When we feel desire, we experience it physically. Our vision becomes more focused, our bodies tense, our stomachs tighten, and the craving is almost painful. When we experience pleasure, our bodies relax, our sight blurs and time passes more slowly.
Despite their differences, these two emotional states work in tandem. Each experience of pleasure quenches the thirst elicited by desire. At the same time, it kindles our brains to desire more of the same. In this way, these two systems balance each other and become our guides through the choices we have to make in life.
Sense of satisfaction
Modern neuroscience has identified how this equilibrium can go off kilter and wreak havoc on our existence. This is revealed through the behaviour and biology of drug addicts. The first dose of cocaine or heroin produces an intense wave of pleasure. This initial experience is almost never matched again, yet the desire for the drug increases with use, triggering a desperate and futile pursuit for more of that elusive pleasure. How can that be?
Desire is driven by the release of dopamine, a chemical transmitter in the brain that prepares the mind and body for action. Like cocaine, which sets off a powerful dopamine rush, this release gives us a sense of energy and power, enabling us to assert ourselves with others and to strive for the objects of our desire — be they food, weapons or a sexual partner.
Meanwhile, pleasure neurones depend on endorphins. These tiny molecules secreted by the brain have an effect similar to opium, inducing a powerful feeling of calm and serenity, a sense of satisfaction and a state devoid of desire that normally occurs when desire is sated.
All this is thrown out of kilter when artificial stimulants upset the natural sequence between the two systems. Drugs, pornography, cigarettes and even ice-cream produce an immediate rush, by stimulating the pleasure system, that is out of proportion to any effort made to obtain them. In nature, such rewards are obtained only after considerable expenditures of mental and physical energy. This mismatch creates the conditions for craving — a state in which desire can keep increasing, even while pleasure steadily decreases.
For the past 2,500 years, Buddhism has stressed the importance of maintaining harmony between desire and contentment. Desire is positive when it is under control and the object we desire is within our reach. When this is the case, desire becomes a source of energy and not a negative or destructive force. In meditation, harmony is established by breathing. The desire and anticipation of the next breath is followed by the pleasure of its fulfilment. This simple pleasure is available to us for as long as we live and breathe.
Today, as in the time of the Buddha, the balance between pleasure and desire remains a fundamental key to our emotional stability. Neuroscience has simply shed some new light on exactly how it operates.