Neuroscience

Question 1

what is parenchyma?

Answer 1

functional neural tissue

Neurons and Glia

Question 2

what are the directional terms for the brain?

Answer 2

1. rostral = anterior
2. caudal = posterior
3. ventral = inferior
4. dorsal = superior

Question 3

what are the different structures on a neuron?

Answer 3

1. dendrites
2. soma (cell body)
3. axon hillock
4. axon
5. axon terminal
6. synapse

Question 4

where does a neuron receive afferent input?

Answer 4

at the dendrite and soma

mechanical/chemical stimuli open channels on the dendrite and soma to generate a graded potential

Question 5

what types of stimuli can effect a neuron?

Answer 5

1. mechanical (sensor/receptors like stretch receptors = baroreceptors )
2. chemical (neurotransmitters)

Question 6

T/F: a graded potential is always excitatory?

Answer 6

FALSE

can be excitatory, inhibitory, depolarizing, hyperpolarizing

Question 7

define spatial summation

Answer 7

summing of graded potentials from 2 separate inputs/terminals

Question 8

define temporal summation

Answer 8

summing a graded potential from one single terminal/input

ex: very intense stimuli like hitting thumb with hammer

Question 9

what is the axon hillock?

Answer 9

trigger zone for action potential

regin at base of axon connected to soma

Question 10

what are axon terminals?

Answer 10

final destination for the AP traveling down an axon

generally many axon terminals assocaited with a single axon due to collateral and terminal branching

Question 11

T/F: a single AP generated at the axon hillock reaches all axon terminals?

Answer 11

TRUE

Question 12

what are the types of axonal transport?

Answer 12

1. fast anterograde
2. slow anterograde = axioplasmic flow
3. fast retrograde

Question 13

what is fast anterograde axonal transport?

Answer 13

the movement of proteins associated with vesicles from the golgi apparatus in the soma to synaptic terminals

(peptide NT, enzymes, and membrane proteins)

Question 14

what occurs during slow anterograde axonal transport?

Answer 14

movement of solube cytoskeletal, proteins from soma to axon terminals

*stop and go microtubule transport

Question 15

what occurs during fast retrograde axonal transport?

Answer 15

movement of endocytosis vesicles from axon terminals to soma

Nonstop microtubule transport

(recycled membrane, chemical messengers, pathogens)

Question 16

what axon structural factors impact signal conduction velocity?

Answer 16

fiber diameter (bigger = faster)

thickness of myelin (thicker = faster)

Question 17

what are the different conduction velocity classifications of axons?

Answer 17

Type A, B, C from fastest to slowest

Question 18

what are the different fiber diameter classifications for axons?

Answer 18

Type I, II, III, IV from biggest to smallest

Question 19

What are the different functional types of neurons?

Answer 19

1. Sensory - carry afferent signals from sensory/receptors to CNS (brain and spinal cord)
2. Motor - carry efferent signals to effectos (muscles and glands)

Question 20

what are the subtypes of sensory neurons?

Answer 20

1. special sensory
2. viscerosensory
3. somatosensory

Question 21

what are the special senses?

Answer 21

1. vision
2. auditory
3. equilibrium
4. olfaction
5. gustatory

Question 22

what are viscerosensory neurons?

Answer 22

single neurons from interoreceptors to subcortical CNS

relfexes that maintain homeostasis (BP, temp)

Question 23

what are somatosensory neurons?

Answer 23

single neuron from skin, muscle, and joint receptors to cortex

touch, pressure, pain, proprioception, tempature (highly localized)

Question 24

which sensory neuron is unconscious?

Answer 24

viscerosensory

Question 25

what are the subtypes of motor neurons?

Answer 25

1. somatomotor
2. autonomic motor

Question 26

which motor neuron subtype is a single neuron pathway and generally under conscious control?

Answer 26

somatomotor

Question 27

T/F: Autonomic motor neurons are 2 neuron pathways

Answer 27

TRUE

involuntary and run from CNS to smooth muscle, cardiac muscle or glands

Question 28

what are the differnet types of autonomic motor neurons?

Answer 28

1. sympathetic
2. parasympathetic
3. associative (interneuron)

Question 29

What are the different types of structural neurons?

Answer 29

1. multipolar
2. bipolar
3. pseudo-unipolar

Question 30

what are multipolar neurons?

Answer 30

soma with a single axon and multiple dendrites

common in CNS

Question 31

what are bipolar neurons?

Answer 31

soma with a single axon and single dendrite stalk

common in special sensory organs

Question 32

what are pseudo-unipolar neurons?

Answer 32

single axon with a proximal (efferent) and distal (afferent) branch

found in sensory neurons of dorsal root ganglion (soma for this neuron)

Question 33

describe the components/make-up of a pseudo-unipoalr neuron

Answer 33

1. proximal branch - CNS to soma
2. soma/cell body - dorsal root ganglion
3. distal branch - dendrite end to the soma

Question 34

describe the structures in a negative feedback neuron loop

Answer 34

1. sensor/receptor
2. sensory neuron
3. control center (brain/spinal cord)
4. motor neuron
5. effector: muscle or gland

Question 35

what are the different classifications of neuron circuits?

Answer 35

1. diverging
2. converging
3. reverberating
4. parallel after discharge

Question 36

what is the function of glial cells?

Answer 36

support neurons

typically 10 glia for every neuron

Question 37

what does a diverging neural circuit do?

Answer 37

allows amplification or mass activation of many targets

Question 38

what does a converging neural circuit do?

Answer 38

increase stimulation or inhibition of postsynaptic neuron

Question 39

what is a reverberating neuron circuit do?

Answer 39

allows circular, self stimulation perpetuation of signal (essentially creating a tone)

Question 40

what are parallel after discharge neuron circuits?

