up the social hierarchy improved their mating and resource prospects. Those at the bottom of the status rung did not only possess fewer mating opportunities but many did not mate at all. Status among our ancestors was probably linked to those attributes providing consistent benefits to the tribe: hunting prowess, strength, leadership ability, storytelling skills etc. In modern humans, status is defined by what our modern cultures dictate. As we are living through an era of massive energy gain from fossil fuels, pure physical prowess has been replaced by digital wealth, fast cars, political connections, etc.

It follows that the larger a culture’s resource subsidy (natural wealth), the more opportunity there is for ‘status badges’ uncorrelated with basic needs such as strength, intelligence, adaptability, stamina, etc. Though ‘what’ defines status may be culturally derived, status hierarchies themselves are part of our evolved nature. Ancestral hominids at the bottom of the mating pecking order, ceteris paribus, are not our ancestors. Similarly, many of our ancestors had orders of magnitude more descendants than others. For example, scientists recently discovered an odd geographical preponderance for a particular Y chromosome mutation which turns out to be originally descended from Genghis Khan. Given the 16 million odd male descendants alive today with this Y marker, Mr. Khan is theorised to have had 800,000 times the reproductive success than the average male alive on the planet in 1200 AD. This does not imply that we are all pillagers and conquerors — only that various phenotypic expressions have had ample opportunity to become hardwired in our evolutionary past. [1]

Mating success is a key driver in the natural world. This is all studied and documented by evolutionary research into the theory of “sexual selection”, which Charles Darwin once summarised as the effects of the “struggle between the individuals of one sex, generally the males, for the possession of the other sex.” [2] Biologists have shown that a primary way to reliably demonstrate one’s ‘quality’ during courtship is to display a high-cost signal — e.g. a heavy and colourful peacock’s tail, an energy-expending bird-song concert, or a $100,000 sports car. [3] These costly “handicap” signals are evolutionarily stable indicators of their producer’s quality, because cheap signals are too easy for low-quality imitators to fake. [4]

In this sense ‘waste’ was an evolutionary selection! Think of three major drawbacks to a male peacock of growing such a hugely ornate tail:

  1. the energy, vitamins and minerals needed to go into the creation of the tail could have been used for other survival/reproductive needs,
  2. the tail makes the bird more likely to be spotted by a predator,
  3. If spotted, the cumbersome tail makes escape from a predator less likely.

Overall, though, these negative “fitness hits” must have been outweighed by the drab female peahen’s preference for males with larger, more ornate tails. With this filter, we can understand the rationale and prevalence of Veblen goods (named after the 19th-century economist who coined the term ‘conspicuous consumption’) — a group of commodities that people increasingly prefer to buy as their price gets higher because the greater price confers greater status. This biological precept of signalling theory is alive and well in the human culture.


Modern man evolved from earlier hominids under conditions of privation and scarcity at least until about 10,000 years ago. The period since then has been too short a time to make a significant change to millions of years of prior neural sculpture. Nature made the brain’s survival systems incredibly efficient. The brain is based on about 40% of all our available genes and consumes over 20% of our calorific intake. Incremental changes in how our brains recognise, process and react to the world around us either contributed to our survival and thus were carried forward, or died out.

Some changes affected salience, the ability to notice what is important, different or unusual. Salience recognition is part of what’s called the mesolimbic dopamine reward pathway. This pathway is a system of neurons integral to survival efficiency, helping us to instantly decide what in the environment should command our attention. Historically, immediate feedback on what is ‘new’ was critical to both avoiding danger and procuring food. Because most of what happens around us each day is predictable, processing every detail of a familiar habitat wastes brain energy. Such activity would also slow down our mental computer so that what are now minor distractions could prove deadly. Thus our ancestors living on the African savanna paid little attention to the stable mountains on the horizon but were quick to detect any movement in the bush, on the plains, or at the riverbank. Those more able to detect and process ‘novel cues’ were more likely to obtain rewards needed to survive and pass on their suites of genes. Indeed, modern experimental removal of the (dopamine) receptor genes in animals causes them to reduce exploratory behaviour, a key variable related to inclusive fitness in animal biology. [5]

We are instinctually geared for individual survival — being both reward-driven, and curious. It was these two core traits that the father of economics himself, Adam Smith, predicted in The Wealth of Nations would be the drivers of world economic growth. According to Smith, uniting the twin economic engines of self-interest (which he termed self-love) and curiosity was ambition — “the competitive human drive for social betterment”. About 70 years later, after reading Adam Smith’s Theory of Moral Sentiments, Charles Darwin recognised the parallel between the pursuit of wealth in human societies and the competition for resources that occurred among animal species. Our market system of allocating resources and ‘status’ can therefore be seen as the natural social culmination for an intelligent species finding an abundance of resources.

But, as we shall soon see, the revered Scottish philosopher could not have envisioned heli-skiing, Starbucks, slot machines, Facebook, email and many other stimulating and pleasurable objects and activities that people engage in today and to which they so easily become accustomed.

