1 - Overview of CNS

Question 1

What are the major reflections made by folds of the dura mater and what does each separate?

Answer 1

1. Falx cerebri - between cerebral hemispheres
2. Tentorium cerebelli - between cerebrum and cerebellum
3. Falx cerebelli - between cerebellar hemispheres
4. Diaphragma sellae - covers pituitary

Question 2

What is the outermost meninge? What layers is it composed of?

Answer 2

The dura mater: composed of a periosteal and a meningeal layers.

Question 3

What is located between the periosteal and meningeal layers of the dura mater? Name them.

Answer 3

The dural venous sinuses: superior sagittal, inferior sagittal, straight, transverse, sigmoid, cavernous, superior petrosal, and inferior petrosal.

Question 4

Name the four types of brain herniations?

Answer 4

1. Subfalcine
2. Central
3. Transtentorial
4. Tonsillar

Question 5

What is the location of a subfalcine brain herniation?

Answer 5

Cingulate gyrus under falx cerebri.

Question 6

What is the location of a central brain herniation?

Answer 6

Brainstem towards foramen magnum.

Question 7

What is the location of a transtentorial brain herniation?

Answer 7

Medial temporal lobe through tentorial notch.

Question 8

What is the location of a tonsillar brain herniation?

Answer 8

Cerebellar tonsils through foramen magnum.

Question 9

What is the second layer of meninges? What is in it and what is deep to it?

Answer 9

Arachnoid mater, doe snot dip into sulci and fissures except where it follows falx and tentorium.

CSF in subarachnoid space where blood vessels are located.

Question 10

What are arachnoid villi?

Answer 10

Projections of arachnoid and subarachnoid space that project into dural venous sinuses to reabsorb CSF.

Question 11

What is the deepest meninges layer? Describe it.

Answer 11

The pia mater: faithfully follows brain contours.

Forms perivascular sheath,.

Separates the subarachnoid space from the perivascular spaces (Virchow-Robin spaces).

Question 12

What separates the left and right hemispheres of the cerebrum? What connects these structures?

Answer 12

The Septum pellucidum.

The corpus callosum are nerve fibers that connect the cerebral hemispheres.

Question 13

What are Brodmann’s areas?

Answer 13

Map of cerebral cortex based on the cellular architecture.

Question 14

Define a sulcus, fissure, and gyrus?

Answer 14

Sulcus: groove on surface of the brain

Fissure: deep furrow of cleft

Gyrus: prominent, rounded elevation on the surface of the cerebrum.

Question 15

What fissure separates the cerebral hemispheres?

Answer 15

The sagittal/longitudinal fissure.

Question 16

What does the lateral sulcus/sylvian fissure separate?

Answer 16

The frontal and parietal lobe from the temporal lobe.

Question 17

What does the central sulcus separate?

Answer 17

Located in coronal plane, separates the frontal and parietal lobes.

Question 18

Where is the cingulate sulcus located?

Answer 18

Above the corpus callosum; it curves around and forms the marginal ramus.

Question 19

What is a trick that can be sued to locate the central sulcus?

Answer 19

Trace the cingulate sulcus and jump forward one gyrus to find the central sulcus.

Question 20

Where is the parietooccipital sulcus?

Answer 20

Between the parietal and occipital lobes.

Question 21

Where is the calcarine fissure located?

Answer 21

Within the occipital lobe.

Question 22

What is the function of the frontal lobe?

Answer 22

Higher cognitive functions, control of voluntary movements, and motor area for speech.

Question 23

What are the gyri of the frontal lobe?

Answer 23

Precentral gyrus - the primary motor cortex

Frontal gyri:

1. Superior: premotor and supplementary motor cortex
2. Middle: premotor and supplementary motor cortex
3. Inferior gyrus

Orbital gyri
Gyrus recti

Question 24

What are the parts of inferior gyri of the frontal lobe?

Answer 24

Opercular: left hemispheres = Broca’s area

Triangular: left hemisphere = Broca’s area

Orbital

Question 25

Other than the notable gyri, what is located in the frontal lobe?

Answer 25

The olfactory sulcus and the anterior paracentral lobule.

Question 26

What is the function of the parietal lobe?

Answer 26

Conscious sensation and association cortices. Touch, temperature, pressure, pain, body position (proprioception). Integrates sensory information together.

Question 27

What is in the post central gyrus of the parietal lobe?

Answer 27

The primary sensory cortex and Brodmann's areas 3, 1, and 2.

