Researchers using brain scans have shown that decisions are made in the subconscious several seconds before we're even consciously aware of them. Scientists at Berlin's Bernstein Center for Computational Neuroscience used fMRI to watch their subjects' brains as they were asked to tap a button whenever they wanted to. Turns out, the prefrontal cortex lit up seven seconds before the volunteers ever hit the button. They published their research in the scientific journal Nature Neuroscience. From New Scientist:
"It seems that the brain is making the decision before the person themselves," (says neuroscientist John-Dylan Haynes.)
Although we make some choices in a heartbeat, Haynes thinks his experiment captures the dawdling tempo of daily life.
"In most cases, we decide internally in a self-paced way: 'Now I want to get some orange juice' or 'I'm going to get some apple juice instead','" he says
Our brains might pick beverages long before we realise, but Haynes thinks such decisions are still a matter of choice. "My conscious will is consistent with my unconscious will – it's the same process," he says.