Appendix

Question 1

Name the four gross features on the lateral surface of the brain

Answer 1

Cerebrum, Olfactory bulb, brain stem and cerebellum

Question 2

What are the bumps and grooves of the brain called?

Answer 2

The bumps are called gyri, and the grooves are called sulci or, if they are especially deep, fissures

Question 3

Why haven’t we named all the sulk and gyri?

Answer 3

The precise pattern of gyri and sulci can vary considerably from individual to individual, (but many features are common to all human brains. )

Question 4

Name an important sulcus which goes and two gyri beside it and their position

Answer 4

Central sulks runs vertically from the top of the brain to around Halfway down and the postcentral gyrus lies immediately posterior to the central sulcus, and that the precentral gyrus lies immedi- ately anterior to it.

Question 5

What are the neurons in the postcentral and precentral gyri involved in?

Answer 5

The neurons of the postcentral gyrus are involved in somatic sensation, and those of the precentral gyrus control voluntary movement

Question 6

Name the biggest and most obvious fissure in the brain and a gyrus beside it

Answer 6

Lateral (Sylvian) fissure with the superior temporal gyrus just inferior to it

Question 7

What are neurons in the superior temporal gyrus involved in?

Answer 7

Neurons in the superior temporal gyrus are involved in audition

Question 8

How were the different lobes determined?

Answer 8

By convention, the cerebrum is subdivided into lobes named after the bones of the skull that lie over them

Question 9

What part of the cerebral cortex is not seen on the outside of the brain? How is it seen?

Answer 9

A buried piece of the cerebral cortex, called the insula (Latin for “island”), is revealed if the margins of the lateral fissure are gently pulled apart (inset).

Question 10

Name the different areas devoted to the senses and what lobes they are situated in (4)

Answer 10

the visual areas are found in the occipital lobe, the somatic sensory areas are in the parietal lobe, and the auditory areas are in the temporal lobe. On the inferior surface of the parietal lobe (the operculum) and buried in the insula is the gustatory cortex, devoted to the sense of taste

Question 11

What structures make up the brainstem?

Answer 11

diencephalon, midbrain, pons, medulla (It should be noted that some anatomists de- fine the brain stem as consisting only of the midbrain, pons, and medulla.)

See copy for notes

Question 12

What is included in the diencephalon?

Answer 12

thalamus and hypothalamus

Question 13

What is included in the midbrain?

Answer 13

tectum and tegmentum

Question 14

Name some important structures in the forebrain

Answer 14

Corpus callosum, fornix, cingulate gyrus, optic chiasm, amygdala, hippocampus, amygdala

Question 15

What function does the fornix carry out? (2)

Answer 15

The fornix (Latin for “arch) is another prominent fiber bundle that connects the hippo- campus on each side with the hypothalamus.

Some of the axons in the fornix regulate memory storage

Question 16

From a medial view of the brain, what name is given to the largest and most central ventricle shown? To which ventricle is it caudally connected to and what is the name given to this connection as well as the connection of the second ventricle to the spine?

Answer 16

Third ventricle to fourth ventricle (beside cerebellum) via cerebral aqueduct > spinal canal

Question 17

What brain areas lie next to these ventricles and aqueducts?

Answer 17

the thalamus and hypothalamus lie next to the third ventricle; the mid- brain lies next to the aqueduct; the pons, cerebellum, and medulla lie next to the fourth ventricle; and the spinal cord forms the walls of the spinal canal.

Question 18

What paired ventricles sprout from the third ventricle?

Answer 18

The lateral ventricles are paired structures that sprout like antlers from the third ventricle.

Question 19

Describe what is seen from the ventral surface of the brain

Answer 19

nerves emerging from the brain stem; these are the cranial nerves, which are illustrated in more detail later in the Guide. Also notice the X-shaped optic chiasm, just anterior to the hypothalamus. The chiasm is the place where many axons from the eyes decussate from one side to another. The bundles of axons anterior to the chiasm, which emerge from the backs of the eyes, are the
optic nerves. The bundles lying posterior to the chiasm, which disappear into the thalamus, are called the optic tracts. The paired mammillary bodies (Latin for “nipple”) are a prominent feature of the ventral surface of the brain. Notice also the olfactory bulbs, hypothalamus nuclei and the midbrain, pons, and medulla.(learn diagram)

Question 20

What is the name given to the fissure which divides the hemispheres?

