Talk:Paleocortex

Contradiction on phylogenetic age
At the start of the introduction it is stated that paleocortex is phylogenetically older than archicortex. At the end of the introduction the opposite is stated. Please correct. — Preceding unsigned comment added by 145.109.82.34 (talk) 14:06, 13 July 2020 (UTC)

Phylogenetic age
Paleocortex is not proven to be "intermediate phylogenetically between the neocortex and archicortex". Some authors believe that paleo- and archicortex are seperate phylogenetic entities, and that these cortices contribute to the "dual origin of the cerebral cortices" (or neocortex) (Pandya and Barnes in The Frontal Lobes Revisited, Ed. Ellen Perecman, 1987).

3-5 laminae
Hi all,

First, a big thank you to Rob Hurt for updating and improving the definition. The only comment I have is that the correct range for the number of laminae in the paleocortex actually is 3-5. In fact, it usually has 3 layers. Purves is very confusing in the way it presents this info. In the 4th edition, the info that paleocortex typically has 3 layers is on page 666, while more general info (that it has fewer laminae than neocortex) is presented on page 831. To make matters worse, they write that archicortex has "even fewer laminae", rather than "sometimes fewer laminae," than paleocortex. Then things get even more complicated when (back to p.666), Purves notes that the hippocampal cortex has 3-4 layers and comments that it is comprised of archicortex. So now we have info that archicortex sometimes consists of 4 layers, after which Purves writes that paleocortex is probably more primitive than archicortex, the opposite of what you would expect if you went by their info on p. 831 (neocortex has greatest number of laminae, then paleocortex, then archicortex).

Why they organized it like this is beyond me!

Anyway, normally I would just make the relevant changes, but I've noticed that you're operating from the 5th edition while I've got the 4th. Is this information updated or written more clearly in the 5th? In particular, is there an analogous info box to the one on p.666 of the 4th? The one in the 4th is box 26A and is at the beginning of chapter 26, The Association Cortices, if that helps at all. I would be happy to just make the edit if you'd prefer, but I'm very curious to see if they've updated this info.

Firecatalta (talk) 21:23, 27 August 2013 (UTC)

Hi Firecatalta,

Sorry for taking so long to get back to you.

In the fifth edition, Purves writes: "Another, presumably even more primitive, type of cortex is the paleocortex (paleo, "ancient"); paleocortex generally has three layers and is found on the ventral surface of the cerebral hemispheres and along the parahippocampal gyrus in the medial temporal lobe." (p. 590)

However, on page 731, there is a comment that implies that paleocortex has more than three layers.

It's up to you on how you want to handle the info here.

Hope that helps. Rob Hurt (talk) 23:36, 16 December 2013 (UTC)

Merge proposal
Suggest merging paleocortex with allocortex. This is a stub which is a subtopic of allocortex and information would be more helpful on one page. Iztwoz (talk) 11:54, 5 May 2014 (UTC)