In the previous post on control consciousness, I presented a case in favor of non-sensory control phenomenology. Despite these considerations in favor of thinking that control infects large portions of our phenomenology, there is something tempting about the claim that there is no non-sensory control phenomenology. If a theory does not credit such a temptation as leading to the truth, then it would be a virtue of the theory if it could explain why such a temptation exists any way. I will here briefly sketch two main ways in which the temptation may be accounted for. The first concerns the differential bandwidth between prototypical instances of sensory inputs and motor outputs. The second concerns the degree to which introspection is itself an act.
Sensory inputs may be compared with each other and with motor outputs in terms of bandwidth. Estimates of the bandwidth of the human eye for color vision range from 4.32 x 10^7 bits/sec (Jacobson, 1950, 1951) to a more recent estimate of 10^6 bits/sec (Koch et al., 2006) aka a megabyte per second (1MB/sec). It is perhaps not surprising that hearing has a significantly lower bandwidth than vision (a picture being worth a thousand words, and all). Jacobson (1950, 1951) gives an estimate of 9,900 bits/sec for the bandwidth of the human ear. He also gives a bandwidth estimate of 4.32 x 10^6 bits/sec for the eye for black and white vision. These differences in bandwidth perhaps account for widespread intuitions such as the intuition that visual “qualia” are ineffable, the intuition that a person blind from birth can never be told what its like to see (Hume, Locke), and the intuition that a person reared in a black and white environment wouldn’t know what its like to see red (Jackson, 1982). The auditory channel is relatively impoverished compared to the visual channel, and the black and white visual channel relatively impoverished compared to the color channel.
So what happens when we turn our attention to motor systems? Bandwidth estimates for motor output systems are far lower than either vision or hearing. Fitts (1992) estimates motor output bandwidth at 10 to 12 bits/sec. I offer that bandwidth differences between various sensory systems and output systems can serve as a basis for explaining why many may have the intuition that there is no distinctive phenomenology for control consciousness.
Introspection as Mental Action.
Another explanation of why some may have supposed that there is no control phenomenology, an explanation that may work together with the bandwidth-based explanation, hinges on the fact that introspecting is itself an act. As such, it is reasonable to suppose that a greater load is presented in introspecting control consciousness than in introspecting sensory consciousness. To spell this out further, let us assume, for purposes of illustration, that motor systems and sensory systems have the same bandwidth. If so, bandwidth alone would not serve to account for an apparent difference in phenomenological richness. If, however, there were some additional factor present that inhibited the ability to introspectively attend to motor systems but not sensory systems, then that factor would serve to explain a difference in apparent richness.
What could such a factor be? It is a relatively well known that attempting simultaneous multiple control tasks diminishes the capacity one would otherwise have to do them singly. If introspection is itself an act, then introspecting motor control is a doubling of tasks in a way that introspecting otherwise passive sensory input is not. The doubling introduced in introspecting control consciousness thus serves as the sought-after factor that can explain a comparative lack of richness between control and sensory systems.
1. Control Consciousness
2. The Pure Perceptual Model
3. The Motor Theory
4. The Imagery Theory
5. Introducing AEI
6. Control Consciousness Explained
7. Libet’s Puzzle of Will
8. Control Phenomenology