Perhaps if I were more of visual-spatial learner, I wouldn't find it so hard to create a mental map of all these anatomical terms to describe parts of the brain, but I do have my limitations in that department. It might be related to the fact that I have left-right agnosia. (Etymology of agnosia: the word means "not knowing" from the Greek prefix a- meaning not and gnosis meaning knowledge.)
Anyway, perhaps thanks to my poet/linguist/lexicographer/librarian dad, I do have a natural inclination towards linguistics, so I think that making notes about some of the etymologies will provide helpful mnemonic devices to keep everything straight in my head.
Sulcus is from the Latin for "furrow" (all those wrinkly depressions in your brain are sulci) Large ones that divide your brain into lobes are called "fissures." Technically the fissure that divides your brain into its left and right half is a sulcus, but people don't usually call it that.
Chris had a neat demonstration in class last week where he took a sheet of paper and talked about how you store in the information in it much more compactly if you crumpled it up. That's why we have such wrinkly brains.
The extensiveness of fissures we have in the brain is called gyrification. Gyri is from a Latin word meaning "ridges," but for some reason we haven't talked a lot about gyri, just sulci in class.
Sulcus and gyrus both have strange associations for me. When I see the word "sulcus," I think sulky! And gyrus makes me think of Lewis Carroll's Jabberwocky "slithey toves did gyre and gimbal in the wabe."
I have to wonder about the mathematics of all that "gyrification" or, as it's sometimes called all that "foliation." Why is the brain shaped the way it is? I guess the answer is, because it works! As Chris mentioned, the geometry of the human birth canal is a constraint. Bigger brains makes it hard on the mom!
Higher mammals have more gyrification than lower life forms. Dolphins have a lot! Humans have more than macaques, who have more than rodents.
In humans, gyrification starts midway through pregnancy and continues in the postnatal period.
There are disorders: Pachygyria (broad or "thick" gyri), lissencephaly (smooth brain), and polymicrogyria (multiple small gyri) Among other things such disorders can lead to problems with functioning as well as seizures.
Lobe comes from lobus "hull, husk, pod."
There are four lobes of the brain--all their names come from the names of the bones that cover them. Those bones are sort of bony plates (like continental plates!)
frontal makes obvious sense
temporal not so much, but I can remember it by associating with the "temple" area of your head. But why is that area called "temple" to begin with? The Online Etymology dictionary says the following:
temple (2)
"side of the forehead," early 14c., from O.Fr. temple "side of the forehead" (11c.), from V.L. *tempula (feminine singular), from L. tempora, pl. of tempus (gen. temporis) "side of the forehead," probably originally "the thin stretch of skin at the side of the forehead." Possibly associated with tempus span "timely space (for a mortal blow with a sword)," or from the notion of "stretched, thinnest part," which is the sense of cognate O.E. ðunwange, lit. "thin cheek."
parietal lobe hmm, that's a toughie. Parietals are a word that kids don't know any more. But it used to refer to college dorm rules for the hours during which students could have visitors of the opposite sex. And it sort of sits on the "top rear" of your brain, so I kind of envision the parietal lobe as being like the dormitory proctor (that what they call them in Harvard Yard) or warden (that's what they used to call them at Bryn Mawr when I was a student) in charge of enforcing the rules. The word "parietal" comes from a Latin word meaning walls, and presumably their usage in a college rules context comes from the fact that colleges were originally walled off cloisters from the world. I guess your parietal bone is sort of like a big wall too.
Occipital literally means "back of the head." Occidens means "sunset" or "west" just as "orient" comes from roots that mean dawn or east. So if you are facing east, your occipital lobe is facing west.
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