I don’t think that it is controversial to say that the brain has a variety of structures that interact to form general intelligence. As has been pointed out elsewhere in this forum, several types of memory exist, and while the cortex seems to have much the same structure over the entire sheet, many types of processing nodes can be found in the subcortical structures.
It seems to me that the subcortical structures orient the processing fabric of the cortex to access memory to learn and to solve problems.
What we call consciousness is the subjective experience of having the subcortex push and prod the cortex to experience the world via “attention” and chains of selective recall. In William James " The Principles of Psychology" in 1918 he describes this chaining of conscious attention. See figures 41, 42, and 43. Please consider the James text as describing the evolution of the contents of the “global workspace” model; in particular, the “Dehaene–Changeux model” implementation.
This direction of attention to search solution spaces by navigating higher dimension manifolds of information is a big part of how General Intelligence works and you will have to emulate what the subcortex does if you have any hope of creating AGI.
I am working to understand what mechanisms the subcortex uses to perform these tasks. Yes, the big cortex (HTM/TBT) does the heavy lifting but the subcortex does the driving.