Answer 20

Longitudinal cerebral fissure

Question 21

How is the cerebellum divided (gross structures, not neocerebellum etc) (3)

Answer 21

Left cerebellar hemisphere, right cerebellar hemisphere and a midline region called the vermis

Question 22

If the cerebrum and cerebellum is removed, what structures are seen from the dorsal view?

Answer 22

Thalamus, pineal body, superior colliculus, inferior colliculus, midbrain, pons, cerebellar peduncle (cut surface), fourth ventricle (floor)

Question 23

What function does the pineal body carry out and where is it located relative to the thalamus?

Answer 23

The pineal body, lying atop the thalamus, secretes melatonin and is involved in the regulation of sleep and sexual behavior

Question 24

What are the cerebellar peduncles?

Answer 24

The cerebellar peduncles are the large bundles of axons that connect the cerebellum and the brain stem

Question 25

In what two ways can cross sections be made?

Answer 25

Cross sections can be made physically with a knife or, in the case of noninvasive imaging of the living brain, digitally with a magnetic resonance imaging or a com- puted tomography scan.

Question 26

What are the best cross sections to cut for learning the internal organisation of the brain?

Answer 26

For learning the internal organisation of the brain, the best approach is to make cross sections that are perpendicular to the axis de- fined by the embryonic neural tube, called the neuraxis.

The neuraxis bends as the human fetus grows, partic- ularly at the junction of the midbrain and thalamus. Consequently, the best plane of section depends on exactly where we are along the neuraxis.

Question 27

Describe what can be seen from a cross section at the thalamus-telencephalon junction

Answer 27

The telencephalon surrounds the lateral ventricles, and the thalamus surrounds the third ventricle. Notice that in this section, the lateral ventricles can be seen sprouting from the slit-like third ventricle. The hypothalamus, forming the floor of the third ventricle, is a vital control center for many basic bodily functions. Notice that the insula lies at the base of the lateral (Sylvian) fissure, here separating the frontal lobe from the temporal lobe. The heterogeneous region lying deep within the telencephalon, medial to the insula and lateral to the thalamus, is called the basal forebrain.

Question 28

What structure does the fornix fibre groups ‘loop’ around?

Answer 28

The fornix, shown earlier in the medial view of the brain, is shown here in cross section where it loops around the stalk of the lateral ventricle.

Question 29

What three structures make up the basal ganglia?

Answer 29

Three important collections of neurons in the basal tel- encephalon are also shown: the caudate nucleus, the putamen, and the globus pallidus. Collectively, these structures are called the basal ganglia and are an im- portant part of the brain systems that control move- ment

Question 30

What do the neurons in the septal area do?

Answer 30

The neurons of the closely associated septal area contribute axons to the fornix and are involved in memory storage

Question 31

In a slightly more posterior cut, what two nuclei is the thalamus divided into?

Answer 31

The ventral posterior nucleus and the ventral lateral nucleus

Question 32

What are the functions of these two nuclei of the thalamus?

Answer 32

The thalamus provides much of the input to the cerebral cortex, with different thalamic nuclei projecting axons to different areas of cortex. The ventral posterior nucleus is a part of the somatic sensory system and projects to the cortex of the postcentral gyrus. The ventral lateral nucleus and closely related ventral anterior nucleus (not shown) are parts of the motor system and project to the motor cortex of the precentral gyrus.

Question 33

What system is the sub thalamus involved in?

Answer 33

The sub- thalamus is a part of the motor system

Question 34

What function do the mammillary bodies carry out?

Answer 34

the mammillary bodies receive information from the fornix and contribute to the regulation of memory

Question 35

What disease results from degradation of the substantial nigra?

Answer 35

The substantia nigra is also a part of the motor system. Parkinson’s disease results from the de- generation of this structure.

Question 36

From an even more posterior cut, three more nuclei of the thalamus can be seen, what are these?

Answer 36

the pulvinar nucleus and the medial and lateral geniculate nuclei.

Question 37

What are each of these nuclei involved in?

Answer 37

The pulvinar nucleus is con- nected to much of the association cortex and plays a role in guiding attention. The lateral geniculate nucleus relays information to the visual cortex, and the medial geniculate nucleus relays information to the auditory cortex

Question 38

What is hippocampus greek for, relating to how it looks in the brain?

