Cerebrum Macrostructure Flashcards
So at week 7 ish or so, we started out as a as a tube. It’s bending in on itself. Once it started to bend in on itself, we have neurulation happening with the radial processes that are coming out. And we have cells that are traveling from the ventricular zone up into that cortical region to become the ____ as we know it. And we keep getting differentiation until this is about week 28.
cortex
The neural tube stays hollow through development until we have a fully formed ____.
brain
Within the center of the cerebrum we still have a hollowed out space that extends down into the _______ coming down into the medulla. Keep that in mind because that is an important structure for brain function, support, and structural support and integrity.
cerebellum
Look at the cortex at 9 months, the fetus is ready for birth. The cortex starts to have some folds in it, and there were no folds before. It does not stop. The cortex continues to look different. There is a good bit of change from the teenage cerebrum to the adult cerebrum. There is still this development of the cortex that continues to happen through full maturity. Neural development does not stop at birth. It continues on and it’s going to be our (gender/experiences) that shape that.
experiences
Each lobe of the brain is named for the (muscles/bones) of the skull overlying them
bones
One of the defining features of the cerebrum, or the cortex, are the folds and valleys that we have within the brain. The high point is the (gyrus/sulcus) and then as we go in the valley that we have, that is referred to as a (gyrus/sulcus). For the picture on the left, the gyrus is in (blue/pink) and the sulcus is in (blue/pink).
gyrus; sulcus; blue; pink
As the brain folds in on itself, you are taking the structure and are adding surface area to it. The more folds you have in the cortex is (less/more) processing power. So the more complex an organism gets the (less/more) folds we have in the cerebral structure.
more; more
The _____ comes down the middle of the brain and separates the left and right hemispheres of the brain.
longitudinal cerebral fissure
Specific parts of the brain are centered primarily on the left and right side.
The left side (hemisphere) is responsible for (language/spatial awareness). The right side is for (language/spatial awareness) and where I am and what I am doing.
language; spatial awareness
If someone has a stroke on the (right/left) side they’ll have speech deficits, if they have it on the (right/left) side they’ll be bumping into things or even people simply due to the difference in left and right sides of the brain.
left; right
The rat doesn’t have a well defined cortical shell. If you are prey you are constantly under stress because you don’t want to be eaten. There is a lot of stress that is impacted upon the rat. It is that level of (stress/safety) that impacts cortical development.
stress
(Genetics/Epigenetics) refers to biological mechanisms and external factors that have an impact on genetic expression. We see this in human beings who have chronic pain. If an individual has chronic levels of stress from when they were young to an adult they will have cortical changes and behavioral changes. Growing up in stress like poverty has an impact on the cortical development
Epigenetics
As you continue into adulthood, look out how much (less/more) of the enfoldings there are . Chronic stress and childhood trauma impacts what you see at the cortical level.
more
The different areas of the brain have different functions. What three things are the frontal lobe responsible for?
Cognition, motor control, and personality
What two things are the parietal lobe responsible for?
Cognition and sensory perception
What two things are the occipital lobe responsible for?
Cognition and vision
(Cognition/Vision) is present for a majority of the neural structures but there are differences based on the lobe that it sits on – ie. (Cognition/Vision) about what we’re seeing; (cognition/vision) about sensory perception and what to do it; (cognition/vision) designed around movement coordination or personality
cognition; cognition; cognition; cognition
There is a big sulcus that runs down the center of the brain called the ________ sulcus and it separates the precentral gyrus and the postcentral gyrus.
central
The precentral gyrus is (in front/behind) of the central sulcus. And then we have the postcentral gyrus because it sits (in front of/behind) that central sulcus. Those have two key inputs for physical therapist in anybody related with movement coordination, because the precentral is the primary (motor/sensory) cortex. And the postcentral gyrus, is the primary (motor/sensory) cortex.
in front; behind; motor; sensory
What three things are the temporal lobe responsible for?
Hearing, language recognition, and memory processing
If we split the brain in half, on the inner area of the brain you have the (temporal lobe/limbic system).
limbic system
What two things are the limbic system responsible for?
Emotion and memory processing
The (cerebral/limbic) system is an area that is becoming more and more important in PT because the majority of us will be in outpatient practice and will be dealing with individuals with chronic stress/pain situations. The (cerebral/limbic) system plays a role in the emotional aspect that could be making the situation linger in terms of the chronic side of things.
limbic; limbic
The ______ gyrus is where the majority of the emotions are processed and is the primary structure of the limbic system/lobe.
cingulate
The (gyrus/sulci) are what separates the lobes of the brain.
sulci
The ____ sulcus separates the frontal lobe from the temporal lobe.
lateral
The ____ sulcus separates the frontal and parietal lobe.
central
The ____ sulcus separates the parietal lobe from the occipital lobe.
parietooccipital
The _______ is responsible for connecting the right and left hemispheres together to ensure both sides of the brain can communicate and send signals to each other.
