Ah but what if it's a cascading effect?
  Snowball starts rolling from the visual cortex, the dominoes
  fall and by the time it reaches conscious processing, we're
  already 1/2 way there tongue emoticon

  Anyway, the issue of Attention is a very important one with
  regards to decision-making. We ignore nearly everything around
  us nearly all of the time (which is something that was always a
  struggle for me - I suspect I'm in the autistic spectrum
  somewhere) ... and I suspect we'll find decision-making
  happening all throughout our bodies.