Answer 40

they diverge then converge to increase the frequency of output

Question 41

what are the types of glia in the CNS?

Answer 41

1. astrocytes
2. oligodendrocytes
3. microglial
4. ependymal cells

Question 42

what is the function of astrocytes?

Answer 42

provide support:

1. physically (hold neuron in place)
2. protective
3. nutritional
4. regulation of intracellular Ca2+
5. NT regulation and uptake at synapse
6. blood brain barrier
7. tissue repair of CNS lesion

Question 43

what is the role of oligodendrocytes?

Answer 43

form myelin sheaths in CNS (white matter)

Question 44

what do microglia do?

Answer 44

phagocytosis

Question 45

what are ependymal cells?

Answer 45

line ventricles and central canal facilitating exchange between CSF and interstitial fluid of brain

they are ciliated to facilitate flow of CSF

Question 46

what is CSF?

Answer 46

cerebrospinal fluid

a blood plasma filtrate

Question 47

what produces CSF?

Answer 47

choroidal epithelial cells - cover capillary tufts of choroid plexus; forms a unit with endothelial cells of choroid plexus

Question 48

what are the different types of glial cells in the PNS?

Answer 48

1. Schwann cells
2. satellite cells

Question 49

what do Schwann cells do?

Answer 49

form myelin sheaths in PNS

Question 50

what are the structural layers of a nerve?

Answer 50

1. fiber = singel cell
2. endoneurium = CT covering of a fiber
3. fascicle = bundle of fibers
4. perineurium = CT covering of a fascicle
5. whole nerve = bundle of fascicles
6. epineurium = CT covering of whole nerve

Question 51

describe the different section of a spinal nerve and what type of neurons are found there

Answer 51

1. horns
2. roots
3. rami

Question 52

what are rami communicants?

Answer 52

connect ventral rami to:

1. paravertebral ganglia
2. prevertebral ganglia

Question 53

what are dermatomes?

Answer 53

a region of skin whose somatosensory signals are carried by a particular spinal nerve

Question 54

what are myotomes?

Answer 54

all muscles innervated by a particualr spinal nerve

Question 55

what pneumotic device is used to remember the cranial nerves?

Answer 55

Oh Oh Oh To Touch And Feel Very Good Velvet Such Heaven

Question 56

what pneumotic device is used to remember the function of the cranial nerves?

Answer 56

Some Say Marry Money But My Brother Says Big Brains Matter More

S = sensory

M = motor

B = both

Question 57

what are meninges?

Answer 57

connective tissue coverings encircling the brain and spinal cord

organized in a -tissue, fluid, tissue, fluid, tissue- arrangement

Question 58

what are the3 CT layers in the meninges?

Answer 58

1. Dura mater
2. Arachnoid mater
3. Pia mater

Question 59

where is CSF found?

Answer 59

subarachnoid space

Question 60

What is the role of CSF?

Answer 60

forms a protective cushion and buoys the brain and spinal cord

Question 61

how is CSF produced?

Answer 61

mostly by filtration of blood plasma through specialized capillaries called choroid plexuses which have an outer covering of ependymal cells that contribute to the blood brain barrier.

Question 62

where are choroid plexi located?

Answer 62

all 4 ventricles

Question 63

List the 4 ventricles

Answer 63

1. R/L ventricles (lateral ventricles)
   
   1. R/L hemisphere in all 4 lobes
2. 3rd ventricle
   
   1. between hemispheres at level of thalamus hypothalamuc (diencephalon)
3. 4th ventricle
   
   1. brain stem at level of pons/cerebellum and upper medulla

*all are interconnected

Question 64

what is the foramen of Monroe?

Answer 64

also called interventricular foramen

connects lateral ventricles to 3rd ventricles

Question 65

what is the cerebral aqueduct of Sylvius?

Answer 65

connects 3rd ventricle to 4th ventricle

Question 66

what connects the 4th ventricle to the subarachnoid space?

Answer 66

1. foramena of Lushka - 2 lateral apetures
2. foramen of Magendie - single medial aperture

Question 67

what does the blood brain barrier block?

Answer 67

exchange of hydrophilic substances

Question 68

what does the blood brain barrier consist of?

Answer 68

1. continuous capillar endothelium with tight junctions
2. thick basement membrane
3. covering of astrocytes

Question 69

which organs do not have a blood brain barrier?

Answer 69

circumventricular organs:

hypothalamus

pituitary

pineal gland

Question 70

why do circumventricular organs not have a blood brain barrier?

Answer 70

in order to monitor chemical composition of blood

Question 71

what are the different causes of an axonal injury in the PNS?

Answer 71

1. Stretch
2. Crush
3. Shear
4. Laceration

Question 72

what are the 2 ways axons in the PNS will regrow?

Answer 72

1. axonal sprouting
   
   1. collateral
   2. regenerative

Question 73

what are the steps in axonal regeneration following injury in the PNS?

Answer 73

1. injury to peripheral nerve
2. macrophages rapidly remove myelin debris
3. expression of growth-related factors
4. axon regrowth

Question 74

what are the causes of axonal injury in the CNS?

Answer 74

1. trauma
2. decreased blood flow (ischemia)
3. neurodegenerative disease

Question 75

T/F: CNS axons can regrow after injury

Answer 75

FALSE
typically cannot, instead the brain creates new pathways to compensate for axons lost

Question 76

what doesn’t the CNS regenerate axons?

Answer 76

1. CNS damage triggers necrosis and apoptotic cell death of severed axons
2. Clean up is slow
3. CNS environment is hostile to regenerative attempts
   
   1. astrocytes - glial scarring
   2. microglial activation

Question 77

what is glial scarring?

