Neuroscience Slides Exam 1

Front 1

What makes up the forebrain?
What makes up the brainstem?
What makes up the hindbrain?

Back 1

cerebrum and diencephalon
midbrain, pons, and medulla
pons, medulla, and hindbrain

Front 2

What fissure separates the two cerebral hemispheres?

Back 2

Longitudinal fissure

Front 3

What separates frontal and parietal lobes? What separates the lateral lobe form the frontal and parietal lobes?

Back 3

Central sulcus
lateral fissure

Front 4

What gyrus is superior to the corpus callosum? What does it handle?

Back 4

cingulate gyrus
emotion

Front 5

What occupies the cortical midline?

Back 5

limbic lobe

Front 6

What is the function of the following structures:

cerebrum
thalamus
hypothalamus
mesencephalon
pons
medulla
cerebellum

Back 6

conscious thought
sensory relays
homeostasis
consciousness and visual/auditory data
sensory relay, motor (peduncles)
autonomic and thalamus relay
motor control

Front 7

What are the functions of the lobes?

Back 7

Frontal lobe: personality and higher centers for voluntary motor activities (Primary motor cortex- seen in red)
Parietal lobe: peripheral sensations (primary somatosensory cortex- seen in blue)
Temporal lobe: sensations of smell, taste (in insula) & hearing
Occipital lobe: vision

Front 8

What condition has slurred, slow words? Which condition has phonemic paraphrasia?

Back 8

lesions in Broca's area
lesions in Wernicke's area

Front 9

What do right sided lesions cause in Broca's and Wenicke's area?

Back 9

dull monotone speech
inability to understand tone

Front 10

What are basal ganglia?

Back 10

series of interconnected nuclei embedded in the subcortical white matter involved in the control of movement (plan, initiate, and maintain voluntary motor activities)

Front 11

What makes up the basal ganglia? what does damage to the area cause?

Back 11

striatum, pallidum, substantia nigra, and subthalamic nucleus

Negative signs: loss of motor function
Positive signs: new motor activities, or an inability to suppress unwanted motor function

Front 12

What are the mamillary bodies?

Back 12

olfactory pathway relay station that are part of the hypothalamus

Front 13

What are the 3 steps of sensory input?
What are the 2 steps of motor output?

Back 13

Neuron 1 carries information to the CNS
Neuron 2 carries the information to the contralateral thalamus
Neuron 3 carries the information to the cortex

Neuron 1 (the upper motor neuron) carries information from the cortex to a lower motor neuron on the contralateral side of the CNS
Neuron 2 (the lower motor neuron) carries the information from the CNS to a muscle

Front 14

What are the functions of the meninges?

Back 14

Cover and protect the CNS
Protect blood vessels and enclose venous sinuses
Contain CSF (Keep the brains suspended in a bath of CSF)
Form partitions within the skull that prevents
movement within the skull

Front 15

What layers make up the meninges?

Back 15

Dura or pachymeninx = tough mother, 2 layers
- periosteal and the menegeal
Arachnoid = web like, -appears like syran wrap
subarachnoid space with trabeculae (delicate
collagen and elastic fibers)
The Pia adheres to the brain & is rich in capillaries
follows contour of the brain

Front 16

Where are dura not fused?

Back 16

dural sinuses

Front 17

What artery and nerve supply the dura?

Back 17

middle meningeal artery
trigeminal nerve

Front 18

What are the 4 septa?

Back 18

falx cerebri - between the cerebral hemispheres (free edge follows the corpus callosum)
tentorium cerebelli - transverse septum separating the occipital lobe from the cerebellum
falx cerebelli - septum between the cerebellar hemispheres
diaphragma sellae - roof of the hypophysis fossa (sella turcica), perforated by the infundibular stalk

Front 19

What are the Arachnoid villi?

Back 19

protrude superiorly and permit
CSF to be absorbed into venous blood

Front 20

What returns CSF to the blood via the superior sagittal sinus?

Back 20

granulations

Front 21

What are 2 potential spaces?

Back 21

epidural
subdural

Front 22

What is a countrecoup injury?

Back 22

damage to brain during rebound collision with opposite side the skull

Front 23

What does a epidural hematoma look like? What likely tears?

Back 23

lens
middle meningeal artery

Front 24

What shape is a subdural hematome and why?
What tears?

Back 24

crescent-shaped
bounded by dura and arachnoid
bridging veins

Front 25

What causes worst headache of life in subarachnoid hematoma? What tears? how does it look?

Back 25

meningeal irritation
arteries in pial membrane
texaco star

Front 26

Where is the blood brain barrier absent?

Back 26

the choroid plexus, hypothalamus, and pineal gland

Front 27

What are the 4 components of corpus callosum?

Back 27

rostrum
genu
body
splenium

Front 28

Where does the brain receive its blood supply?

