Cortical grid cells and Abstract ideas


A point to consider regarding the Hippocampus and Entorhinal cortex: It is common to attribute spatial processing to this area. The discovery of place and grid cells has biased many to think that this is where this sort of representation is processed.

It is tempting to think that the cognitive map resides there.

I suggest that you take a more nuanced view of the relationship of these areas and spatial processing.

Patient HM continued to have the cognitive ability to process spatial concepts even though he had lost the ability to form new memories. You would think that the loss of the “cognitive map processor” or “spatial processor” would cripple these capabilities if this were true.

We should note that H.M. did particularly well on such timed tasks as the Block-Design subtest of the Wechsler Scale, or Milner’s version of Hebb’s triangular-blocks task (HEBB [8], p. 278 ; MILNER [14]). His success on these tests clearly indicates that spatial relationships as such cause him little trouble.
See some of the details here:

I offer that this has been an area where this representation has been observed but the rest of the cortex is also processing the same information. As I have posted elsewhere in this forum (here and here), I think that the HC/EC complex is important for short term (~one day) storage of this information. I also think that this is where experience interacts with emotional coloring from the amygdala to form valuation of objects and events.

The general spatial processing task is performed in the cortex, likely distributed over the temporal and parietal lobes.