Does Brain Science Disprove Freedom? Part 1
Tim O’Connor (Baylor University) explains recent neuroscientific experimentation by Benjamin Libet, which suggests that our actions are not free but physically determined by brain processes.
Well let me start with some questions about free will. There has been some recent work in neuroscience and in social psychology, which many scientists have interpreted as making trouble for traditional belief in free will and so I wondered if you could tell us a bit about some of this research, both the neuro-scientific research and the socio-psychological research and tell us your thoughts about it, what does it show?
There’s a lot of really fascinating work going on in both, as you say, neuroscience and social psychology. You can think of it as trying to get under the hood of how our brains work and in help shaping our behavior and people, of course, have known for centuries that the activity of our brains is relevant to how we choose and decide, people have known that if you get hit over the head with a hard, heavy object that’s probably going to affect your subsequent behavior.
Maybe cause you to become unconscious or worse. Beginning in the early ’80’s, a scientist by the name of Benjamin Libet devised a series of interesting studies that people thought had a very surprising, shocking implication.
The studies are very simple. You’re asked to sit in a room and to perform a simple behavior, so you already decide ahead of time what your behavior’s going to be. Maybe just lift your right index finger and wiggle it. And, you’re asked to do this within a 20-30 second interval of time, but crucially you’re not to plan ahead of time exactly when you’re going to do it. The goal is for you to spontaneously decide when you shall wiggle your finger.
And, while you’re waiting for the impulse to do this, you’re watching a clock, fixed on a wall, that’s not an ordinary clock, it has a very fast moving dial that goes a few times per second. And, you’re asked to notice the first moment at which you felt the impulse to go ahead and wiggle your finger, and to notice where the dial on that clock was at that moment. And, of course, observation of the clock, light signals, all that takes a bit of time. Scientists know how to adjust for that, right?
To try to zero in on when you felt was the actual moment at which you felt this urge to wiggle your behavior and then the surprising thing was that for almost a half second prior to the time you said you felt the impulse, there was a steady buildup of electrical activity in the cerebral cortex that they call the readiness potential, that some scientists interpreted as the brain preparing to trigger the relevant behavior.
And so, the interpretation that Benjamin Libet put on this was that your brain had decided before you consciously had decided to go ahead and move your finger. And so, what your sense of impulse was actually a product of an unconscious sub-personal physical decision event. And so, if that’s the correct interpretation, and crucially, if the Libet type experiment generalizes to the kind of decision making we make naturally outside of experimental context then the implication would be that we’re deceived when we think we autonomously consciously decide when to act. It’s somehow encoded in unconscious brain processes.