6. Gross Anatomy Of The Brain And Spinal Cord

Front 1

How much cortex does the human brain have?

Back 1

2.5 ft, but most of it is hidden in depths of sulci.

Front 2

What is the relation of wt. and size of brain and a persons intelligence?

Back 2

No relation. Intelligence is due to the complexity of conections in grey matter.

Front 3

What part of the brain makes up most of the human brain?

Back 3

Forebrain

Front 4

Are all persons sulci and gyri the same?

Back 4

No, there is individual variablity in the sulci and gyri

Front 5

What are deep sulci called?

Back 5

Fissures

Front 6

What is the size of the brain at birth?

Back 6

Approx. 400grams, but the weight triples in the first 3 years.

Front 7

What does a rat's brain look like, other than size, compared to a human brain?

Back 7

Very smooth surface. Called lissencephalic

Front 8

What is the size of the brain at age 18?

Back 8

1400 grams, from ages 11-50, but can range any where from 1100 to 1700 grams.

Front 9

What happens to the weight of the brain as we age?

Back 9

After age 50, the weight of the brain begins to decrease.

Front 10

What is the increase in size of the brain due to?

Back 10

Myelination and growth of neuronal processes, also called dendritic arborization. There are not a lot of new neurons generated after birth.

Front 11

1. Brain convolutions are called what?

2. What are these convolutions seperated by?

Back 11

1. Gyri
2. Sulci

Front 12

What do the convolutions in the brain increase?

Back 12

Surface Area

Front 13

How do convolutions vary from one brain to the next?

Back 13

Many gyri and sulci are constant from brain to brain, but the PATTERN of convolutions can differ from brain to brain AND from hemisphere to hemisphere

Front 14

What seperates the lobes of the brain?

Back 14

Prominent SULCI

Front 15

What does our text book author believe as far as how many lobes the brain has?

Back 15

Nolte describes 5 lobes, and 1 cortical area that is not a true lobe.

Front 16

What is the largest lobe in the brain? and just HOW large is it?

Back 16

Frontal lobe, 1/3 of cortical surface area is here. (gray matter)

Front 17

What are the boundaries for the frontal lobe?

Back 17

Everything in front of the central sulcus.

Front 18

What functions of the brain does the cortical surface have?

Back 18

Consciousness, memory, creativity, higher level thinking skills, etc.

Front 19

What are the four functional areas of the frontal lobe?

Back 19

1. Primary motor cortex
2. Premotor cortex
3. Broca's Area
4. Prefrontal cortex

Front 20

What is found in the primary motor cortex of the frontal lobe?

Back 20

Descending motor pathways/tracts start here. Axons go thru the prosencephalon. Involved in the initiation of voluntary movements, motor activity.

Front 21

Where is the primary motor cortex located specifically?

Back 21

In the pre-central gyrus

Front 22

Where is the premotor cortex located?

Back 22

In the superior and middle frontal gyrus'.

Front 23

What is the premotor cortex responsible for?

Back 23

Also responsible for initiating voluntary movement.

Front 24

Where is the Broca's Area located? (general) Name it's two specific areas.

Back 24

In a triangular area within the frontal lobe. Has two parts: 1. Pars Opercular and 2. Pars Triangular

Front 25

What is the Broca's area responsible for?

Back 25

Production and expression of written and spoken language.

Front 26

Where is the prefrontal cortex located?

Back 26

In the area comprising the remainder of the frontal lobe. (all areas that are not taken)

Front 27

What is the prefrontal cortex responsible for?

Back 27

Complex thinking, personality, creativity, delayed gratification, imagination, ability to do good things for others, insight

Front 28

What are the 3 functional areas of the parietal lobes?

Back 28

1. Primary somatosensory cortex (sensory map of body)
2. Much of the inferior parietal lobule
3. The rest of the parietal lobe (superior parietal lobule and part of the inferior parietal lobule)

Front 29

What is the primary somatosensory cortex responsible for?

Back 29

"body sensation", proprioception, touch, pain, temperature, "feel"

Front 30

What is "much of the inferior parietal lobule" responsible for?

Back 30

Comprehension of language

Front 31

What is a Homonculous Map?

Back 31

When parts of the body surround the part of the brain that their function originates from.

Front 32

What is the "rest of the parietal lobe (sup. parietal lobule and part of the inf. parietal lobule)" responsible for?

Back 32

Spatial orientation and perception. (Identifying where you are on a map, getting from point A to B)

Front 33

What are the three general functional areas of the temporal lobe?