Answer 77

astrocytes enter injuried area and form a scar to block the apoptosis and further damage → problem with this is that it is a physical blockade/scar which blocs future attempts for regrowth of that axon

Question 78

what is the significance of microglial activation following CNS axonal damage?

Answer 78

microglial cells clear out debris from damage, but cannot differeniate between good and bad cells which ends up cleaning out more than they should

Question 79

T/F: there is a low level of glial cells that can proliferate throughout our lifetime

Answer 79

TRUE

Question 80

what are two areas in the brain that are an exception to the regeneration rule?

Answer 80

1. olfactory bulb
2. hippocampus

Question 81

define neuroplasticity

Answer 81

the ability of the nervous system to reorganize its structure, function and connections in response to injury or the environment, in support of learning, or in relation to therapy

Question 82

What are the neuroplasticity mechanisms based off of effect size?

Answer 82

1. chemical
   
   • short term memory
2. structural
   
   • strong sustained exposure to activities resulting in structural changes
3. functional
   
   • when sufficientyly stimulated, neurons can adopt new function and pass new info along (cortical remapping)

Question 83

what is synaptic pruning?

Answer 83

the ability to pick up on what is important and what is not important

prioritize the pathways that stay “open” and running

Question 84

what are the 2 neuroplasticity mechanisms, based off of how the brain responses to a stimulus?

Answer 84

1. Habituation
2. Learning and memory

Question 85

what is habituation?

Answer 85

a decrease in response to a repeated, benign stimulus

allows us to tune out non-important stimuli and focus on important stimuli

Question 86

what short term habituation

Answer 86

1. short term
   
   • stimulus given around 30 minutes → tends to be transient
   • presynaptic in nature → presynaptic neuron will dump less NT into the synaptic cleft which will blunt the reponse

Question 87

what is long-term habituation?

Answer 87

1. long term
   
   • over an hour
   • postsynaptic changes observed → changes in receptors and proteins being synthesized, tend to be more long lasting changes

Question 88

what are the different types of learning and memory development?

Answer 88

1. Experience-dependent plasticity
2. long-term potentiation and depression

Question 89

what is Long-term potentiation (LTP)?

Answer 89

process by which the synaptic connections between neurons become stronger by frequent activation

requires high intensity stimulation

Question 90

which does LTP require a high intensity stimulation?

Answer 90

1. it will alloow more glutamate to be dumped into synaptic cleft
2. more Na enters the cell
3. results in a larger depolarization event
4. this repels Mg out of the NMDA channel (electrostatic repulsion)
5. Ca can now move into the cell and act as a secondary messenger
6. this results in an increase in structural changes to the postsynaptic cell
   
   • increased in AMPA receptors (Na channel)
   • growth factors = creation of more synapses = cortical remapping

Question 91

what is long-term depression (LTD)?

Answer 91

conversino of active synapses into silent ones

“reset button”

low-intensity, prolonged stimulation required

Question 92

what are the 10 principles of Neuroplasticity?

Answer 92

1. Use it or Lose it
2. Use it and Improve it
3. Specificity matters
4. repetition matters
5. intensity matters
6. time matters
7. salience matters
8. age matters
9. transference or generalization
10. interference

Question 93

what is CINT?

Answer 93

constraint induced movement therapy → restraining the strong arm following a stroke for 23 out of 24 hours of the day, forces pt to use their paralytic arm

Question 94

what is the brain made up of?

Answer 94

over 100 billion neurons (mostly inter-neurons = associative) and 1 trillion neuroglia

Question 95

what are the 5 vesicles of the brain?

Answer 95

1. Telencephalon
2. Diencephalon
3. Mesencephalon (midbrain)
4. Metencephalon
5. Myelencephalon

Question 96

what parts of the brain are in the Telencephalon?

Answer 96

1. Cerebral hemispheres
2. basal ganglia
3. limbic system

Question 97

what parts of the brain are in the Diencephalon?

Answer 97

1. thalamus
2. hypothalamus
3. epithalamus

Question 98

What parts of the brain are in the Mesencephalon (midbrain)?

Answer 98

1. cerebral peduncle
2. corpus quadrigemina
   
   1. Superior colliculi
   2. inferior colliculi
3. CN3 and CN4 nucleus
4. Red nucleus
5. Substantia nigra

Question 99

what parts of the brain are in the Metencephalon?

Answer 99

Pons

Question 100

what parts of the brain are in the Myelencephalon?

Answer 100

1. Medulla oblongata

Question 101

what are the components of the brain stem?

Answer 101

1. medulla oblongata
2. pons
3. midbrain (mesencephalon)

Mesencephalon, Metencephalon and Myelencephalon

Question 102

what does SCALP stand for?

Answer 102

skin

connective tissue

aponeurosis

lipid

periosteum

*protective coverings of the brain

Question 103

what are the protective coverings of the brain?

Answer 103

1. cranial bones (skull)
2. epidural space with fat
3. dura mater
4. subdural space w/interstitial fluid
5. arachnoid mater
6. subarachnoid space w/CSF
7. pia mater

Question 104

name the folds of dura mater that hold the brain in place

Answer 104

1. falx cerebri
2. falx cerebelli
3. tentorium cerebelli

Question 105

what is the falx cerebri?

Answer 105

a sagittal fold between cerebral hemispheres

Question 106

what is the falx cerebelli?

Answer 106

a sagittal fold between cerebellar hemispheres

Question 107

what is the tentorium cerebelli?

Answer 107

a transverse fold between cerebrum and cerebellum

Question 108

what are the 3 components of the blood brain barrier?

Answer 108

1. tight junctions between blood vessel endothelial cells
2. continuous endothelial cell basement membrane
3. astrocytes wrapped around the endothelial cell basement membrane

Question 109

T/F: the BBB allows free passage of hydrophillic substance into the brain?

