I knew you were going to say that...

...I just scanned your brain.

A study recently published in Nature Neuroscience and reported at Wired.com states that researches could predict simple decisions made by people seven seconds before they were consciously aware of their own decision.

The participants in the study had to make a decision whether to press a button with their left or right hand.

"In the seven seconds before Haynes' test subjects chose to push a button, activity shifted in their frontopolar cortex, a brain region associated with high-level planning. Soon afterwards, activity moved to the parietal cortex, a region of sensory integration. Haynes' team monitored these shifting neural patterns using a functional MRI machine.

Taken together, the patterns consistently predicted whether test subjects eventually pushed a button with their left or right hand -- a choice that, to them, felt like the outcome of conscious deliberation. For those accustomed to thinking of themselves as having free will, the implications are far more unsettling than learning about the physiological basis of other brain functions"

The implications being that free will might be an illusion.

I'd personally see it more of a computer analogy. A simple computer diagram would be input(plus instructions)->processing->output. I would argue that after input and instructions, we don't consciously come to a decision until the output stage, with our subconscious taking care of the processing part and our conscious mind converting the electrical impulses back to understandable thoughts.

I'm thinking of data+instructions: Right or Left plus data from the task.

Processing: Data and instructions are now electrical impulses in the brain, being processed.

Output: Electrical impulses carrying the "result" back are brought translated back into conscious thought.

I would guess the researchers in this case are like a computer being able to read binary before it's converted into output.