Benjamin Libet's Work in Neuroscience and Choice

an excerpt

that before every such movement, there is a distinctive build-up of electrical activity in the brain. And this build-up happens about half a second before your conscious “decision” to move your arm. So by the time you think, “OK, I’ll move my arm,” your body is halfway there. Which means your conscious experience of making a decision – the experience associated with free will – is just a kind of add-on, an after-thought that only happens once the brain has already set about its business. In other words, your brain is doing the real work, making your hands turn the pages of this magazine or reach over for your cup of tea, and all the time your conscious mind is tagging along behind.

Cave likens this finding to discovering that, “after years of driving around in your car, . . . the steering-wheel is not attached to anything, and the car has been steering by itself.” Cave also summarizes related research finding that,
when asking [subjects] to choose to move either their left or right hands, it was possible to influence their choice by electronically stimulating certain parts of their brains. So, for example, the scientists could force the subjects always to choose to move their left hands. But despite their choice being electronically directed, these patients continued to report that they were freely choosing which hand to move.
Thus, even when someone else is driving our car, we attribute the car’s movements to our control. “Every time it turns left, you just move your toy steering wheel and think, ‘Ah yes, I want to turn left.’”
Those sorts of findings, Cave claims, have been further clarified with the aid of “modern neuro-imaging technology,” which has demonstrated that “our minds – our conscious, mental lives – are a product of activity in the brain,” and that, “even when we have the conscious experience of deciding, our brains have really already taken the decision for us. Free will is an illusion.”