Answer 109

FALSE

allow free passage of lipid soluble, hydrophobic substances

Question 110

what are the components of the medulla oblongata?

Answer 110

1. nerve tracts (both sensory ascending and motor descending)
2. pyramids
3. decussation of pyramids
4. olives
5. dorsal medulla
   
   • fasciculus gracilis
   • fasiculus cuneatus
6. decussation of the medial lemniscus
7. nuclei
8. cranial nerve nuclei for CN, 8 - 12

Question 111

what is the overall function of the brain stem?

Answer 111

1. contains nuclei for vital centers and cranial nerves
2. signal propagation via ascending (sensory signals) and descending (motor signals) tracts

Question 112

what are the pyramids in the medulla oblongata?

Answer 112

paried ventral surface ridges that contain motor descending tracts

Question 113

what are the decussation of pyramids?

Answer 113

where motor tracts from R/L brain cross to control muscles on the opposite side

Question 114

what are the olives in the medulla oblongata?

Answer 114

paired bulges lateral to pyramids which contain the inferior olivary nuclei

these link the brain and spinal cord motor signals to the cerebellum for perception of time

Question 115

what do the fasciculus gracilis and cuneatus do?

Answer 115

relay sensory ascending input to the opposite side of the brain

Question 116

what is the decussation of the medial lemniscus?

Answer 116

crossover of ascending sensory input to the contralateral brain hemisphere

Question 117

What is contained within the Pons?

Answer 117

1. cranial nerve nuclei for CN 5, 6, and 7
2. ascending and descending tracts

Question 118

what is the function of the Pons?

Answer 118

information relay for cerebellar hemmispheres

Question 119

what is located in the midbrain?

Answer 119

1. cerebral peduncles
2. corpora quadrigemina
3. cranial nerve nuclei for CN 3, 4
4. red nucleus and substantia nigra

Question 120

what are the cerebral peduncles?

Answer 120

they contain descending motor axaon tracts from cerebral hemispheres to spinal cord, medulla, and pons

and

ascending sensory axons going to the cerebrum

Question 121

what is the corpora quadrigemina made up of?

Answer 121

1. superior colliculi
2. inferior colliculi

Question 122

what does the superior colliculi control?

Answer 122

reflex movement of eye, head, and neck to visual and other stimuli

Question 123

what do the inferior colliculi control?

Answer 123

reflex movement of head and neck to auditory stimuli

Question 124

what is the function of the red nucleus and substantia nigra?

Answer 124

modify motor signals

Question 125

what is the overall function of the midbrain?

Answer 125

1. relay motor impulses from cerebral cortex
2. relay sensory impulses from spinal cord to thalamus

Question 126

what is the reticular formation?

Answer 126

a diffuse structure, composed of areas of gray matter interspersed among areas of white matter in central portions of the Diencephalon, brain stem, and spinal cord

Question 127

what is the function of the reticular formation?

Answer 127

1. alerting cerebral cortex to sensory signals
2. reticular activating system → functions in maintaining consciousness and awakening from sleep by stimulating the cortex
3. filter sensory input to remove unimportant input (prevents sensory overload)
4. efferent motor function in maintaining muscle tone

Question 128

what is the cerebellum (metencephalon) comprised of?

Answer 128

1. vermis (worm)
2. cerebellar hemispheres
3. peduncles

Question 129

describe the cross section anatomy of the cerebellum

Answer 129

1. cortex = gray matter
2. folia ridges
3. arbor vitae (nerve tracts = white matter)
4. cerebellar nuclei

Question 130

what is the function of the cerebellum?

Answer 130

1. smooth and coordinate (refine) cerebral control of skeletal muscle movements to facilitate complex muscle activity
2. regulate muscle tone
3. posture and balance

Question 131

what makes up the Diencephalon?

Answer 131

1. thalamus
2. hypothalamus
3. epithalamus
4. subthalamus

Question 132

describe the structure of the thalamus

Answer 132

composed of paired masses of mixed gray (nuclei) and white (tracts) matter that are connected by intermediate mass (crossover point)

Question 133

what is the function of the thalamus?

Answer 133

1. relay sensory info to correct region of cerebral cortex
2. refine motor signals with the basal nucleus

Question 134

describe the composition of the hypothalamus

Answer 134

composed of:

1. dozen nuclei
2. mammillary bodies (visible on inferior surface)
3. infundibulum (connects pituitary to the hypothalamus)

Question 135

what is the overall function of the hypothalamus?

Answer 135

control of body activities to maintain homeostasis

Question 136

T/F: the hypothalamus is a circumventricular organ?

Answer 136

TRUE

Question 137

what are the specific functions of the hypothalamus?

Answer 137

1. control of ANS: heart, gut, bladder
2. control of endocrine system via control of the pituitary gland
3. regulates emotional behavior (part of limbic system)
4. regulates eating and drinking
5. control body temp
6. regulates circadian rhtyhms and states of consciousness

Question 138

describe the structure of the epithalamus

Answer 138

composed of:

1. pineal gland
2. habenular nuclei (paired structure)

Question 139

what is the function of the epithalamus?

Answer 139

more of a modulator

functions in:

1. melatonin production (at pineal gland)
2. habenular nuclei involved in the emotional response to smell

Question 140

what is the subthalamus composed of?

Answer 140

1. subthalamic nuclei (paired)
2. parts of red nuclei (paired)
3. parts of substantia nigra (paired)

Question 141

what is the function of the subthalamus?

Answer 141

connects to cerebellum and motor cortex for control of body movement

Question 142

what are circumventricular organs?

Answer 142

areas of the brain that do not have a BBB, therefore they are able to monitor chemical changes in the blood

tend to be endocrine organs

Question 143

where are circumventricular organs found?

