In seems that we are conscious of an event a fraction of a second after our brains start to process the perception of the event. This is not surprising we are conscious of the finished perception and finishing the perception takes time. The surprise is that we live in the present and not a fraction of a second into the past. How is this done?
There seems to be three possibilities:
- we live a fraction of a second into the past but never realize it.
- we play very weird games with the perception of time and simultaneous events.
- we do not live in the past but in a projection of the past into the future, giving an approximate present.
The last one seems the most useful to us and also may be a good reason to have consciousness. If the present is t0 and at that time the brain is constructing a model of the world as of t-x. This model is then run forward as a simulation through x duration of time so that it represents a simulation of t0. So we would be living in a simulation of the present. This gives a measure of error to prompt corrections of motor action and of perception. That would really be a cool system and well worth the effort of creating a single global model of the world accessible by all the systems of the brain.
It is not take much of a leap to go from thinking of a MPOFBL system (massively parallel overlapping feed-back loops) to thinking of a MPOFFL system (massively parallel overlapping feed-forward loops).
After writing the above but before posting it, I found a blog post on a NYTimes article. See article and blog. They discuss visual illusions that point to a projection into the near future. In particular the article talks about seeing an image before it actually happens.
In an experiment originated by Dr. Nijhawan, people watch an object pass a flashbulb. The timing is exact: the bulb flashes precisely as the object passes. But people perceive that the object has moved past the bulb before it flashes. Scientists argue that the brain has evolved to see a split second into the future when it perceives motion. Because it takes the brain at least a tenth of a second to model visual information, it is working with old information. By modeling the future during movement, it is seeing the present.