Back 28

80% of the brain’s
blood supply comes from the carotid,
and the remaining 20% from the vertebral

Front 29

What is the difference between cortical and central branches?

Back 29

Cortical (Circumferential) Branches
Supply External Brain Structures
Central (Penetrating) Branches
Small
Penetrate ventral surface to supply internal brain structures

Front 30

What do the anterior choroidal arteries supply?

Back 30

Anterior hippocampus &
Posterior limb of the internal capsule

Front 31

What does an interruption in the anterior cerebral arteries cause?

Back 31

Paralysis of legs and feet
Difficulty in prefrontal lobe functions of cognitive thinking, judgment, motor initiation and self monitoring

Front 32

what are watershed areas?

Back 32

Oerlap in arterial perfusion

Front 33

What is a transient ischemic attack?

Back 33

Transient occlusion of an intracranial artery due to thromboembolism
Symptoms resolve following rapid fragmentation and dissolution of the microemboli/thrombus

Front 34

What is an embolism and thrombosis?

Back 34

Embolism: object/piece of a clot (from another part of the body) which travels through artery until it gets stuck
Thrombosis: object originating within a blood vessel: local buildup of fatty substances usually at a bifurcation of artery, these can rupture leading to bleeding and clotting

Front 35

What is a lacunar infarct?

Back 35

Occlusion of small vessels (200-400 mm)
internal capsule/corona radiata,
thalamus,
basal ganglia,
brain stem

Front 36

What is an Arteriovenous Malformations?

Back 36

Appear tangled mass of arteries and veins
Blood vessel defects that occur before birth
Can cause hemorrhagic strokes

Front 37

What is the Monro-Kellie Doctrine?

Back 37

As an intracranial mass increases in size

CSF is displaced into the spinal canal
Blood volume is reduced in the brain
Displacement of brain tissue - herniation

Front 38

What are the 4 types of herniation and the 2 types?

Back 38

Cingulate or subfalcine: compress anterior cerebral arteries)
Transtentorial herniation: ultimately the brainstem is compressed which results in death if the pressure is not removed
Tonsillar (chiari malformation) can be incidental, or life threatening
Cerebellar herniation (increased p2 in posterior fossa can push cerebellum up

The supratentorial (occurs above the tentorial notch)
Uncal, transtentorial (central), cingulate, and
Transcalvarial
The infratentorial (occurs below the tentorial notch)
upward transtentorial and tonsillar.

Front 39

What kind of neurons bleong in the afferent category? What neurons belong in the effernt category? CNS?

Back 39

unipolar and psuedopolar
multipolar
anaxonic

Front 40

How is interneuronal fow carried? Intraneuronal?

Back 40

Chemical
electrical

Front 41

What is the point of the cytoskeleton?

Back 41

structural suport
compartmentilzation
Guidance during development, growth, neuronal
repair and regeneration
Aid in the transport of substances to and from the
cell body (axonal transport)

Front 42

Which cytoskeleton elements are polar? Non-polar? Which uses ATP? Which used GTP? Nucleotide binding?

Back 42

Actin and microtubules
neurofilaments
actin
microtubules
neurofilaments

Front 43

What are the main 2 functions of neurofilaments?

Back 43

structure and help in axonal transport

Front 44

What is the specific funciton of actin filaments? What 3 things are they associated with?

Back 44

Help neurons interact with extracellular matrixand with other cells (tight junctions/gap junctions)
Associated with:
presynaptic terminals
dendritic spines
growth cones

Front 45

Which motor protein is anterograde? Retrograde?

Back 45

kinesin
dyenein

Front 46

How does phosphorylation affect microtubules? What is this indicative of?

Back 46

destabilizes
alzheimers

Front 47

What is transported by Component A fast anterograde?

Back 47

neurotransmitters & neuropeptides
membrane lipids & glycolipids
membrane-associated enzymes (e.g. ACh-esterase)
receptor proteins

Front 48

What is transported by Component B tranport?

Back 48

Unbound materials transported (mitochondria)
does not require cell body…. or axon (just the axoplasm)

Front 49

What is the significance of the slow anterograde axonal transport?

Back 49

cytoskeletal elements, e.g. actin, tubulin, MTs, NFs, MFs
soluble enzymes, e.g. glycolytic enzymes

Primary mediator of axon growth and regeneration

Limiting factor of regeneration

Front 50

What is the purpose of fast retrogrde transport? What does it carry and in what container?

Back 50

Returns old membrane components from the axon
terminal to the cell body for recycling
Transported materials are packaged into organelles
materials transported include:
trophic factors & growth factors
used materials bound for lysosomal degradation
viruses, e.g. rabies, polio, herpes simplex
dyes, e.g. HRP

Front 51

Which cells are scavengers?

Back 51

microglia
think macrophages

Front 52

What is the difference between macorglia and microglia?

Back 52

Macroglia, which include astrocytes, oligodendrocytes,
and ependymal cells, are of ectodermal origin
Microglia, the macrophages of the CNS, are of
mesodermal origin.

