Mick Hartley

Here’s an article on an experiment purporting to show that we – our brains – make decisions before we’re consciously aware of them, thus casting doubt on the notion of free will. Yes, again:

“We think our decisions are conscious,” said neuroscientist John-Dylan Haynes at the Bernstein Center for Computational Neuroscience in Berlin, who is pioneering this research. “But these data show that consciousness is just the tip of the iceberg. This doesn’t rule out free will, but it does make it implausible.”

Through a series of intriguing experiments, scientists in Germany, Norway and the U.S. have analyzed the distinctive cerebral activity that foreshadows our choices. They have tracked telltale waves of change through the cells that orchestrate our memory, language, reason and self-awareness…

To probe what happens in the brain during the moments before people sense they’ve reached a decision, Dr. Haynes and his colleagues devised a deceptively simple experiment, reported in April in Nature Neuroscience. They monitored the swift neural currents coursing through the brains of student volunteers as they decided, at their own pace and at random, whether to push a button with their left or right hands.

In all, they tested seven men and seven women from 21 to 30 years old. They recorded neural changes associated with thoughts using a functional magnetic resonance imaging machine and analyzed the results with an experimental pattern-recognition computer program.

While inside the brain scanner, the students watched random letters stream across a screen. Whenever they felt the urge, they pressed a button with their right hand or a button with their left hand. Then they marked down the letter that had been on the screen in the instant they had decided to press the button.

Studying the brain behavior leading up to the moment of conscious decision, the researchers identified signals that let them know when the students had decided to move 10 seconds or so before the students knew it themselves. About 70% of the time, the researchers could also predict which button the students would push.

I find this very unconvincing. 10 seconds? That kind of gap suggests that there’s a problem with the way they’re measuring the moment when the decision became conscious. Which of course is always going to be a problem, because it’s not a black-and-white situation, and it may not be a “moment”. But 10 seconds is surely way too long to be plausible, and suggests that the whole experiment’s flawed.

Benjamin Libet was the man who pioneered this avenue of research, though the gaps he was reporting were of the order of half a second. I’ve posted about this before, here, and here. I don’t think any of this shows that we don’t have free will, though it may show that we’re not always conscious of our decisions. Even if the psychologists are right, and you can measure neurological signs of the decision prior to the awareness, it’s still our decision. We’re not just a spark of Cartesian awareness in a great mass of neurons. The neurons are us. Whatever part of me can be measured as showing a correlation with a decision, well, it’s still me making that decision, whether it’s neurons in my frontal lobe or a twitching tendon in my foot.

The way they describe this research is bizarre:

Such experiments suggest that our best reasons for some choices we make are understood only by our cells.

What a horribly confused sentence. As though it’s our cells which understand: get the relevant input, weigh the pros and cons, make the decision and then, some 10 seconds or so later, tell us, which is to say that little flicker of awareness stuck in the pineal gland or wherever.

It’s as though experimenters were to find neurological activity in the visual pathways before any sight of the object being looked at was reported by the subject, and concluded that it’s a myth that we see things: things are seen not by us but by the cells in our visual cortex.

Or, as Louis Jordan might have said, “Ain’t nobody here but us neurons”.