The “stream/train/flow of consciousness” refers to the notion that consciousness flows like a stream and that things we are aware of fall into our stream and things that we are unaware of lie outside our stream of consciousness. The previous posts dealing with stuff like blindsight and electrical stimulations of the somatosensory cortex are inconsistent with the idea of a stream of consciousness. But let us look at it more in depth.
What is consciousness? The description of consciousness is very similar to that of attention (with the difference that attention is a bit more open to scientific investigation). Attention has been defined as a cognitive process that chooses to allocate more resources to some tasks (those considered more important) while allocating less resources to other (less important) tasks. This begs the question, who/what is doing the prioritisation? It seems to be the case that attention is not indivisible or serial as different processes or stimuli can direct attention presumably at the same time. This leads us to ask, assuming that consciousness actually exist and has some effects on our physical body, what are these effects? What does consciousness do? Assuming that brain activity scans, show no difference between driving “consciously” (as in paying attention to your surroundings) and “uncounsciously” (immersed in your thoughts and not paying attention to your surroundings), what is then the physical manifestation of consciousness (assuming that “consciousness” exists)?
One important bit about our own accounts of consciousness is that they seem to talk about a single thing or stream where everything comes together, while on the other hand, attention is a divisible and presumably parallel system with no central executive system or core.