How does your brain make decisions?

 In Decision-making, Insights, Science

When I was 18 I decided to study psychology, for a simple reason. I’d decided that the human brain was the most complex thing in the universe so I wanted to try and understand how it worked. Now, a few years later, and my speciality is the psychology of decision-making. Here are two fascinating developments in understanding how your brain makes decisions.

brainFirst up, neuroscience. From a brain imaging viewpoint, what tends to happen is that many areas of the brain work on the problem simultaneously. And each area computes different parts of the problem while the pre-frontal cortex  tends to amalgamate all the data from the other parts of the brain and make the decisions. What this feels like as a human, is that it can be hard to make your mind up as different parts of your brain are reaching different conclusions. For example, one part might be dealing with risks and fear, while another part might be dealing with interpersonal/social implications The brain is in essence arguing with itself. So, if you’ve ever been “in two minds” – the truth is, you most likely literally were. Once you understand this, it becomes ok – even a good thing – to feel indecisive at times, as long as then you consciously take steps to counter the indecision.

The other area which I find interesting is the role of chemical neurotransmitters and how they can control our mood. The most commonly mentioned are dopamine and serotonin. The effects of varying chemical levels in your brain are most clearly demonstrated by our attitude to risk changing according to how happy vs irritable we are feeling. One of my favourite studies is of Israeli judges looking at parole cases. They typically look at say 20 cases a day, and the prisoners chance of getting parole is massively influenced by whether the judge is tired, hungry or worst of all, both. First thing in the morning the chance of parole is around 60-70%, but at the end of the afternoon when the judge is tired and hungry, the chance of parole is down to 10%.

This isn’t just judges though, research shows that due to varying levels of brain chemicals, we make much more risk averse decisions in the afternoon, or even avoid making decisions altogether. So, if you want to get an optimistic, risk-appropriate decision, do it first thing in the morning. Here’s a video by Professor Baba Shiv which explains it in 4 minutes.

So, my two tips on managing your own brain:

First, accept the feeling of being in two minds, but put steps in place to move forward.

Second, plan a time in your day to make big decisions, usually as early in the morning as you can.

Posted by Rob Pyne