• Your brain loves rewards—whether you like it or not

    In the 1940s, two researchers named James Olds and Peter Milner accidentally uncovered some peculiar properties of a special area of the brain. The researchers implanted electrodes in the brains of lab mice that enabled the mice to give themselves tiny electric shocks to a small area called the nucleus accumbens. The mice quickly became hooked on the sensation.

    Olds and Milner demonstrated that the lab mice would forgo food, water, and even run across a painful electrified grid for the opportunity to continue pressing the lever that administered the shocks. A few years later, other researchers tested human response to self-administered stimulus in the same area of the brain. The results were just as dramatic as in the mouse trial — subjects wanted to do nothing but press the brain-stimulating button. Even when the machine was turned off, people continued pressing the button. Researchers even had to forcibly take the devices from subjects who refused to relinquish them.

    Given the powerful response demonstrated in these experiments on lab animals and later people, it's no wonder companies stimulate consumers' nucleus accumbens all the time. For example, the reason we find ourselves incessantly checking our smart phones is deeply rooted in the psychology of reward.

    The Stress of Desire

    Olds and Milner concluded that they had discovered the brain's pleasure center. In fact, we now know that other things that feel good also activate the same neural region. Sex, delicious food, a bargain, and of course, our digital devices, all tap into this deep recess of the brain, providing the impetus for many of our behaviors.

    However, more recent research has shown that Olds and Milner's experiments were not stimulating pleasure per se. Stanford Professor Brian Knutson, conducted a study exploring blood flow in the brains of people wagering while inside of an fMRI machine.

    The test subjects played a gambling game while Knutson and his team looked at which areas of their brains became more active. The startling results showed that the nucleus accumbens was not activating when the reward (in this case a monetary payout) was received, but rather, in anticipation of it.

    The study revealed that what draws us to act is not the sensation we receive from the reward itself, but the need to alleviate the craving for that reward. The stress of desire in the brain appears to compel us, just as it did in Olds' and Milner's lab mouse experiments.