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Insights from 20 decision blogs

Thank you for joining me for blog 21 in the series, highlighting decision-making and the brain. This is my public exploration of what drives decision-making and how we can use that information to make better decisions, resulting in better outcomes.

I have been asked the question 'what have you learnt so far and where are you going next with this?' from people who have recently subscribed to the blog. So today's blog is an opportunity to review the key insights I have uncovered so far, and the areas of research I am planning for future blogs.

To make this readable I'm going directly into insights and will place links to previous blogs as a way for you to see the idea in more detail. We'll start with a mini-history of the brain.

The mini-history of the brain

Parts of our brain that evolved first in worms had a structure that had reward, movement and fear and were present 500million years ago. As worms evolved in fish an ancestor of ours developed a part of the brain that responds to dangerous situations. This early brain never went away, and we refer to this part of our brain as the old brain.

The 'new brain' was an additional structure that evolved around the old brain. It provided flexibility and capacity to respond to situations in a more nuanced way which aided complex social interaction and adaptation. Humans have a much larger new brain than other animals which gives them a particular advantage in adapting to new conditions.

The old brain ensures we continue to breathe, digest and have protective reflexes, whereas the new brain can help us learn language, play music, do puzzles. (The new brain is allowing you to read this blog).

There is some evidence that your old brain and new brain almost act like a committee of two where the old brain comes up with an answer and your new brain (if engaged) has veto rights to change the response. The brain - old and new (

Are we rational?

We are not purely rational beings. At best, we are sometimes rational. This is not a flaw but a feature of our brains.

To be rational, we are required to receive information, process it, store it and retrieve it, all the while ensuring that the logic and reason we use to make inferences is sound. This is energy intensive, slow and takes a lot of processing power. It just does not work for the estimated 35,000 decisions we make each day, and certainly does not work when we are in danger and need to take swift action. The constraints of decision-making (

To understand this feature of the brain we need to understand two physical drivers of how we got here:

1) We have evolved through maximising survival and reproductive fitness. There is a direct relationship between the amount of deliberate thinking we do (which take a lot of energy) and the amount of food we need. Our brain has evolved to be energy efficient to avoid us needing more food than there might be available.

2) Dangers need to be processed quickly. A quick and decisive 'good enough' action without much thinking is sometimes better than a slow and deliberate one.

These two factors mean that rationality in the sense we described above is not always practical. Our brain squares this by making heroic trade-offs, simplifications and assumptions. We have limited decision bandwidth. This produces predictable biases i.e. irrational decisions when viewed from a long term perspective.

Biases covered so far:

1) Jumping to conclusions: we can jump to conclusions and make decisions based on very flimsy evidence. Jumping to conclusions (

2) Decision inertia: we find it hard to change our mind - it requires more brain activity to reopen our thinking than stick with our original thoughts. Mental effort feels less comfortable than relying on an old rule of thumb. Change your mind! (

3) Framing and nudging: we can be encouraged to make different decisions by different presentations of the same facts, this is often used to market things to us or get us to buy the 'upgrade'. You've been framed (, Are you being nudged (or sludged)? (

4) Anchoring: we often get fixated on the starting point of any decision-making e.g. a starting point in a negotiation. Why you need an anchor (

5) Loss Aversion: we are so keen to avoid an individual financial loss, that we sometimes play it too safe, except when we are already underwater on an investment, when we sometimes take too much risk to play catch-up. Common financial biases (

How do we create a better environment for decision making

Decision-making, getting work done and learning seems to have common requirements.

1) We are at our best when fresh, sober and well nourished

2) We need to have determined that what we are about to do is a worthwhile priority and focus solely on that one task. Focusing on your most important decisions first ensures your limited decision bandwidth is focused on things that matter most.

3) We need to silence distractions, either by being constantly on a device, chatting to someone or even going through future and past events

4) Just get started and your focus will increase

5) Keep score on your decision-making to refine how you do

Types of internal distraction

People who have sub-optimal conditions for decision-making are more likely to avoid making the decision at all, procrastinate or make the most conservative decision.

Where next?

I'm currently researching brain chemistry and it is leading me to consider different brain chemicals (dopamine, oxytocin, endorphins, serotonin and cortisol). That will be the next series of blogs.

I will then go onto look at group dynamics, reacting to new evidence, good ways to get information and the power of stories.

Two unexpected areas that this has encouraged me to research are supernormal ways to learn and wisdom for the 21st century.

Which areas do you find interesting that I have not covered yet?

Books I recommend to read on this subject


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