Where Did Free Will Go? — Prof. Pete Redgrave — 16th March 2015

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.

  1. How to stay alive – to avoid harm and main­tain life.
  2. 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!