Brains began evolving millions of years ago.
All vertebrates (fish, frog, bird, monkey, man) have brains of the same design but in different species the brain’s size and sophistication depends on the characteristic that is most important to the species.
In humans it is thinking, in dogs smell, in dolphins sonar, in bats radar.
Why is it good to have a brain? The brain has to find a huge range of solutions to two basic questions.
- How to stay alive – to avoid harm and maintain life.
- How to reproduce to maintain the species.
In all vertebrate species this first question is taken care of by what is now called the ‘old brain’. This has fairly simple sections covering HUNGER, THIRST and FEAR all working together. e.g. A rabbit is eating grass (brain section HUNGER dominant). A wolf sees the rabbit (HUNGER dominates wolf’s brain) and the wolf attacks. The rabbit sees the wolf (now FEAR dominates the rabbit’s brain) and the rabbit runs.
The human brain is large and the cerebral cortex is very folded and grooved but in a goose the brain is small and the cortex is smooth. Humans have developed the ‘new brain’ in the elaborate cortex where more sophisticated solutions to the fundamental problems of life are found (so we recognise guns, fire, knives, bombs etc. as threats).
The ‘new brain’ is more adapted to a selected goal but the ‘old brain’ is driven by a selected stimulus.
As well as these responses there are responses that have been ‘learned’. These are responses to rewards and punishments. Often they are ‘taught’ by parents who reward their children for ‘good’ behaviour, or success, and punish them for ‘bad’ behaviour. We often do not respond to a stimulus as our ‘old brain’ would dictate because our learned response tells us that it is inappropriate. In other words, we do not use free will.
Addicts get pleasure from their addiction and often cannot overcome the section of the brain that urges them to crave that same high again. They do not have free will.
Prof. Redgrave thinks we do not become aware of a ‘decision’ we make until AFTER it has been made. The brain ‘decides’ without necessarily consulting us. He thinks that we have strong feelings that we are in control and that we are actually making choices but it is the part of our brain that SHOUTS LOUDEST that determines what we do. He also told us about neurons (nerve cells) and transmission of nerve impulses by neurochemicals, briefly explaining that Parkinson’s disease sufferers and schizophrenics and drug addicts are affected by interference with these chemicals in their brains.
The conclusion I came to from his talk was that I probably do not have free will, but then I’m married!