Front 53

What are the 4 differences between glia and neurons?

Back 53

Glial cells differ from neurons in that (1) they do not form
synapses; (2) they have only one type of process; (3) they
retain the ability to divide throughout their life span; and
(4) they are electrically inexcitable

Front 54

What is the purpose of Schwann cells?

Back 54

Schwann cells supply the myelin of the PNS: Each Schwann cell commits itself to a portion of one axon
Help determine distribution of voltage-gated channels along axon
Regulate synaptic communication at NMJ (neuromuscular junction), including likely release of transmitters
Important in recovery from axon damage: supply growth factors, “channel” for new growth

Front 55

How are oligodendrocytes different from Schwann cells?

Back 55

A single oligodendrocyte sends out multiple processes
Each process wraps around a portion of an axon
Thus a single oligodendrocyte contributes myelin to several (40?) central axons

Each Schwann cell commits itself to a portion of one axon

Front 56

What are the most abundant and versatile glial cells?

Back 56

astrocytes

Front 57

What is the purpose of astrocytes?

Back 57

Support and brace neurons
Anchor neurons to their nutrient supplies
Guide migration of young neurons
Control the chemical environment

Front 58

What are radial glial cells?

Back 58

Supply guidance to neurons during neural migration

Are progenitors for fibrous & protoplasmic astrocytes

Front 59

What and where are ependymal cells?

Back 59

Ependymal cells – range in shape from squamous to columnar. They line the central cavities of the brain and spinal column

They line the ventricular system

Front 60

Describe microglia?

Back 60

Arise from mesoderm not neuroectoderm
Mediate immune responses
Become reactive in response to damage
more microglia are recruited to the damaged area
phagocytose pathogens and cell debris in the CNS
release cytokines (IL-1, TNF-a)
Susceptible to HIV infection

Front 61

What causes transient loss of function?
What causes permanent loss?

Back 61

edema
constant pressure
anoxia
Cold

neuronal degeneration

Front 62

How is regeneration limited in the CNS?

Back 62

Oligodendrocytes inhibit neurite outgrowth

Reactive astrocytes cause glial scarring which interferes with nerve regrowth

Fewer chemotropic factors available in CNS

Front 63

What is wallerian degenration?

Back 63

Axonal degeneration distal to insult
Nerve terminal fills with clumps of
Neurofilaments and disrupted mitochondria
Contact Post synaptic membrane lost
Glia invade and phagocytose debris

Front 64

What are the steps of distal degneration?

Back 64

Synaptic transmission lost, terminal fills with clumps of NFs, disrupted mitochondria (Week 1)
Contact with post-synaptic membrane lost, glial cells invade, axon segment distal to injury withdraws (Week 2)
Distal segment fully degenerates, myelin sheath lost, termed Wallerian degeneration (PNS: week 2-8; CNS, phagocytosis may last for months)

Front 65

Why does retrograde degeneration occur?

Back 65

synaptic pattern dies

Front 66

What happens to a neuron during chromatolysis?

Back 66

Rearrangement of Nissl substance (arrow)
Swelling of the cell body with displacement of the nucleus (arrowhead) (Nissl, ×250)

Front 67

How do Schwann cells promote regeneration?

Back 67

release of trophic factors

Front 68

What is the cause of crocodile tears syndrome?

Back 68

Regrowing axons are not very selective and aberrant
reinervation commonly occurs

Front 69

where are neural stem cells found?

Back 69

walls of the
ventricles

Front 70

How does the CNS compensate for degeneration?

Back 70

Reorganization of neuronal circuits,
Increase spine density,
Dendritic arborization and by
Synaptogenesis

Front 71

What are the consequences of degeneration?

Back 71

Synaptic transmission is lost
Contact post synaptic membrane lost
Nerve terminal fills up with neurofilaments
and disrupted mitochondria
Distal segment degenerates fully, myelin
sheath lost, termed Wallerian degeneration
Glia invade and phagocytose debris (PNS:
week 2-8; CNS, phagocytosis may last months)

Front 72

What are the 5 basic steps of neuron transmission?

Back 72

Synthesis of NT
Packaging (concentration of NT) in presynaptic terminal
Release NT from presynaptic terminal into synapse
Binding of NT to receptor in postsynaptic membrane
Termination of NT action

Front 73

What is vasogenic edema? What is it caused by? What is cytotoxic edema? What is it caused by?

Back 73

Vasogenic edema – fluid leaks from blood vessels into brain
Cause: frequent in cases of head trauma and meningitis
Where: In regions bordering ischemic zones,
Why: increased permeability of the blood-brain barrier

Cytotoxic edema - fluid leaks into individual
neurons
Cause: drug poisoning, water intoxication, hypoxia from asphyxia and acute hyponatremia

Result: shift of water from extracellular space to interior of brain cells