Tuesday 11 October 2011

Free to do what I want! …or not?

You’re standing in a department store and you’re shopping for clothes. There’s a big selection. Eventually you choose a new pair of Levi jeans, you had a lot of choice though.

Or did you?

What if the choices that you think you make have actually been made for you, several seconds before by your brain? What if, in fact, you had no Free Will?

Free Will is a big philosophical question, with passionate arguments on either side. Most people would assert that in their everyday lives they experience free will as they choose what they eat, who they talk to, how to get to work and what glass of wine they will have with dinner. But as our knowledge of how the brain works expands, Neuroscience may be slowly shattering the idea that we have control over our own lives.

A study done by Haynes and his group at the Bernstein Centre for Computational Neuroscience in Berlin has posed some challenging questions on this subject. Subjects were placed in an fMRI machine (a type of brain scanner that measures brain activity by tracking minute changes in blood flow) and shown a series of random letters. They were told to press a button in front of them whenever they felt like it, with either their left or right hand and to remember which letter was shown when they did.

Looking at the brain activity of subjects, Haynes was able to see that the conscious decision to press the button was made a second before the act, which seems reasonable. But he also found a pattern of brain activity that preceded the decision by as much as seven seconds. It seems that before the subjects were aware they had made a choice, their brains had made it for them.

These seem rather unsettling findings. The idea that our brains are making all our decisions for us is not a pleasing one. There have been other experiments such as this but it is too early to say that Neuroscience has killed our notion of free will. Future experiments will have to establish fully that these early pattern of brain activity really do result in unconscious decisions, rather than simply being part of a wider parallel decision making processes. Future studies will also need to apply simple lab tests to the complex decisions we make in real life.

Neuroscience hasn’t set out to destroy our long (and proudly) held view that as humans free will makes us special. But it is certainly asking some fascinating questions. 

link to paper via Nature Neuroscience: