In the meantime, here is the original version of a column I wrote, which, after some peculiar mangling by the editors, was recently published in the local student paper. Readers of this blog will find the text annoyingly simplistic, or at least old hat; I post it here simply to stress that I would never - ever - make such use of question- and exclamation-marks.
The most important thing in life
Christopher Harris
What fascinates me most about the brain is its motivation, the fact that it wants and desires. I'm also acutely aware of the limits of my own free will: eat less, exercise more, study more, be more social, dare to do this, stop doing that; it's like a never-ending struggle with my own will, and I know I'm not the only one frustrated by this experience, especially now, with new year's resolutions failing left and right. So what's going on?
In the middle of your brain you have half a million neurons that release dopamine into your frontal lobes. These neurons form the core of your brain's reward system, which generates your motivation. Rewards, like food, drink, play, sex and addictive drugs, raise dopamine concentrations in your brain, as do learned rewards like money. Unexpected rewards are particularly effective, and dopamine builds up in anticipation of uncertain rewards, making everyone at the bus stop stare at the bend where the bus will appear. Low dopamine concentrations on the other hand make you distracted and disinterested.
Different behaviours are produced by different groups of neurons in the frontal lobes. These neuronal groups run on dopamine, and so the behaviour you feel most motivated to perform at any given moment is that of the group that generates the most dopamine. Eating sweets is easy: with a few simple muscle movements it activates your dopamine neurons through your taste buds. Studying for a distant exam is hard: it requires your full attention and activates your dopamine neurons only indirectly, through your prefrontal cortex, which simultaneously has to inhibit more immediate urges like surfing the web, going out or watching a film. You may have heard of Phineas Gage, who destroyed his prefrontal cortex in an accident and lost his impulse control and his ability to follow plans for the future.
New year's resolutions fail because we make them considering only the wonderful goal, which by itself produces plenty of dopamine, especially when it's new and feels like a fresh start. We don't realize how hard it will be for our prefrontal cortices to provide the new neuronal groups with enough dopamine to make us runregularly, or read in the library, or go to the gym, or in any way compete with the entrenched neuronal groups that have us sit on the couch, or over-eat, or smoke. On a normal day, the further away a goal is, the less attractive it seems, because the further away a reward is, the less dopamine it generates. So the trick to keeping new year's resolutions: be nice to your prefrontal cortex.
There's more to motivation of course, the reward system is enormously complex. This is how I like to think about it though, and it's worked so far. It helped me quit smoking, knowing that the urge was strong because dopamine neurons are covered in nicotine receptors, but that the brain would 'forget' this in a few months and the urge would go away. It helps me understand all kinds of thoughts, habits, excitements and hang-ups. It helps me understand my own brain. Check in next week for another bit of this story, and join the dopamine fan page on Facebook for references and more information.
See you February.