Answer 143

1. hypothalamus
2. pineal
3. pituitary (hypophysis)

Question 144

what region of the brain are the basal ganglia in?

Answer 144

Telencephalon

Question 145

what are the basal ganglia?

Answer 145

consist of paired nuclei (gray matter)

function in control of skeletal muscle movement and muscle tone. Refine movement from uncoordinated jerky motion to smooth motion

Question 146

what region of the brain is the limbic system in?

Answer 146

Telencephalon

Diencephalon

Question 147

what is the limbic system comprised of?

Answer 147

1. paired nuclei
2. tracts
3. cortex (parts of frontal, parietal, and temporal lobes)

Question 148

what is the function of the limbic system?

Answer 148

“primitive brain” function in emotion aspects of behavior and memory-pain, pleasure, affection, and anger → to determine feelings

Question 149

What portion of the brain is the cerebrum in?

Answer 149

Telencephalon

Question 150

describe the composition of the cerebrum

Answer 150

1. cerebral cortex (gray matter)
2. cerebral white matter

Question 151

what is cerebral cortex (gray matter)?

Answer 151

10s of billions of associate (inter) neurons

typically arranged in 6 layers to allow vertical integration

Question 152

what is cerebral white matter made of?

Answer 152

3 types of neurons:

1. association fibers
2. commissural fibers
3. projection fibers

Question 153

what do association fibers in the cerebral white matter do?

Answer 153

connect different gyri in same hemisphere

Question 154

what do commissural fibers in cerebral white matter do?

Answer 154

connect different gyri in opposite hemisphere (found in corpus collosum)

Question 155

what do projection fibers in the cerebral white matter do?

Answer 155

connect the cerebrum to rest of body (sensory and motor tracts)

Question 156

Cerebrum is the highest of the brain regions, what are it’s functions?

Answer 156

1. conscious sensation
2. voluntary motor activity
3. higher brain functions
   
   • cognition
   • association of sensory input with memory to produce more memory
   • language
   • astract though

Question 157

describe the surface anatomy of the cerebrum

Answer 157

1. gryi = ridges
2. sulci = shallow grooves
3. fissures = deep grooves
4. longitudinal fissures = separate R/L hemispheres
5. hemispheres = R/L side of cerebru
6. corpus callosum
7. lobes
8. central sulcus
9. precentral gyrus
10. lateral cerebral fissure (sulcus)
11. parieto-occipital sulcus)

Question 158

what is the corpos callosum?

Answer 158

large collection of commissural tracts connecting R/L hemispheres

Question 159

what is the central sulcus of the cerebrum?

Answer 159

separates frontal and parietal lobes

Question 160

what is the precentral gyrus of the cerebrum?

Answer 160

anterior to central sulcus

voluntary (somato-) motor area

Question 161

what is the postcentral gyrus of the cerebrum?

Answer 161

posterior to central sulcus

conscious (somato-) sensory area

Question 162

what is the lateral cerebral fissure (sulcus) of the cerebrum?

Answer 162

separates frontal and temporal lobes

Question 163

what is the parieto-occipital sulcus of the cerebrum?

Answer 163

separates parietal and occiptal lobes

Question 164

Name the Lobes of the cerebrum

Answer 164

1. Frontal
2. Parietal
3. Temporal
4. Occipital
5. Insula

Question 165

where is the frontal lobe?

Answer 165

anterior of central sulcus and medial to lateral sulcus

Question 166

what are the different sections of the frontal lobe?

Answer 166

1. precentral gyrus
2. premotor area (supplemental motor area)
3. frontal eye field
4. Broca’s area
5. prefrontal cortex
6. cingulate gyrus

Question 167

what are the components of the precentral gyrus?

Answer 167

1. primary motor cortex
   
   1. somatotopic
   2. homunculus

Question 168

what does the primary motor cortex do?

Answer 168

control voluntary movement on contralateral side of the body

Question 169

what does the term somatotopic mean?

Answer 169

refers to specific regions of the precentral gyrus that control muscles in specific body regions

Question 170

what is a homunculus?

Answer 170

it depicts somatotopic organization of precentral gyrus and relative cortical contributions to a particular body region

Question 171

what is the premotor area (supplemental motor area) of the frontal lobe?

Answer 171

associative area next to precentral gyrus functions to initiate and sequence motor activity

Question 172

what is the function of the frontal eye field of the Frontal lobe?

Answer 172

coordinated R and L eye movement = conjugate eye movements

Question 173

What is Broac’s area on the Frontal Lobe?

Answer 173

on L hemisphere only

coordinates motor speech

Question 174

where is the prefrontal cortex?

Answer 174

rostral most part of the frontal lobe

primary target of lobotomy

Question 175

significance of the prefontal cortex?

Answer 175

input from all regions of cortex and limbic system

output to wide variety ⇒ subcortical nuclei-thalamus, basal ganglia, brain stem

functions to regulate visceral, emotional, and cognitive processes

Question 176

what is the cingulate gyrus of the frontal lobe?

Answer 176

medial surface (within longitudinal fissure) of frontal and parietal lobes

limbic cortex for emotional behavior, autonomic reponse, and learning

Question 177

where is the Insula lobe located?

Answer 177

within the lateral sulcus where frontal, parietal and temporal lobes come together

Question 178

what is the function of the Insula Lobe?

Answer 178

integration of sensory input for:

1. taste and olfaction
2. viscerosensation (interoreceptors)
3. pain

Question 179

what are the sections of the Parietal Lobe?

Answer 179

1. post central gyrus
2. supramarginal and angular gyrus
3. Wernicke’s area
4. superior parietal lobe

Question 180

what part of the Parietal Lobe is located at the post central gyrus?

