Not to tout this post as a cure for everything but it does describe some of the low level mechanisms of hex-grid coding and the front running theories of how they form. About in the middle it describes how maps can “stack up” or overlay projections to make a form of voting to build up to a peak of activation. This is the same as driving a place cell.
We know from various papers that where high level processed data terminates the data is reversible from the hippocampus. That implies that the cortex state can be recalled to recall a memory representation from the hippocampus to the cortex.