Back 33

1. Primary auditory cortex
2. Comprehension of Language (Wernicke's area is in both temporal and parietal lobes)
3. Hippocampus and parahippocampal gyrus

Front 34

What is the primary auditory cortex responsible for?

Back 34

Being able to discriminate sounds and put them together as words, music, etc. Understanding what words mean.

Front 35

What are the hippocampus and parahippocampal gyrus responsible for?

Back 35

Learning and memory

Front 36

What is the occipital lobe associated with? and where is it located?

Back 36

The visual system, visual assoication area. Located in the back of the brain.

Front 37

Where is the limbic lobe located?

Back 37

Part of it is in the frontal, parietal and temporal lobes.

Front 38

What is the limic lobe responsible for?

Back 38

Mediates emotions, drive-related behavior, memory, eating, fighting, processes emotions (anger, humor, satisfaction). Very difficult to measure and study

Front 39

Where is the insula located?

Back 39

An AREA (not a lobe) that is deep in the lateral fissure

Front 40

What is the insula responsible for?

Back 40

Not sure what it does, function unknown. Visual processing?

Front 41

What ventricle is the diencephalon associated with?

Back 41

The third ventricle

Front 42

What are four structures that are a part of the diencephalon?

Back 42

1. Thalamus
2. Hypothalamus
3. Epithalamus
4. Subthalamus

Front 43

Where is the thalamus located and what is it responsible for?

Back 43

Located on either side of the 3rd ventricle. Responsible for All sensory information, except olfaction (smell). Info. has to synapse in thalamus before it gets to the cortex, so this area is VERY important!! Senses are located here: see, touch, hear, etc.

Front 44

What is the hypothalamus responsible for?

Back 44

Vissceral/Endocrine control center, autonomic nervous system, mediates emotions and drives.

Front 45

Where is the hypothalamus located?

Back 45

Hypo = below, the thalamus

Front 46

What structure is found in the epithalamus? What does this structure do?

Back 46

A pine cone shaped Pineal gland, which produces and releases mela?

Front 47

Where is the epithalamus?

Back 47

"epi" means upon. Upon the thalamus

Front 48

What is found in the subthalamus?

Back 48

Part of the basal ganglia, which has motor functions

Front 49

What passes through the brainstem?

Back 49

Ascending and descending axons that go to and from the spinal cord and cerebral cortex. Basically, lots of axons pass thru here to get to somewhere else!

Front 50

What three structures make up the brian stem?

Back 50

Midbrain, pons and medulla

Front 51

Most (blank) are found in the brainstem.

Back 51

Cranial Nerves

Front 52

What structure covers most of the posterior surface of the brainstem?

Back 52

The cerebellum

Front 53

What is another name (nickname) for the cerebellum

Back 53

"Little brain"

Front 54

How is the cerebellum attached to the brainstem?

Back 54

Via cerebellar peduncles

Front 55

What is the primary function of the cerebellum?

Back 55

Motor function, helps with coordination and balance

Front 56

What form spinal nerves?

Back 56

Dorsal and ventral spinal roots

Front 57

The spinal cord is the location of what kind of output?

Back 57

Motor

Front 58

What is located in the ventral horn of the spinal cord?

Back 58

Cell bodies that innervate skeletal muscles throughout body. Autonomic preganglionic neurons

Front 59

What test is related to the spinal cord?

Back 59

Stretch reflex-spinal cord reflex

Front 60

Describe the segmental organization of the spinal cord.

Back 60

Segment is indiciated by spinal nerves

Front 61

Why does the spinal cord not go all the way down to the sacrum? How does this relate to the segmental orgainization?

Back 61

The vertebral bodies grow faster than the spinal cord, so the spinal cord ends about L2. The spinal nerves still exit out the appropriate vertebrae, because the dorsal and ventral spinal roots just get longer and longer in order to obliquely exit at the approriate site.

Front 62

Where are there enlargements on the spinal column? Why are there enlargements here?

Back 62

At the cervical and lumbar areas. These areas supply the upper and lower extremities and therefore contain increased numbers of motor neurons and interneurons, which require a larger area.

Front 63

Where is it ok to do a spinal tap?

Back 63

Below L2 and up to S2. No spinal cord there.

Front 64

What is the conus medullaris?

Back 64

The pointed, caudal end of the spinal cord.

Front 65

What is the cauda equina?

Back 65

"horse's tail" Collection of dorsal and ventral roots

Front 66

What is the filum terminale?

Back 66

An extension of the pial covering of the conus medullaris anchoring the caudal end of the cord to the end of the dural tube/sac.