corpus callosum
The brain itself is very (soft/firm) and has a (soft/firm) texture to it, it is kind of like firm jello, it is not a (soft/firm) structure so you need to protect it.
soft; soft; firm
Through development there has been a vast network to protect the brain. There are three layers of protection. The outer layer is the ____ mater, then it goes _____, then _____.
dura; arachnoid; pia
The _______ mater really does just look like a spiderweb, it peels off fairly easily off the pia mater. And it’s a very lacy structure, very intricately woven structure. And some say that might be the most important aspect of neural protection.
arachnoid
The ____ mater is very intimate with the brain and very closely adhered to the brain.
pia
The epidural space is a (real/potential) space between the brain and skull. In real life there isn’t a space between the skull and dura mater. If you have trauma to the area like a TBI you can have the epidural space form.
potential
In the spinal cord the epidural space is a (real/potential) space .
real
Once we peel the arachnoid mater away, this is what we have, the cerebrum covered in the ___ mater. And without fixing the brain and making it stiffer, it is virtually impossible to split the ___ mater from the cortical shell without damage to the area.
pia; pia
The meninges come down very intimately to the (lateral/central) sulcus and it just leaves that open space which is where the corpus callosum goes. The brain is covered in dura until we get to the inner edge of the sulcus.
central
The tentorium cerebelli separates the _____, the top part of the brain, to the bottom part of the brain, the _____.
cerebrum; cerebellum
The arachnoid mater is very important because it is trying to (increase/decrease) the surface area that absorbs stress so that you can reduce any sort of impact that happens within the brain itself. This is critical for protection of the brain.
increase
As far as the arachnoid mater itself. There are _____ arrays that are designed. They are a 90 degree oriented structures. When you orient things in 90 degrees perpendicular to each other, you can take something that is fairly flimsy but enhance the structural integrity of it. The structural integrity allows for the flotation of the brain within the skull vault.
trabecular
Embedded within the arachnoid mater are blood vessels that are important in infusing the brain with its blood for transportation of oxygen and nutrients in the ___ and for the preservation of the ___.
CSF; CSF
At the ventricular stage before the cerebrum is formed, we are developing a pia layer that starts at (neogenesis/corticogenesis) and that develops into (arachnoid/pia) mater to protect the brain.
corticogenesis; pia
The most common cause of a meningeal hemorrhage is what?
Head trauma
An (epidural/extradural / subdural) hemorrhage is between the bone and (arachnoid/dura), is typically arterial blood, and is associated with an evolving hematoma.
epi/extradural; dura
A (epi/extradural / subdural) hemorrhage is between the dura and the (arachnoid/dura), is typically venous blood, and is associated with an evolving hematoma.
subdural; arachnoid
So if you’ve had some sort of an insult to the head. It may or may not result in fracture of the skull. But what you have is blood that continues to pump into the skull vault because the arteries and the vessels have been interfered with in some way. So because of that, you’ve got this closed hard shell on the outside and the soft gooey thing on the inside and you keep pumping blood into that area. What’s eventually going to happen is the blood continues to pull. The bubble keeps getting bigger and bigger and bigger. And eventually, it’s going to be a life-threatening situation. This is called an _______ hematoma.
evolving
A (subdural/subarachnoid) hemorrhage is also caused by trauma but also strokes and aneurysms as well.
subarachnoid
The ____ is very important for cushioning and buoyancy for the brain and the transportation for chemical communication (different cell preserving nutrients are coming in and out).
CSF
We have _ ventricles within the CNS, within the cerebrum.
4
There are _ lateral ventricles originating from the telencephalon (don’t need to know where they come from). The lateral ventricle is separated into three horns which are _____, ______, and _____ and they are going to take up the space of all four lobes.
anterior, posterior, and inferior
The cerebral aqueduct is going to participate in communication with the ___.
CSF
The ____ canal continues down into the spinal cord region.
central
The inside of the ventricles are lined by specialized cells called _____ cells. And the purpose of the _____ cells are to take the blood supply, start to filter parts out so that what you’re left with is a clear fluid that we’re going to refer to as cerebral spinal fluid.
ependymal; ependymal
The ependymal cells allow for fluid exchange between the (horns/ventricles) and the (brain/spinal cord) and play a role in electrolyte transport between the (FSC/CSF) and (CNS/PNS), they filter large particles, and line the ventricles and central canal.
ventricles; brain; CSF; CNS
The ventricles are where the ___ is made and majority of them are contained in the ______ space, not within the ventricles. The majority of the _____ is going to be communicated out from the ventricles into the _____ space where it actually can start to do some good.
CSF; subarachnoid; CSF; subarachnoid
The spinal canal comes down and beats ____ into the spinal cord.
