Anatomy Flashcards
What is a gyrus?
A ridge on the cerebral cortex
What is a sulcus?
A depression or furrow in the cerebral cortex
What lobe is Broca’s area in?
Frontal lobe
What lobe is Wernicke’s area in?
Temporal lobe
What does Broca’s area do?
Speech production
What does Wernicke’s area?
Understanding speech
Usage of correct words to express thoughts
What happens if there is a stroke affecting Broca’s area?
Expressive aphasia
Loss of ability to produce language, spoken or written
Patients know something is wrong and get frustrated
What happens if there is a stroke affecting Wernicke’s area?
Receptive aphasia
Inability to understand language, spoken or written
Cannot use words to express thoughts
Patients are unaware of the problem
Where is the primary motor cortex?
On the pre-central gyrus
Where is the sensory cortex
On the post-central gyrus
Where is the primary motor cortex?
Posterior portion of the frontal lobe
Where is the sensory cortex
Anterior portion of the parietal lobe
What does the primary motor cortex do?
Generates neural impulses that control execution of movement.
What does the sensory cortex do?
Receives and interprets most of the human sense of touch.
What side of the brain controls the left side of the body?
Right
Broca’s and Wernicke’s area is in the left side of the brain in….
95% of right-handed people
70% of left handed people
What is the function of the ventricles?
Production and circulation cerebrospinal fluid
Name the four ventricles.
Lateral ventricles X2
Third ventricle
Fourth ventricle
Are the ventricles interconnected?
Yes! There are several foramina - openings acting as channels that connect the ventricles
What is inside a ventricle?
A region of choroid plexus - which is a network of ependymal cells involved in CSF production
What are ependymal cells?
Type of glial cell
Ciliated simple columnar epithelium
They line the CSF filled ventricles in the brain and central spinal canal of the spinal cord
What is special about the apical surface of ependymal cells?
Covered in microvilli that absorb CSF
What do the intraventricular foramina/foramina of Monro connect?
Lateral ventricles to 3rd ventricle
What does the cerebral aqueduct connect?
3rd ventricle to 4th ventricle
What does the median aperture connect?
4th ventricle to subarachnoid space (via cisterna magna)
What do the right and left lateral aperture connect?
4th ventricle to subarachnoid space (via cistern of great cerebral vein)
Describe the flow of CSF.
Lateral ventricles > foramina of Monro > 3rd ventricle > cerebral aqueduct > 4th ventricle > central canal of spinal cord or cisterns of subarachnoid space
How is the choroid plexus formed?
Invagination of vascular pia mater into the ventricular lumen. It becomes highly convoluted and looks sponge-like.
How does the choroid plexus get to each ventricle?
3rd & 4th: through their roofs
Lateral: through choroid fissure
How exactly is CSF produced?
From arterial blood by the choroid plexuses of lateral and 4th ventricle
What is in CSF?
Protein, urea, glucose, salts
Where is CSF reabsorbed?
Into the venous system by passing into the Dural venous sinuses.
The sinus walls have arachnoid villi which aid absorption.
Where is the grey and white matter in the brain?
Grey on outside
White on inside
Where is the grey and white matter in the spinal cord?
Grey on inside
White on outside
What is the corpus callosum?
A thick band of nerve fibres dividing cerebrum into right and left hemispheres. It transfers motor, sensory and cognitive info between the hemispheres
How does the 4th ventricle communicate with the Subarachnoid space?
Via the median foramen or Magendie and lateral foramen of Luschka.
Name the layers of the meninges from inside out,
Pia
Arachnoid
Dura
PAD out
What is the structure of the dura mater?
Fibrous sheet - collagen and elastin
2 layers: outer endostal and inner meningeal
Infoldings contain sinuses
Innervated (can cause headaches)
What is the structure of the arachnoid mater?
Loose connective tissue - collagen, elastin, reticulin
Loosely encloses brain
Where it spans gyri it forms arachnoid and pia cisterns
Space above = subdural space
Space below = subarachnoid space
What is the arachnoid mater’s importance in reabsorption of CSF?
Venous drainage occurs via ‘tufts’ of arachnoid mater - villi - which are mostly in superior sagittal sinus
What is the structure of the pia mater?
Closely adherent to underlying nervous tissue
2 layers:
Pia glia - astrocyte end feet covered by basement membrane
Pia arachnoid - outer layer, connective tissue
Separated from arachnoid by subarachnoid space with fine trabeculae (small rods)spanning between
What is a choroid plexus?
A network of blood vessels in each ventricle of the brain that produces CSF
Name the parts of the corpus callosum from anterior to posterior.
Rostrum, Genu, Body, Splenium
