Chapter 12- The Central Nervous System

Front 1

Central Nervous System is composed of what?

Back 1

composed of the brain and spinal cord

Front 2

Cephalization

Back 2

Elaboration of the anterior portion of the CNS

Increase in number of neurons in the head

Highest level is reached in the human brain

Front 3

The Brain is composed of what?

Back 3

Composed of wrinkled, pinkish gray tissue

Front 4

Surface anatomy of the brain:

Back 4

cerebral hemispheres,
cerebellum,
brain stem

Front 5

During the first 26 days of development:

Back 5

Ectoderm thickens forming the neural plate

The neural plate invaginates, forming the neural groove

The neural groove fuses dorsally and forms the neural tube

Front 6

Primary Brain Vesicles

Back 6

The anterior end of the neural tube expands and constricts to form the three primary brain vesicles

Front 7

3 primary brain vesicles:

Back 7

Prosencephalon
Mesencephalon
Rhombencephalon

Front 8

Prosencephalon

Back 8

forebrain

Front 9

Mesencephalon

Back 9

midbrain

Front 10

Rhombencephalon

Back 10

hindbrain

Front 11

When do Secondary Brain Vesicles form?

Back 11

In week 5 of embryonic development, secondary brain vesicles form

Front 12

Secondary Brain Vesicles

Back 12

Telencephalon and diencephalon arise from the forebrain

Mesencephalon remains undivided

Metencephalon and myelencephalon arise from the hindbrain

Front 13

Adult Brain Structures:
Telencephalon

Back 13

cerebrum:
cortex,
white matter,
basal nuclei

Front 14

Adult Brain Structures:
Diencephalon

Back 14

thalamus,
hypothalamus,
epithalamus

Front 15

Adult Brain Structures:
MeSencephalon

Back 15

brain stem: midbrain

Front 16

Adult Brain Structures:
MeTencephalon

Back 16

brain stem: pons

Front 17

Adult Brain Structures:
Myelencephalon

Back 17

brain stem: medulla oblongata

Front 18

Spinal Cord

Back 18

Central cavity surrounded by a gray matter core

External to which is white matter composed of myelinated fiber tracts

Front 19

Brain

Back 19

Similar to spinal cord but with additional areas of gray matter

Cerebellum has gray matter in nuclei

Cerebrum has nuclei and additional gray matter in the cortex

Front 20

What do the ventricles of the brain arise from?

Back 20

Arise from expansion of the lumen of the neural tube

Front 21

The ventricles of the brain are:

Back 21

The paired C-shaped lateral ventricles

The third ventricle found in the diencephalon

The fourth ventricle found in the hindbrain dorsal to the pons

Front 22

Cerebral Hemispheres

Back 22

Form the superior part of the brain and make up 83% of its mass

Contain ridges (gyri) and shallow grooves (sulci)

Contain deep grooves called fissures

Are separated by the longitudinal fissure

Front 23

Deep sulci divide the hemispheres into five lobes:

Back 23

Frontal, parietal, temporal, occipital, and insula

Front 24

Central sulcus

Back 24

separates the frontal and parietal lobes

Front 25

Parieto-occipital sulcus

Back 25

separates the parietal and occipital lobes

Front 26

Lateral sulcus

Back 26

separates the parietal and temporal lobes

Front 27

The precentral and postcentral gyri border the

Back 27

central sulcus

Front 28

The cerebral cortex

Back 28

superficial gray matter; accounts for 40% of the mass of the brain

It enables sensation, communication, memory, understanding, and voluntary movements

No functional area acts alone; conscious behavior involves the entire cortex

Front 29

Hemispheres of the cerebral cortex

Back 29

Each hemisphere acts contralaterally (controls the opposite side of the body)

Hemispheres are not equal in function

Front 30

The three types of functional areas are of the cerebral cortex:

Back 30

Motor areas – control voluntary movement

Sensory areas – conscious awareness of sensation

Association areas – integrate diverse information

Front 31

Cerebral Cortex: Motor Areas

Back 31

Primary (somatic) motor cortex
Premotor cortex
Broca’s area
Frontal eye field

Front 32

Primary Motor Cortex

Back 32

Allows conscious control of precise, skilled, voluntary movements

Front 33

Premotor Cortex

Back 33

Controls learned, repetitious, or patterned motor skills

Coordinates simultaneous or sequential actions

Involved in the planning of movements

Front 34

Broca’s Area

Back 34

A motor speech area that directs muscles of the tongue

Is active as one prepares to speak

Front 35

Frontal Eye Field

Back 35

Controls voluntary eye movement

Front 36

Sensory Areas

Back 36

Primary somatosensory cortex

Somatosensory association cortex

Visual and auditory areas

Olfactory, gustatory, and vestibular cortices

Front 37

Primary Somatosensory Cortex

Back 37

Located in the postcentral gyrus, this area:

Receives information from the skin and skeletal muscles

Exhibits spatial discrimination

Front 38

Somatosensory Association Cortex

Back 38

Located posterior to the primary somatosensory cortex

Integrates sensory information

Forms comprehensive understanding of the stimulus

Determines size, texture, and relationship of parts

Front 39

Visual Areas:
Primary visual (striate) cortex

Back 39

Seen on the extreme posterior tip of the occipital lobe

Receives visual information from the retinas

Front 40

Visual Areas:
Visual association area

Back 40

Surrounds the primary visual cortex

Interprets visual stimuli (e.g., color, form, and movement)