Answer 38

Sea horse

Question 39

What is the ‘core’ of the midbrain (at a rostral midbrain cross section perpendicular to the neuraxis)

Answer 39

The core of the midbrain is the small cerebral aqueduct.

Question 40

What is the ‘roof’ of the midbrain called and what does it consist of?

Answer 40

Here, the roof of the mid- brain, also called the tectum (Latin for “roof”), consists
of the paired superior colliculi.

Question 41

What are the substantial nigra and the red nucleus a part of?

Answer 41

Motor system

Question 42

What is the periaqueductal gray involved in?

Answer 42

important in the control of the somatic pain sensations

Question 43

Where does the input and output from the cerebellar derive?

Answer 43

Much of the input to the cerebellar cortex derives from the pontine nuclei, while the output of the cerebellum is from neurons of the deep cerebellar nuclei

Question 44

Name a function of the reticular formation and where it runs to and from

Answer 44

The reticular formation runs from the midbrain to the medulla at its core, just under the cerebral aqueduct and fourth ventricle. One function of the reticular forma- tion is to regulate sleep and wakefulness

Question 45

What is a specific function of the pontine reticular formation

Answer 45

In addition, a function of the pontine reticular formation is to control body posture

Question 46

Name six structures of the medulla and their respective functions

Answer 46

At the very floor of the medulla lie the medullary pyramids, huge bundles of axons descending from the forebrain toward the spinal cord. The pyramids contain the corticospinal tracts, which are involved in the control of voluntary movement.
Several nuclei that are important for hearing are also found in the rostral medulla: the dorsal and ventral cochlear nuclei, and the superior olive.
Also shown are the inferior olive, important for motor control,
and the raphe nucleus, important for the modulation of pain, mood, and wakefulness

Question 47

What structure in the mid-medulla is involved in taste?

Answer 47

The gustatory nucleus, a part of the larger solitary nucleus, serves the sense of taste

Question 48

What structure in the mid-medulla is involved in balance?

Answer 48

The vestibular nuclei serve the sense of balance

Question 49

What purpose do the dorsal column nuclei serve?

Answer 49

receive somatic sensory information from the spinal cord. Axons arising from the neurons in each dorsal column nucleus cross to the other side of the brain (decussate) and ascend to the thalamus via the medial lemniscus.

Question 50

What is the visceral nervous system devoted to?

Answer 50

devoted to the regulation of the internal organs, glands, and vasculature.

Question 51

Give another name for the visceral nervous system and why it is called that

Answer 51

Because this regulation occurs automatically and is not under direct conscious control, this system is called the autonomic nervous system, or ANS.

Question 52

Name the two most important divisions of the ANS

Answer 52

The two most important divisions of the ANS are called the sympathetic and parasympathetic divisions.

Question 53

What does the sympathetic system consist of and what do they communicate with?

Answer 53

the sympathetic division of the ANS consists of a chain of ganglia that runs along the side of the vertebral column. These ganglia communicate with the spinal nerves, with one another, and with a large number of internal organs.

Question 54

How is the parasympathetic system organised differently?

Answer 54

Much of the para- sympathetic innervation of the viscera arises from the vagus nerve, one of the cranial nerves emerging from the medulla. The other major source of parasympathetic fibers is the sacral spinal nerves.

Question 55

Where do most of the cranial nerves lead to in the brain?

Answer 55

the cranial nerves have associated cranial nerve nuclei in the midbrain, pons, and medulla. Examples are the cochlear and vestibular nuclei, which receive information from cranial nerve VIII.

Question 56

What two pairs of arteries supply blood to the brain?

Answer 56

the vertebral arteries and the internal carotid arteries.

Question 57

What do the vertebral arteries and the internal carotid arteries join to form?

Answer 57

The vertebral arteries converge near the base of the pons to form the unpaired basilar artery.

Question 58

What does the basilar artery branch off into?

Answer 58

Right and left Posterior and Superior cerebral arteries

Question 59

Describe the collection of blood vessels with a particular shape and what this collection is called

Answer 59

the posterior cerebral arteries send branches, called posterior communicating arteries, that connect them to the internal carotids. The inter- nal carotids branch to form the middle cerebral arteries and the anterior cerebral arteries. The anterior cere- bral arteries of each side are connected by the anterior communicating artery. Thus, there is a ring of con- nected arteries at the brain’s base, formed by the poste- rior cerebral and communicating arteries, the internal carotids, and the anterior cerebral and communicating arteries. This ring is called the circle of Willis.