CSF
In between the left and right ventricles is the _____ foramen and the purpose of that is to connect the left and right ventricles
interventricular
If we cut the brain, you can see that the lateral ventricle sits (above/underneath) the corpus callosum.
underneath
The medulla oblongota becomes the _____ canal to continue down to communicate ___ into the spinal cord.
central; CSF
As far as the creation of CSF. There is a specific structure called the _____ epithelium, made up of ependymal cells. And the purpose of the choroid epithelium is to start producing ____.
choroid; CSF
Steps in creation of CSF: Step (1/2) - Fluid and matter diffuses out of capillaries
1
Steps in creation of CSF: Step (1/2) - Tight junction between the cells of the choroid keeps large materials out. It is similar to plasma, but lacks the proteins seen in plasma, due to tight junction.
2
Steps in creation of CSF: Step (2/3) - CSF: higher [Mg] and [Cl], lower (K+] and [Ca] compared to plasma. Active transport from capillaries by epithelium produces CSF. It is NOT a passive diffusion. NOT an Ultrafiltrate of plasma.
3
CSF (is/is not) an ultrafiltrate of plasma. And what these epithelium do is they supplement the plasma with magnesium and chloride and take out some potassium and calcium. It’s an active transportation process because even within the plasma, some things are being filtered out and some things are being added in. The reason this is becoming important that now we’re starting to see that in some neurologic conditions where there is damage to the brain, such as a stroke or traumatic head injuries. There is damage to this choroid epithelial process and also some disease conditions. And when you have damage to this area, this _______ balance starts to get thrown off. And that can delay healing or continue to preserve impairments that the individual has because they can’t recover because the ______ balance is off.
is not; electrolyte; electrolyte
Potassium chloride and calcium are critical for preservation of the ____ potential and continuing the _____ potential.
action; action
The choroid epithelium is concentrated within the choroid _____. The choroid _____ is responsible for producing the majority of ____.
plexus; plexus; CSF
This is the flow of CSF: (1/2) - Lateral ventricles, through interventricular foramen into third ventricle.
(1/2) - Third ventricle through cerebral aqueduct (midbrain) into the 4th ventricle. From the 4th ventricle: to meningeal space via foramen of Luschka and to the spinal canal via foramen of Magendie. Absorbed by arachnoid villi.
1; 2
The foramen of Luschka is where the CSF is going to exit the ventricles into the _____ space. And then the foramen Magendie, continues down into the spinal cord to provide ___ to those spinal regions.
subarachnoid; CSF
The CSF is going to be lending nutrients to cellular structures. It’s going to be taking back waste products from the cellular structures. They’re going to be reabsorbed by structures that we call the ____ villi.
arachnoid
If there’s a blockage at the third ventricle or the cerebral aqueduct or somewhere in the spinal canal, or if the arachnoid villi aren’t working properly to reabsorb this fluid back, you are going to get a backup of CSF within the ventricles. And the ventricles are going to start (enlarging/minimizing) and it’s gonna be taking that brain mass and pushing it against the hard skull vault. And not very conducive to life as we know it.
enlarging
(Obstructive/internal, non-communicating / communicating/external) hydrocephalus is impaired CSF flow within the ventricular system. The CSF does not communicate with the subarachnoid space.
Obstructive/internal, non-communicating
(Obstructive/internal, non-communicating / communicating/external) hydrocephalus is obstructive and associated with tumors, TBIs (swelling secondary to internal bleeding), and hemorrhagic strokes (swelling secondary to clot formation).
Obstructive/internal, non-communicating
It’s non communicating hydrocephalus because there’s something happening within the cerebrum and the inner workings that’s blocking the ___ from flowing down either from the lateral ventricle into the third or from the third into the fourth ventricle. So because there’s a blockage there, the ventricles just keep (expanding/minimizing).
CSF; expanding
(Obstructive/internal, non-communicating / communicating/external) hydrocephalus occurs after the CSF gets into the subarachnoid space. There will be blockage of CSF flow through the subarachnoid space & into the venous system. This can lead to a subarachnoid hemorrhage (red blood cells block passageof CSF through thearachnoid villi), birth defects (born with too few arachnoid villi), and CNS infection.
communicating/external
In a communicating hydrocephalus the ventricles are fine and they are able to communicate fluid between each other. They’re able to take that fluid and bring it out into the subarachnoid space. The problem is, there’s an issue with absorption. And that’s happening usually because of an _____ villi dysfunction. And so this fluid can’t be absorbed back into the venous system.
arachnoid
(Communicating/External / Normal pressure) hydrocephalus is episodic CSF pressure elevation that comes on quickly and typically affects the elderly. There is no known cause and the diagnostic features are that of decreased cognition (forgetfulness, decreased attention span), incontinence (urinary and fecal), and gait impairments (apraxia - wide base of support gait).
Normal pressure
So the reason it’s called normal pressure hydrocephalus is like 90 percent of the time, the pressure within the ventricles are normal. And this person’s going through life A okay. And every once in awhile there’s this episodic (increase/decrease) in pressure within the ventricles. Nobody knows why it happens. It typically happens to elderly individuals. We don’t know why it happens. But the three diagnostic features are there, wet wonky and wobbly. So they’re just a little bit off. They’re not acting like themselves. The 3 diagnostic features happen (frequently/episodically).
increase; episodically
