This part isn’t quite right. Here’s some background if it helps.
Part of your brain is a big sheet of gray matter called “the cortex”. In humans, the sheet gets super-crumpled up in the brain, so much so that it’s easy to forget that it’s a single contiguous sheet in the first place. Also in humans, the sheet gets so big that the outer edges of it wind up curved up underneath the center part, kinda like the top of a cupcake or muffin that overflows its paper wrapper.
(See here if you can’t figure out what I’m talking about with the cupcake.)
The outside bit of the cortical sheet (usually) has 3 visible layers under the microscope, and is called “allocortex”. It consists mostly of the hippocampus & piriform cortex. The center part of the cortical sheet (probably 90%+ of the area in humans) is called “isocortex”, and (usually) has 6 visible layers under the microscope. The term “neocortex” is mostly treated as a synonym of “isocortex”, with “isocortex” more common in the technical literature and “neocortex” more common among non-experts.
The isocortex includes lots of things like “visual cortex” and “somatosensory cortex” and “prefrontal cortex” etc. But despite that, you don’t say “there are many cortices”. Grammatically, it’s kinda like how there’s “Eastern Canada” and “Central Canada” and “Western Canada”, but nobody says that therefore there are “many Canadas”. You can say that visual cortex is “a region of the cortex”, but not “a cortex”.
This part isn’t quite right. Here’s some background if it helps.
Part of your brain is a big sheet of gray matter called “the cortex”. In humans, the sheet gets super-crumpled up in the brain, so much so that it’s easy to forget that it’s a single contiguous sheet in the first place. Also in humans, the sheet gets so big that the outer edges of it wind up curved up underneath the center part, kinda like the top of a cupcake or muffin that overflows its paper wrapper.
(See here if you can’t figure out what I’m talking about with the cupcake.)
The outside bit of the cortical sheet (usually) has 3 visible layers under the microscope, and is called “allocortex”. It consists mostly of the hippocampus & piriform cortex. The center part of the cortical sheet (probably 90%+ of the area in humans) is called “isocortex”, and (usually) has 6 visible layers under the microscope. The term “neocortex” is mostly treated as a synonym of “isocortex”, with “isocortex” more common in the technical literature and “neocortex” more common among non-experts.
The isocortex includes lots of things like “visual cortex” and “somatosensory cortex” and “prefrontal cortex” etc. But despite that, you don’t say “there are many cortices”. Grammatically, it’s kinda like how there’s “Eastern Canada” and “Central Canada” and “Western Canada”, but nobody says that therefore there are “many Canadas”. You can say that visual cortex is “a region of the cortex”, but not “a cortex”.