Answer 180

Somatosensory Cortex

primary sensory area for tactile and proprioceptive sensation → end destination for conscious somatosensory signals

Question 181

what does the supramarginal and angular gyrus do?

Answer 181

receive visual and auditory input for perceptional discrimination and integration

Question 182

where is Wernicke’s area and what does it do?

Answer 182

located in both parietal and temporal lobes of the Left hemisphere

functions in comprehension of spoken language and works with Broca’s area to formulate a verbal reponse

Question 183

what is the superior parietal lobe?

Answer 183

an association area integrating sensory and motor areas to program complex motor responses

Question 184

where is the occipital lobe of the cerebrum located?

Answer 184

caudal to the parietal-occipital sulcus on the medial border

Question 185

what is located in the occipital lobe?

Answer 185

primary visual cortex

visual association cortex

Question 186

name the structures at the temporal lobe

Answer 186

1. primary auditory cortex
2. superior temporal gyrus
3. middle temporal gyrus
4. inferior temporal gyrus
5. parahippocampal gyrus and uncus

Question 187

where is the primary auditory cortex located?

Answer 187

medial aspect of superior temporal gyrus → transverse gyri Heschl

Question 188

what is located at the superior temporal gyrus?

Answer 188

auditory association cortex

Question 189

what is the function of the middle temporal gyrus?

Answer 189

perception and analysis of motion in the visual field

Question 190

what is the function of the inferior temporal gyrus?

Answer 190

facial recognition in response to visual input

Question 191

where is the parahippocampal gyrus and uncus and what is it’s function?

Answer 191

located on the inferior surface of temporal lobe

function w/limbic system

Question 192

how are hemispheres in the cerebrum divided?

Answer 192

separated by longitudinal fissure and connected by commissural fibers

Question 193

what is hemispheric localization?

Answer 193

refers to the functional differences that exist between hemispheres = cerebral dominance

Question 194

what is the left hemisphere primarily responsible for?

Answer 194

1. language interpretation and execution
2. numerical and scientific skills (abstract)
3. reasoning

Question 195

what is the right hemisphere primarily responsible for?

Answer 195

1. musical, artistic
2. special pattern interpretation
3. facial recognition
4. emotional content of language
5. mental images of visual, auditory, somatic, taste, olfactory input

Question 196

what is cerebral dominance due to?

Answer 196

1. unequal cortical representation of function in homologous regions of the 2 hemispheres
2. diminished commissural cross connection between the regions
   
   • visual cortex → temporal eye field is uncrossed
   • primary motor and sensory areas of distal arm and leg

Question 197

describe the course of the internal carotid through the skull

Answer 197

1. external opening of carotid canal
2. carotid canal (petrous part of temporal bone)
3. internal opening of carotid canal
4. crosses over foramen lacerum
5. runs along base of sella turcica in carotid groove
6. joins the optic nerve at prechiasmatic groove

Question 198

what are the branches of the internal carotids proximal to distal?

Answer 198

1. opthalmic
2. posterior communicating
3. anterior choroidal artery
4. anterior cerebral artery
5. middle cerebral artery

Question 199

where does the opthamic artery run?

Answer 199

with CN2 supplying blood to the choroid/retina of the eye

via central artery of the retina

Question 200

what does the posterior communicating artery connect the internal carotid to?

Answer 200

Circle of Willis

Question 201

what does the posterior communicating artery eventually supply?

Answer 201

Circle of Willis which supplies:

1. diencephalon
   
   1. pituitary
   2. infundibulum
   3. hypothalamus
   4. thalamus

Question 202

where is the anterior choroidal artery and what does it supply?

Answer 202

arises near middle cerebral artery

supplies choroid plexus of lateral ventricles, optic tract, internal capsule, globus pallidus (basal nucleus)

*supplies deep structures of telencephalon

Question 203

where does the anterior cerebral artery run?

Answer 203

runs in longitudinal fissure above corpus callosum to medial aspect of frontal and parietal lobes

Question 204

what is the anterior communicating artery?

Answer 204

an anastomosis between R/L anterior cerebral arteries

Question 205

what does the middle cerebral artery supply?

Answer 205

runs in lateral sulcus to:

1. lateral frontal
2. lateral parietal
3. insula
4. lateral occipital
5. M/L temporal
6. sub-cortical deep structures
   
   1. basal ganglia
   2. internal capsule
   3. limbic structures

Question 206

after the vertebrals pass through the foramen magnum where do they head next?

Answer 206

they ascend the clivus and then fuse into basilar artery

Question 207

what are the branches of the vertebral arteries from proximal to distal?

Answer 207

1. anterior spinal artery - medial medulla
2. posterior inferior cerebellar - lateral medulla
3. posterior spinal artery - dorsal medial medulla

Question 208

what are the branches of the basilar artery from proximal to distal?

Answer 208

1. anterior inferior cerebellar
2. labyrinthine arteries
3. pontine arteries
4. superior cerebellar arteries
5. posterior cerebral arteries

Question 209

what does the anterior inferior cerebellar artery supply?

Answer 209

it is a branch of the basilar artery

supplies cerebellum and pons

Question 210

what do the labyrinthine arteries supply?

Answer 210

branch of basilar artery that enters internal acoustic meatus

supplies cochlea and vestibular apparatus

Question 211

what do the pontine arteries supply?

Answer 211

branch of basilar artery

supplies pons

Question 212

what do the superior cerebellar arteries supply?

Answer 212

branch of basilar artery

supplies cerebellum, pons, and midbrain

Question 213

what do the posterior cerebral arteries supply?

Answer 213

branch of basilar artery

supplies cortex (medial and inferior occipital, inferior temporal) and subcortical structures of midbrain, subthalamus, and thalamus

Question 214

what is the Circle of Willis?