Front 67

Gray matter is divided into (blank) and white matter is divided into (blank)

Back 67

Gray = horns
White = funiculi

Front 68

Where is the ventral (anterior) median fissure located on the spinal cord? Describe.

Back 68

On the anterior aspect of the spinal cord. Its a deep groove that extends almost to the center of the cord.

Front 69

Describe where the dorsal median sulus is on the spinal cord.

Back 69

Midline of the posterior aspect of the spinal cord. Lies between the fasciculus gracilis. Barely present, very shallow

Front 70

Where is the ventrolateral (anterolateral) sulcus on the spinal cord?

Back 70

It's where the ventral (anterior) rootlets LEAVE, on either side of the ventral median fissure. Poorly defined.

Front 71

Where is the dorsolateral (posterolateral) sulcus on the spinal cord?

Back 71

It's where the dorsal (posterior) rootlets ENTER. Just lateral to the fasciculus cuneatus. Shallow

Front 72

Where is the dorsal (posterior) intermediate sulcus on the spinal cord?

Back 72

Just lateral to the dorsal median sulcus, but only present in the cervical and upper thoracic levels. Seperates fasciculus cuneatus and fasciculs gracilis

Front 73

What are denticulate ligaments?

Back 73

Come off of pia mater, tooth-shaped. Btwn spinal nerves that anchor the spinal cord within the dural sac.

Front 74

Is the epidural space in the spine real or potential?

Back 74

REAL

Front 75

What is attached to the inner surface of the dura?

Back 75

Arachnoid mater

Front 76

How many layers does the dura mater of the spine have? It is suspended in what structure in the spine?

Back 76

Single layer, suspended in vertebral canal

Front 77

Within a cross section of the spinal cord there are three funiculus (white matter). Name them.

Back 77

Posterior, lateral and anterior funiculus.

Front 78

The anterior/ventral horn of the spinal cord contains what?

Back 78

Motor neurons

Front 79

The posterior/dorsal horn of the spinal cord contains what?

Back 79

Sensory neurons

Front 80

What is the substantia gelatinosa?

Back 80

A distinctive region of gray matter that caps the posterior horn. Sensory fibers carry pain and temperature info.

Front 81

What is the body of the posterior horn contain?

Back 81

Interneurons and projection neurons that transmit somatic and visceral sensory info.

Front 82

What is in the intermediate gray matter of the spinal cord?

Back 82

preganglionic autonomic neurons

Front 83

What does the lateral horn contain and where is it located?

Back 83

Contains preganglionic sympathetic neurons for the entire body which lie btwn segments T1 and L2. It is a pointy lateral extension to the intermediate gray area.

Front 84

Where will these preganglionic sympathetic neurons synapse?

Back 84

In the sympathetic chain

Front 85

Where is the sacral parasympathetic preganglionic nucleus located?

Back 85

Same general location as the lateral horn, except in segments S2 - S4

Front 86

Where is Clarke's nucleus (nucleus dorsalis) located? and what does it do?

Back 86

T1 - L2, right above the central canal. Relays information to the cerebellum for proprioception of skeletal muscles, especially legs

Front 87

What is Rexed's Laminae?

Back 87

A roman numeral system used to figure out where spinal cord lesion/injury is.

Front 88

How many layers of neurons are in the Rexed's Laminae? and where do you begin to number?

Back 88

10, begin from the dorsal horn of the spinal cord.

Front 89

What numbers are located in the posterior horn? and what kinds of neurons are they?

Back 89

I-VI (1-6) are sensory neurons

Front 90

What are VII, VII, IX and X?

Back 90

VII: Intermediate gray matter
VIII: Interneurons in anterior horn (don't leave spinal cord)
IX: motor neurons in anterior horn, form spinal nerves that innervate skeletal muscles
X: surrounds central canal, grey matter

Front 91

What are the two sub divisions of the posterior funiculs?

Back 91

Fasciculus gracilis and fasciculs cuneatus

Front 92

What is the fasciculus proprius? What is in it and what is it's function?

Back 92

It is the white matter closest to the gray matter. Has axons that project a few spinal levels. Only travel a short distance in spinal cord. Axons interconnect spinal cord segments, as motor activity requies a linkage of several spinal levels. Basically they allow for coordination within the spinal cord for motor movements.

Front 93

What is the function of the anterior white commissure? and where is it located?

Back 93

A thin zone of white matter below area X. It's where sensory information crosses from one side of the spinal cord to the other. Can cut here to block pain impulses.