Some of you know, from various conversations, that over the last year or so I’ve flirted with the idea that consciousness is metacognition, although I’ve gradually backed away from it. In humans, we typically define mental activity that we can introspect to be conscious and anything else to be unconscious. But I’m swayed by the argument that mental activity accessible to introspection, but that we never get around to actually introspecting, is nevertheless conscious activity.
I had thought the idea of consciousness being metacognition was essentially what HOT (high order theories) of consciousness were all about, and so my backing away from the metacognition idea seemed to entail backing away from HOT. However, a recent paper written to clear up common misconceptions about HOT points out that this is mistaken (page 5).
Just to review: metacognition is cognition about cognition, thinking about thinking, awareness of our own awareness, etc. It’s essentially introspection and is necessary for introspective self awareness.
HOT, on the other hand, posits that there are two types of mental representations. There are simple representations about the external world, such as the neural pattern that forms in the visual cortex based on signals from the retina. This would be a first order representation. First order representations are often associated with early sensory processing regions and are not themselves sufficient for us to be conscious of them.
Then there are representations about these first order representations. These are second order, or higher order representations, and are often associated with the prefrontal cortex, the executive center of the brain.
Under HOT, the contents of consciousness are these higher order representations. The higher order representation is us being aware, conscious, of the first order representation. (To be conscious of the higher order representation itself requires another higher order representation.) Our sense of inner awareness comes from these representations of the representations.
Given that I’ve often pondered that qualia are the raw stuff of the communication from the perceiving parts of the brain (where the first order representations are) to the planning parts of the brain (where the second order representations are), HOT strikes me as very plausible.
Crucially, higher order representations, despite their name, are much more primal in nature than metacognition. The paper does admit that they likely share some common functional areas, but metacognition is a more sophisticated and comprehensive activity. It strikes me as very likely that metacognition is built with recursive higher order representations.
My only reservation with HOT, and I’m sure various specific versions handle this, is that not just any higher order representation is going to be conscious. It will depend on where in the information flows that representation is formed. That and the higher order representation shouldn’t be thought of a simple echo of the first order one, but as informational structures which have their own unique functionality.
Ultimately HOT will have to be judged by how well it matches observations, but a nice implication of it is that inner experiences aren’t ruled out for species that show little or no evidence for metacognition.