Question 28

What structures are located in the parietal lobe?

Answer 28

Postcentral sulcus and gyrus, intraperietal sulcus, superior parietal lobule, inferior parietal lobule, precuneus, and posterior paracentral lobule.

Question 29

How would you go about finding the supramarginal gyrus (part of inferior parietal lobe) in the lab?

Answer 29

By following the lateral sylvian fissure back; the supramarginal gyrus caps that lateral fissure at the end.

Question 30

How would you go about finding the angular gyrus (part of the inferior parietal lobe) in lab?

Answer 30

By following the superior temporal gyrus back, it will come to a dead end and the capping gyrus at the end will be the angular gyrus.

Question 31

Where are the supramarginal gyrus and the angular gyrus located? What shape are they?

Answer 31

In the inferior parietal lobe. Both are upside-down horseshoe shaped.

Question 32

What is the function of the temporal lobe?

Answer 32

Comprehension of language. Hearing.

Question 33

What are the gyri of the temporal lobe?

Answer 33

Temporal gyri: - superior - containing the primary auditory cortex (wernicke's area) - middle - inferior Lateral occipitotemporal/fusiform gyrus

Question 34

What is the function of the occipital lobe?

Answer 34

Vision and interpretation of visual images.

Question 35

What are the structures of the occipital lobe?

Answer 35

Preoccipital notch Calcarine fissure Striate cortex: primary visual cortex and Brodmann's area 17 Cuneus Lingual gyrus

Question 36

What are the functions of the limbic lobe?

Answer 36

``` Feel Feed Fight Flight Fornication ```

Question 37

What are some key gyri and sulci of the limbic system?

Answer 37

Cingulate sulcus and gyrus, parahippocampal gyrus, and the uncus.

Question 38

What are two important structures located in the limbic lobe? Where are they located in relation to each other?

Answer 38

The hippocampus and the amygdala. Amygdala is located anterior to the hippocampus (you know you're anterior enough to be looking at the amygdala when the slit near the hippocampus disappears).

Question 39

What is the insula and where is it located?

Answer 39

Structure responsible for taste and integrated pain response. Visible when you pull apart the slylvian fissure.

Question 40

What is the function of the basal ganglia (aka nuclei)?

Answer 40

Precise control of voluntary movement.

Question 41

What are the components of the basal ganglia?

Answer 41

The caudate nucleus: lateral portion of the lateral ventricle Lenticular nuclei: putamen and globus pallidus

Question 42

What is the diencephalon and what are its components?

Answer 42

Middle part of the brain. Thalamus, hypothalamus, epithalamus(pineal gland), subthalamus, and the mamillary bodies.

Question 43

Where is the thalamus located and what is its function?

Answer 43

Third ventricle. Transmits all sensation (except olfaction) to cerebral cortex.

Question 44

What is the function of the hypothalamus and the epithalamus?

Answer 44

Hypothalamus: endocrine and ANS function Epithalamus (pineal gland): plays role in sleep/wake cycle

Question 45

What is the function of the cerebellum?

Answer 45

Process sensory information to regulate movement. Makes movements fluid.

Question 46

What are the components of the cerebellum?

Answer 46

Vermis - "worm-like" Cerebellar hemispheres Cerebellar tonsils - near foramen magnum

Question 47

What is the function of the brainstem?

Answer 47

Homeostasis. Sensory, motor, and ANS innervation of the head and neck.

Question 48

What are the components of the brainstem?

Answer 48

The midbrain, pons, medulla, and cranial nerves.

Question 49

What are the components of the midbrain?

Answer 49

Tectum: superior and inferior colliculi (roof-like) Tegmentum: cerebral peduncles

Question 50

Describe the route that CSF takes through the ventricular system.

Answer 50

1. Lateral ventricles 2. Interventricular foramen of monro 3. Third ventricle 4. Cerebral aqueduct of Sylvius 5. Fourth ventricle: 2 lateral aperatures (forman Luschka) and 1 medial aperature (foramen Magendie) 6. Central canal of spinal cord

Question 51

What structure separates the lateral ventricles?

Answer 51

The Septum pellucidum.

Question 52

What are the three horns of the lateral ventricles?

Answer 52

Frontal/anterior horn Temporal/Inferior horn Occipital/Posterior horn

Question 53

CSF is made by the _____ _____ by ______ cells which line the ventricles.

Answer 53

Choroid plexus. Ependymal cells