The mesolimbic dopaminergic reward system

“Americans find prosperity almost everywhere, but not happiness. For them desire for well-being has become a restless burning passion which increases with satisfaction. To start with emigration was a necessity for them: now it is a sort of gamble, and they enjoy the sensations as much as the profit.” Alexis de Tocqueville, Democracy in America 1831

Traditional drug abuse happens because natural selection has shaped behaviour-regulation mechanisms that function via chemical transmitters in our brains. [6] Addicts can become habituated to the feelings they get from cocaine, heroin or alcohol, and they need to increase their consumption over time to get the same neurotransmitter highs. This same neural reward architecture is present in all of us when considering our ecological footprints: we become habituated via a positive feedback loop to the ‘chemical sensations’ we receive from shopping, keeping up with the Joneses (conspicuous consumption), pursuing more stock profits, and myriad other stimulating activities that a surplus of cheap energy has provided.

An explosion of neuroscience and brain-imaging research tells us that drugs of abuse activate the brain’s dopamine reward system that regulates our ability to feel pleasure and be motivated for “more”. When we have a great experience — a glance from a pretty girl, a lovemaking romp in the woods, a plate of fresh sushi, hitting 777 on a one-eyed bandit, catching a lunker pike, watching a sunset, hearing a great guitar riff etc. — our brain experiences a surge in the level of the neurotransmitter dopamine. We feel warm, ‘in the zone’ and happy. After a while, the extra dopamine gets flushed out of our system and we return to our baseline level. We go about our lives, looking forward to the next pleasurable experience. But the previous experience has been logged into our brain’s limbic system, which, in addition to being a centre for pleasure and emotion, holds our memory and motivation circuitry. [7] We now begin to look forward to encores of such heady stimuli and are easily persuaded towards activities that promise such a chemical reprise. These desires have their beginnings outside our conscious awareness. Recent brain-imaging research shows that drug and sexual cues as brief as 33 milliseconds can activate the dopamine circuitry, even if a person is not conscious of the cues. Perhaps there are artistically shaped sexual images hidden in advertisements for whiskey after all…

Historically, this entire system evolved from the biological imperative of survival. Food meant survival, sex meant survival (of genes or suites of genes), and additional stockpiles of both provided success relative to others, both within and between species. There was a discrete payoff to waiting hours for some movement in the brush that signaled ‘food’, or the sound of a particular bird that circled a tree with a beehive full of honey, etc. Our pattern recognition system on the Pleistocene would have been a grab-bag of various environmental stimuli that ‘excited’ our brains towards action that correlated with resources (typically food). In sum, the brain’s reward pathways record both the actual experience of pleasure as well as ensuring that the behaviours that led to it are remembered and repeated. Irrespective of whether they are ‘good’ for the organism in the current context — they ‘feel’ good, which is the mechanism our brain has left us as a heritage of natural selection.

The (very important) mechanism of habituation

Habituation — getting used to something — and subsequent substance abuse and addiction develops because of the way we learn. Learning depends crucially on the discrepancy between the prediction and occurrence of a reward. A reward that is fully predicted does not contribute to learning. [8] The important implication of this is that learning advances only to the extent to which something is unpredicted and slows progressively as a stimuli becomes more predictable. [9] As such, unexpected reward is a core driver in how we learn, how we experience life, and how we consume resources.

Dopamine activation has been linked with addictive, impulsive activity in numerous species. Dopamine is released within the brain not only to rewarding stimuli but also to those events that predict rewards. It has long been known that two groups of neurons, in the ventral tegmental and the substantia nigra pars compacta areas, and the dopamine they release, are critical for reinforcing certain kinds of behaviour. Neuroscientist Wolfram Schultz measured the activity of these dopamine neurons while thirsty monkeys waited for a tone which was followed by a squirt of fruit juice into their mouths. After a series of fixed, steady amounts of juice, the volume of juice was suddenly doubled. The rate of neuron firing went from about 3 per second to 80 per second. But after several trials, after the monkeys had become habituated to this new level of reward, their dopamine firing rate returned to the baseline rate of 3 firings per second after the squirt of juice. The monkeys had become habituated to the coming reward! The opposite happened when the reward was reduced without warning. The firing rate dropped dramatically, but eventually returned to the baseline rate of 3 firings per second. [10]

The first time we experience a drug or alcohol high, the amount of chemical we ingest often exceeds the levels of naturally occurring neurotransmitters in our bodies by an order of magnitude. [11] No matter how brief, that experience is stored in our neural homes for motivation and memory — the amygdala and hippocampus. Getting drunk with your friends, getting high on a ski-lift, removing the undergarments of a member of the opposite sex for the first time — all initially flood the brain with dopamine alongside a picture memory of the event chemically linked to the body’s pleasurable response to it. As such we look forward to doing it again, not so much because we want to repeat the activity, but because we want to recreate that ‘feeling’.