Answer 214

an anastomosis between internal carotid arteries and basilar arteries

Question 215

what forms the Circle of Willis?

Answer 215

1. anterior communicating arteries
2. anterior cerebral arteries
3. posterior communcating arteries
4. posterior cerebral arteries

Question 216

what is the dural artery?

Answer 216

middle meningeal from the maxilary artery (from external carotid) via foramen spinosum

Question 217

what is the venous drainage of the brain?

Answer 217

Dural sinuses

Question 218

what is the path of venous blood flow in the brain?

Answer 218

1. superior sagittal sinus, inferior sgittal sinus (to straight sinus) and occipital sinus all drain into:
2. confluence of sinuses
3. transverse sinus
4. superficial veins
5. sigmoid sinus
6. internal jugular vein

Question 219

name the venous plexi in the brain

Answer 219

1. cavernous sinus
2. pterygoid sinus
3. basilar
4. superior and inferior petrosal drain into sinuses or jugular veins

Question 220

Name the grooves in the spinal cord cross section

Answer 220

1. anterior median fissure
2. posterior median sulcus

Question 221

what is gray matter in the spinal cord?

Answer 221

located in an H shaped central core

contains neurons and neuroglial cell bodies as well as unmyelinated neuron processes (axons and dendrites)

Question 222

what are all the gray matter structures within the spinal cord?

Answer 222

1. dorsal horn
2. ventral horn
3. lateral horn
4. rexed’s laminae
5. grey commissure

Question 223

T/F: the ventral horn of the spinal cord is somatotpically organized?

Answer 223

TRUE

Question 224

how is the ventral horn somatopically organized?

Answer 224

1. medial ventral horn → controls axial muscles
2. lateral ventral horn → controls appendicular muscles
3. posterior section of ventral horn → controls flexors
4. anterior section of ventral horn → controls extensors

Question 225

which regions of the spine have lateral horns?

Answer 225

Thoracic, Lumbar and Sacral

T1-L2 = sympathetic preganglionic neurons

S2-S4 = parasympathetic preganglionic neurons

Question 226

What are Rexed’s Laminae?

Answer 226

10 histological/functional regions of gray matter in the dorsal and ventral horns

Question 227

what are the lamina in Rexed’s laminae responsible for?

Answer 227

1. Lamina 1 = marginal layer for noxious stimuli
2. lamina 2 = substatia gelantinosa for noxious stimuli etc.

Question 228

what is the grey commissure in the spinal cord gray matter?

Answer 228

connection between R and L gray matter

allows signals to cross to the opposite side

Question 229

what is located in the white matter of the spinal cord?

Answer 229

ascending (sensory) and descending (motor) tracts (fasiciculi) which are bundles of myelinated axons with a similar origin and terminal destination

Question 230

list the organization of the white matter columns in the spinal cord

Answer 230

1. Dorsal Column = bundle of tracts
2. Lateral Column
   
   1. A/P lateral column
3. Anterior Column
4. Propriospinal = axons that begin and end within the cord providing interconnections between tracts and gray matter for context

Question 231

what is the central canal?

Answer 231

a continuation of the 4th ventrile of the brain, contains CSF

Question 232

what does the term funiculus mean? what about fascicula?

Answer 232

funiculus = column

fascicula = tract

Question 233

what is the function of the spinal cord?

Answer 233

1. propagate nerve impulses between the periphery and the brain
2. somatic reflex control center

Question 234

what is the primary arterial supply to the spinal cord?

Answer 234

1. cervical = spinal branches from vertebral arteries
2. thoracic = spinal branches from posterior intercostal arteries
3. lumbar = spinal branches from lumbar arteries

Question 235

what do the spinal branches of the primary arteries of the spinal cord branch into?

Answer 235

dorsal and ventral segmental arteries

Question 236

what do the dorsal and ventral segmental arteries of the spinal cord form?

Answer 236

1. deep anterior region = anterior spinal artery
2. deep posterior region = 2 posterior spinal arteries
3. superficial regions = A/P radicular

Question 237

List the veins of the spinal cord

Answer 237

1. anterior medial spinal vein
2. anterolateral spinal vein
3. posteromedian spinal vein
4. posterolateral spinal vein

Question 238

What are the 2 types of NT receptors?

Answer 238

1. Ionotropic → ligand-gated ion channels
2. Metabotropic → G-coupled receptors

Question 239

Name some of the more prominent neutrotransmitters

Answer 239

1. Glutamate
2. GABA
3. Glycine
4. Acetylcholine
5. Serotonin
6. Dopamine
7. Norepinephrine

Question 240

T/F: Glutamate is the most abundate NT in our brain and CNS?

Answer 240

TRUE

Question 241

what type of NT is glutamate?

Answer 241

Excitatory post-synaptic response

Question 242

what functions are associated with glutamate?

Answer 242

learning and memory

synaptic plasticity

Question 243

what types of receptors bind glutamate?

Answer 243

1. Ionotropic:
   
   1. NMDA
   2. AMPA
   3. Kainate
2. Metabotropic
   
   1. 3 groups and 8 subgroups
   2. modulate glutamate release
   3. affect postsynaptic excitability

Question 244

T/F: Kinate receptors have both resynaptic and postsynaptic actions?

Answer 244

TRUE

presynaptic: GABA
postsynaptic: Glutamate

Question 245

Name some agonists/antagonists to glutamate

Answer 245

Antagonists:

phencyclidine

Riluzole

Question 246

What are some clinical pathologies assocaited with glutamate?

Answer 246

1. glutamate excitotoxicity
2. schizophrenia
3. epilepsy
4. Alzheimer’s disease

Question 247

what is glutamater excitotoxicity?

