Tuesday, April 15, 2008

Tyranny of the Unconscious

According to a report in the journal Nature, researchers have found that your brain makes up its mind up to ten seconds before you realize it. By scanning brain activity while decisions are being made, the researchers were able to predict what choice people would make even before they themselves were even aware of having made a decision. The work calls into question the "consciousness" of our decisions and may even challenge ideas about how "free" we are to make a choice at a particular point in time.

“We think our decisions are conscious, but these data show that consciousness is just the tip of the iceberg,” said Dr. John-Dylan Haynes, a neuroscientist at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany.

Dr. Haynes and his colleagues imaged the brains of 14 volunteers while they performed a decision-making task. The volunteers were asked to press one of two buttons whenever they felt the urge. Each button was operated by a different hand. At the same time, a stream of letters were presented on a screen at half-second intervals, and the volunteers were asked to remember which letter was showing when they decided to press their button.

When the researchers analysed the data, the earliest signal the team could pick up started seven seconds before the volunteers reported having made their decision. Because there is a delay of a few seconds in the imaging, this means that the brain activity could have begun as much as ten seconds before the conscious decision.

From this data, the researchers concluded that the unconscious mind already made its decision 7 to 10 seconds before the conscious mind "decided" what to do. What might this mean, then, for the nebulous concept of free will? Since most people's definition of "free will" involves conscious decision making, is there really such a thing as free will if the unconscious mind had already made the decision a priori? If choices really are being made several seconds ahead of awareness, “there’s not much space for free will to operate,” according to Dr. Haynes.

One way to resolve this issue was suggested by the somewhat daft film What The Bleep Do We Know? Looking at data from a different brain-imaging experiment which considered the time between sensation and perception of the sensation, researchers in the film concluded that the brain must use quantum time-reverse symmetry to send a signal back in time. Taking their theory to the recent experiments implies that once the conscious mind has made its decision, it sends a signal back 7 to 10 seconds into the past to tell the unconscious brain how to behave.

Fun to consider but back here on planet Earth, Dr. Frank Tong, a neuroscientist at Vanderbilt University in Nashville, says it is likely that "neuroscience will alter what is meant by free will." Since the participants were consciously aware of their decisions a full 7 seconds after they were made, this suggests a lack of free will. In other words, this implies there is some unconscious (zombie) process that controls the decision making, not the conscious self.

I propose that neuroscience will alter what is meant by the self. Looking at the experiment, I conclude that there is in fact free will as long as the "self" making the decision is not restricted to the conscious mind, but includes the unconscious processes as well. I don't "decide" to produce digestive enzymes, but the gall bladder still leaks them out without my conscious decision. I don't decide to grow my fingernails out, but there they go. Are my gall bladder and fingernails not part of "me" if they're not controlled by my conscious mind? Or are they just things possessed by a separate "ego self?" Or to put it more broadly, am I (the ego self) just my mind consciousness, residing in this body, an entity separate from the self, like a hermit crab residing in a shell? This argument goes all the way back to Descartes' philosophy of mind/body duality. "I think, therefore I am," but am I only what I think?

According to one on-line commenter, the experimental results are not surprising since, among the qualities required for survival and procreation, consciousness is one of the least important. Totally insentient trees and grasses are surviving and reproducing. Many animals get along fine without a brain. Do they lack free will?

1 comment:

GreenSmile said...

Glad to see you back on this channel, Shokai.

I could be accused of reading too little in to it but when I read this account by neuroanatomist of a stroke that she suffered, I found it a fairly clear item of evidence for the assertion that what we experience as our "soul" is really just the din of a shouting match between various concurrent activities in sundry brain regions. Of course, that was an understanding I had already reached based on introspection and observation of others. It always helps to know what you wanted to find before you go looking.