Neurophilosophy and Free Will

What is the neurobiological side of free will? Which factors enhance or undermine self-control? How could neurophilosophy complicate criminal law? Patricia Smith Churchland, UC President’s Professor of Philosophy Emerita at the University of California, discusses various aspects underlying control, free will and responsibility.

Philosophers ask the question, “Are we ever really in control of our actions?” If, as we think, choices and decisions are the outcome of the physical brain and how it works, that probably seems to mean that our decisions and choices are caused by antecedent conditions of the brain. So, people have said, “Can you ever be considered really in control if your brain is a causal machine?” That is kind of a current take on the question of free will.

Self-control can be undermined not just by things like extreme hunger and extreme exhaustion; it can be undermined by drugs. A huge effort around the world has gone into understanding the neurobiology of addiction and the main addictive chemicals, that people have studied, involve cocaine, heroin, nicotine, and alcohol. What is known now is that there are very specific physical changes in the reward system, in the basal ganglia, and it sometimes looks as though those very specific changes actually are quite permanent. So, understanding addiction is very closely related to understanding the nature of self-control.

Mice have a very fast development relative to humans. But there are one or two days when they are adolescents before they actually become adults. So, people have tested their risk-taking behaviour during that adolescent period. One of the things that they find is that adolescent mice will run on an elevated maze, which normally adult and baby rats do not like to do – they fear falling off. But adolescents, especially in the company of others, are quite happy to run on an elevated maze – they will take a risk. It has also been found that adolescent mice will binge drink alcohol, if given the opportunity, especially when there are others around. I think what these results suggest is that there is something about risk-taking in the adolescent brain that we really need to understand in the present context of the political world we live in and ask why young people are willing to take extraordinary risks: join a motorcycle gang, join ISIS, or meet up with their mates and beat up other soccer fans.