Let us now return to Chalmers' approach but as a physicalist. If we could access qualia directly via the neuronal system, then we could express and articulate them. Because we can't access qualia at all, we could conclude that qualia are independent, or at least partly independent, of the neuronal system. That also means that there must be different levels of how the mind can be accessed; some levels can be accessed via sensory or cognitive processes etc (easy problem) but others not (hard problem). In physicalism, those levels must have a physiological origin, which means that distinguishable physiological systems must exist which correspond to the hard problem or the easy problems.
The existence of such systems or 'levels of consciousness' may also be reflected in the memory system. Computation has a clock rate which should somehow be correlated to the memory systems which is an integral part of computation. The brain is organized from short- to long-term memory, which may work at different space and time scales. Then, they must operate quite differently in identifiable physiological systems.