Dopamine

Having just read "How We Decide", I'm scrambling to jot down a few take-aways for a book so chalked-full of fascinating bits of research. How come Pysch was not this exciting in university?

The author, Jonah Lehrer  talks about the role of emotions in decision-making. Down-played and misunderstood for many years in favour of the rational and logic-based decision model, emotions are finally given the credit they deserve. That gut-instinct can actually be physiologically explained. Here's my "tell it to me like I'm ten" version:

The neurotransmitter dopamine basically controls all emotion, including pleasure. Think of the crack addict who's just gotten a fix -- major dopamine OD. The dopamine neurons of our brains are generating patterns based on experience. We learn what will give us pleasure and it's the expectation that actually fires dopamine, as well as the reward in getting what you expect. I think of Pavlov's dog -- the bell that rang before the treat was given taught the dog to salivate at the sound of the bell. The pattern was learned by dopamine neurons.

 

When the expectation is false (there is no treat), the brain generates an 'error-related' negativity signal -- also known as the "oh-shit circuit". The anterior cingulate cortex where all of this happens, helps remember what the dopamine cells are learning so that expectations can be adjusted in light of new info (e.g. there is no treat now, so stop expecting it when you hear the bell). That is how we learn from mistakes. Brilliant.

Motion sickness is due to this dopamine prediction error -- there is a conflict between the rocky experience and the expectation of solid ground, which results in nausea. Thankfully the dopamine neurons revise their model and the sensation goes away. Of course there are some of us that never learn from our mistakes ... we continue to make the same bad choices ... sigh. Wait, this is not about me.

 

One of the best parts of the book was how the author related this to PRAISE. Remember that famous experiment in which young children were administered a test -- half were praised for their effort and the other half were praised for their intelligence? The first group went on to tackle more challenging problems without missing a beat while the ones who were told they were smart choose easier tests and their confidence dropped along with their scores. These children were afraid of failure -- they felt pressure to continue to show they were smart. The smart compliment was in fact detrimental. Whereas the students who were praised for their effort felt the intrinsic reward of success. The 'smart' kids tried to bolster their own self-esteem by comparing their scores to those who did worse. But the kids praised for their effort were interested in those who scored higher. They wanted to understand their mistakes and learn how to do better. OMG, this hits close to home ...

Learning from mistakes is crucial -- unless your brain experiences the discomfort from being wrong again and again, it will never revise its model. Before your neurons can succeed, they must repeatedly fail. There are no short-cuts to this process. Brilliant!