Front 41

Auditory Areas:
Primary auditory cortex

Back 41

Located at the superior margin of the temporal lobe

Receives information related to pitch, rhythm, and loudness

Front 42

Auditory Areas:
Auditory association area

Back 42

Located posterior to the primary auditory cortex

Stores memories of sounds and permits perception of sounds

Front 43

Association Areas

Back 43

Prefrontal cortex
Language areas
General (common) interpretation area
Visceral association area

Front 44

Prefrontal Cortex

Back 44

Located in the anterior portion of the frontal lobe

Involved with intellect, cognition, recall, and personality

Necessary for judgment, reasoning, persistence, and conscience

Closely linked to the limbic system (emotional part of the brain)

Front 45

Where are the language areas located?

Back 45

Located in a large area surrounding the left (or language-dominant) lateral sulcus

Front 46

Language Area:
Wernicke's Area

Back 46

sounding out unfamiliar words

Front 47

Language Area:
Broca's Area

Back 47

speech preparation and production

Front 48

Language Area:
Lateral prefrontal cortex

Back 48

language comprehension and word analysis

Front 49

Language Area:
Lateral and ventral temporal lobe

Back 49

coordinate auditory and visual aspects of language

Front 50

General (Common) Interpretation Area

Back 50

Ill-defined region including parts of the temporal, parietal, and occipital lobes

Found in one hemisphere, usually the left

Integrates incoming signals into a single thought

Involved in processing spatial relationships

Front 51

Visceral Association Area

Back 51

Located in the cortex of the insula

Involved in conscious perception of visceral sensations

*Lets you know if you have upset stomach or full bladder, etc

Front 52

Lateralization

Back 52

each hemisphere has abilities not shared with its partner

Front 53

Cerebral dominance

Back 53

designates the hemisphere dominant for language

Front 54

Left hemisphere

Back 54

controls language, math, and logic

Front 55

Right hemisphere

Back 55

controls visual-spatial skills, emotion, and artistic skills

Front 56

Cerebral White Matter consists of:

Back 56

deep myelinated fibers and their tracts

Front 57

Cerebral White Matter is responsible for communication between:

Back 57

The cerebral cortex and lower CNS center, and areas of the cerebrum

Front 58

Diencephalon

Back 58

Central core of the forebrain

Consists of three paired structures – thalamus, hypothalamus, and epithalamus

Encloses the third ventricle

Front 59

Thalamus

Back 59

Paired, egg-shaped masses that form the superolateral walls of the third ventricle

Front 60

Thalamic Function

Back 60

Afferent impulses converge and synapse in the thalamus

Impulses of similar function are sorted out, edited, and relayed as a group

*All inputs ascending to the cerebral cortex pass through the thalamus

Mediates sensation, motor activities, cortical arousal, learning, and memory

Front 61

Hypothalamus is located:

Back 61

below the thalamus

Front 62

Hypothalamus:
Mamillary bodies

Back 62

Small, paired nuclei bulging anteriorly from the hypothalamus

Relay station for olfactory pathways

Front 63

Hypothalamus:
Infundibulum

Back 63

stalk of the hypothalamus; connects to the pituitary gland

Main visceral control center of the body

Front 64

Hypothalamic Function

Back 64

Regulates blood pressure, rate and force of heartbeat, digestive tract motility, rate and depth of breathing, and many other visceral activities

Perception of pleasure, fear, and rage

Maintains normal body temperature

Regulates feelings of hunger and satiety

Regulates sleep and the sleep cycle

Front 65

Epithalamus is located:

Back 65

Most dorsal portion of the diencephalon;

forms roof of the third ventricle

Front 66

Epithalamus:
Pineal gland

Back 66

extends from the posterior border and secretes melatonin

Front 67

Melatonin

Back 67

a hormone involved with sleep regulation, sleep-wake cycles, and mood

Front 68

Brain stem consists of what 3 regions?

Back 68

midbrain,
pons,
medulla oblongata

Front 69

Brain stem controls & provides:

Back 69

Controls automatic behaviors necessary for survival

Provides the pathway for tracts between higher and lower brain centers

*Associated with 10 of the 12 pairs of cranial nerves

Front 70

Medulla:
Cardiovascular control center

Back 70

adjusts force and rate of heart contraction

Front 71

Medulla:
Respiratory centers

Back 71

control rate and depth of breathing

Front 72

Medulla:
Additional centers

Back 72

regulate vomiting, hiccuping, swallowing, coughing, and sneezing

Front 73

The Cerebellum

Back 73

Located dorsal to the pons and medulla

Protrudes under the occipital lobes of the cerebrum

Makes up 11% of the brain’s mass

Provides precise timing and appropriate patterns of skeletal muscle contraction

Cerebellar activity occurs subconsciously

Front 74

How Cerebellar Processing Works:

Back 74

Cerebellum receives impulses of the intent to initiate voluntary muscle contraction

Proprioceptors and visual signals “inform” the cerebellum of the body’s condition

Cerebellar cortex calculates the best way to perform a movement

A “blueprint” of coordinated movement is sent to the cerebral motor cortex

Front 75

Cerebellar Cognitive Function

Back 75

Plays a role in language and problem solving

Recognizes and predicts sequences of events