But in a modern stimuli-laden culture, this process is easily hijacked. After each upward spike, dopamine levels again recede, eventually to below the baseline. The following spike doesn’t go quite as high as the one before it. Over time, the rush becomes smaller, and the crash that follows becomes steeper. The brain has been fooled into thinking that achieving that high is equivalent to survival and therefore the ‘consume’ light remains on all the time. Eventually, the brain is forced to turn on a self-defence mechanism, reducing the production of dopamine altogether — thus weakening the pleasure circuits’ intended function. At this point, an ‘addicted’ person is compelled to use the substance not to get high, but just to feel normal — since one’s own body is producing little or no endogenous dopamine response. Such a person has reached a state of “anhedonia”, or inability to feel pleasure via normal experiences. Being addicted also raises the risk of having depression; being depressed increases the risk of self-medicating, which then leads to addiction, etc. via positive feedback loops.

In sum, when exposed to novel stimuli, high levels of curiosity (dopamine) are generated, but it is the unexpected reward that causes their activation. If I order a fantastic array of sushi and the waiter brings me a toothpick and my check, I am going to have a plunge in dopamine levels which will create an immediate craving for food. It is this interplay between expected reward and reality that underlies much of our behavioural reactions. Ultimately, as it relates to resource consumption, repeated use of any dopamine-generating ‘activity’ eventually results in tolerance. Withdrawal results in lower levels of dopamine and continuous use is required to keep dopamine at normal levels, and even higher doses to get the ‘high’ levels of initial use. Consumers in rich nations are arguably reaching higher and higher levels of consumption tolerance. If there was such a thing as ‘cultural anhedonia’, we might be approaching it.

America and addiction

It would be pretty hard to be addicted directly to oil; it’s toxic, slimy and tastes really bad. But given the above background, we can see how it is possible to become addicted to the energy services that oil provides. Humans are naturally geared for individual survival — curious, reward-driven and self-absorbed —but modern technology has now become a vector for these cravings. Material wealth and the abundant choices available in contemporary US society are unique in human (or animal) experience; never before in the history of our species have so many enjoyed (used?) so much. Within a culture promoting ‘more’, it is no wonder we have so many addicts. High-density energy and human ingenuity have removed the natural constraints on our behaviour of distance, time, oceans and mountains. For now, these phenomena are largely confined to developed nations — people living in a hut in Botswana or a yurt in Mongolia cannot as easily be exposed to the ‘hijacking stimuli’ of an average westerner, especially one living in a big city in the West, like London or Los Angeles.

Many activities in an energy-rich society unintentionally target the difference between expected and unexpected reward. Take sportfishing for example. If my brother and I are on a lake fishing and we get a bite, it sends a surge of excitement through our bodies — what kind of fish is it? How big is it? etc. We land an 8-inch perch! Great! A minute later we catch another 8 inch perch — wow, there must be a school! After 45 minutes of catching nothing but 8-inch perch, our brain comes to expect this outcome, and we need something bigger, or a different species, to generate the same level of excitement, so we will likely move to a different part of the lake in search of ‘bigger’ and/or ‘different’ fish. (Though my brother claims he would never tire of catching fish 8-inch perch I think he’s exaggerating). Recreational fishing is benign (if not to the fish), but one can visualise other more resource-intensive pastimes activating similar circuitry. New shoes, new cars, new vacations, new home improvements, new girlfriends are all present on the modern unexpected reward smorgasbord.

The habituation process explains how some initially benign activities can morph into things more destructive. Weekly church bingo escalates to $50 blackjack tables; the Sports Illustrated swimsuit edition results, several years down the road, in the monthly delivery (in unmarked brown packaging) of Jugs magazine or webcams locked in on a bedroom in Eastern Europe; youthful rides on a rollercoaster evolve into annual heli-skiing trips, etc. The World Wide Web is especially capable of hijacking our neural reward pathways. The 24/7 ubiquity and nearly unlimited options for distraction on the internet almost seem to be perfectly designed to hone in on our brains’ g-spot. Shopping, pornography, gambling, social networking, information searches, etc. easily out-compete the non-virtual, more mundane (and necessary) activities of yesteryear. Repetitive internet use can be highly addictive, though psychiatrists in different countries are debating whether it is a true addiction. For better or worse, the first things I do in the morning is a) check what time it is, b) start the coffee machine then c) check my e-mail, to see what ‘novelty’ might be in my inbox. Bills to pay, and e-mails from people who are not important or interesting, wait until later in the day, or are forgotten altogether.

There are few healthy men on the planet today who do not respond in social settings to the attention of a high-status, attractive 20- to 30-something woman. This is salient stimuli, irrespective of the man’s marital status. But here is one example of where nature and nurture mesh. Despite the fact that 99+% of our history was polygynous, modern culture precludes men from running around pell-mell chasing women; we have rules, laws, and institutions such as marriage