We didn’t get where we are today by being positive you know. Oh no. Survival is a tough, uncompromising business. Our ancient ancestors needed the negativity bias that is neurally wired into our brains in order to be successful. And successful they were; the fact you are reading this today being proof of that. The paradox is that this very successful survival mechanism – ‘the negativity bias’ – can often get in the way of people being able to experience life positively.
Let’s look at a simple model of how the human brain has been built up over tens of thousands of years of evolution. (see also Rick Hanson’s article on this subject). We can think of it as being composed of three (evolutionary) layers:
1. The Lizard Brain This is the ‘old brain’. It shares many characteristics with the reptilian brain. It tends to fire in a reactive way. It is alert to dangers. One classic and well-know example that is often quoted is the ’emotional hijack’ – when our emotions take over and we can actually feel like we are at the mercy of another brain. In some ways that is true. When the ‘red mist’ falls across our eyes in moments of fury or fear, the lizard has taken over the controls.

source: http://www.sciencedirect.com
2. The Mammalian Brain The middle layer of the brain, which we share with other mammals (in an evolutionary sense) is much more concerned with seeking rewards. More sophisticated processing takes place at this layer than in the ‘old brain’, although in neuroplastic terms it is still relatively ‘rigid’.
3. The Primate/Human Brain The most recently developed, upper layer of the brains of primates and humans is concerned primarily with attachments and relationships. We see this most clearly in the use of communication, language, social network development and extracted thought concerned with abstract concepts such as philosophy, religion and science.
Some of the most recent advances in the science of neuroplasticity have started to reveal amazing abilities for the brain to change and alter shape (by creating new connections and thickening existing connections) as a result of experiences and repeated use. While neuroplasticity can, and does, take place at all three levels of the brain, it does appear that it is much more difficult to affect changes in the lizard brain than in the primate/human level (or neocortical region) of the brain. For a superb in-depth treatment of this area, I refer you to Rick Hanson, author of Buddha’s Brain.
Why is this important? Well, it means that, no matter how sophisticated and developed our thinking becomes, no matter how much we believe we have our emotions under control, there is, deep within our 21st Century selves, a part of us which is operating on one simple rule, which is basically “Get Lunch – Don’t Be Lunch!”
Now, even in the wild, most anxious episodes resolve fairly quickly. The highly attuned Continue reading