Answer 247

increased glutamate → excess intracellular Ca2+ → apoptosis

Question 248

What is the major inhibitory NT in the CNS?

Answer 248

GABA

particularly at interneurons wihtin the spinal cord

Question 249

what is the function of the GABA NT?

Answer 249

1. used in trx of anxiety, reha for drug abuse
2. inhibits motor, sensory, and cognitive neurons
3. sedation, muscular/cardiorespiratory relaxation, pain inhibition

Question 250

What are the receptors for GABA?

Answer 250

Ionotropic: GABA_A

Metabotropic: GABA_B

Question 251

Name some agonists/antagonists to GABA

Answer 251

Agonists:

Alcohol

Benzodiazepines

Barbiturates

Baclofen

Question 252

what are some clinical pathologies that GABA is used in?

Answer 252

Epilepsy trx

Huntington’s disease

Question 253

where is glycine found and what does it do?

Answer 253

brainstem and spinal cord

inhibitory post-synaptic response

functions → inhibits spinal interneurons

Question 254

What are some receptors for Glycine?

Answer 254

Ionotropic: Cl- channel (inhibitory)

Question 255

Name some agonists/antagonists to Glycine

Answer 255

antagonist

Strychnine

Question 256

What are some clinical pathologies that glycine is used in?

Answer 256

spasticity

spinal shock

Question 257

where is ACh found?

Answer 257

widely distributed

in motor neurons, basal ganglia and ANS

found in NMJ

Question 258

what type of NT is ACh?

Answer 258

Excitatory post-synaptic response

Question 259

what is the function of ACh?

Answer 259

1. triggers muscle contraction
2. ANS involvement
3. stimulates excretion of certain hormones
4. in CNS, involved in wakefulness, attentiveness, anger, sexuality, amongst other things

Question 260

T/F: ACh is a major converyer of info in the PNS?

Answer 260

TRUE

Question 261

what are some receptors for ACh?

Answer 261

Ionotropic: nicotinic (excitatory)

Metabotropic: muscarinic (excitatory or inhibitory)

Question 262

Name some agonists/antagonists to ACh

Answer 262

Agonist: Nicotine

Antagonist: Botulinum toxin, Atropine

Question 263

What are some clinical pathologies that ACh is used in the treatment

Answer 263

Alzheimer’s Disease, Dementia

Myasthenia Gravis

Tobacco addiction

Question 264

where is serotonin found?

Answer 264

brain and brainstem (pineal gland, raphe nuclei in pons, limbic system) and GI tract

Question 265

T/F: serotonin is both excitatory and inhibitory postsynaptically?

Answer 265

TRUE

Question 266

what are some functions of serotonin?

Answer 266

1. emotions
2. sleep-wake cycles and other autonomic functions
3. GI tract regulation, appetite
4. cardiovascular growth factor

Question 267

what are some receptors for serotonin?

Answer 267

Ionotropic: 5-HT₃ (excitatory)

Metabotropic: 5-HT_1-7 (excitatory or inhibitory)

Question 268

Name some agonists/antagonists to serotonin

Answer 268

Agonists: SSRIs

Question 269

What are some clinical pathologies that serotonin is used in the treatment?

Answer 269

Depression

OCD

Autism

Serotonin Syndrome

Question 270

Where is dopamine found?

Answer 270

CNS: substantia nigra, midbrain, hypothalamus

ANS: aympathetic neurons

Question 271

T/F: dopamine has both excitatory and inhibitory post-synpatic responses

Answer 271

TRUE

Question 272

what are some functions of dopamine?

Answer 272

1. movement
2. reward
3. memory, attention, motivation
4. and a lot more!

Question 273

what class of NT is dopamine?

Answer 273

Amine

these function as neuromodulators

Question 274

what are some receptors for dopamine?

Answer 274

ionotropic: none

Metabotropic: excitatory and inhibitory

Question 275

Name some agonists/antagonists to dopamine

Answer 275

agonists:

amphetamines

L-dopa

Question 276

what are some clinical pathologies that dopamine is used in the treatment?

Answer 276

Parkinson’s Disease

Schizophrenia

ADHD

Substance dependency

Question 277

where is NE found?

Answer 277

cortex: locus ceruleus (pons) and medulla

ANS: sympathetic neurons

Question 278

what type of NT is NE?

Answer 278

excitatory post synaptic response

*there are some inhibitory responses linked to NE

Question 279

what is the function of NE?

Answer 279

1. plays a vital role in active surveillance by increasing attention to sensory info
2. SNS: essential for “fight or flight” reaction to stress

Question 280

What are some receptors for NE?

Answer 280

Ionotropic: none

Metabotropic: alpha 1 and 2, and beta

Question 281

Name some agonists/antagonists to NE

Answer 281

Antagonist: Beta blocker

Agonist: Amphetamines, Cocaine, TCA

Question 282

what are some clinical pathologies that NE is used to treat?

Answer 282

ADHD

Hypotension

PTSD
Parkinson’s Disease

Question 283

what is located in the inferior cerebellar peduncle?

Answer 283

afferent fibers from spinal cord and medulla to cerebellum

(posterior spinocerebellar tract, cuneocerebellar tract)

Question 284

what general nuclei are located in the medulla?

Answer 284

1. CN 8-12
2. nuclei of vital centers
3. nuclei of reticular formation

Question 285

list the anterior surface anatomy structures of the medulla

Answer 285

1. paired pyramids
2. decussation of pyramids
3. CN 6 - 12 emerging
4. inferior olivary nuclei

Question 286

what are the paired pyramids on the anterior surface of the medulla?

Answer 286

corticospinal tracts

carrying descending somatomotor signals

Question 287

What is the decussation of pyramids on the anterior surface of the medulla?

Answer 287

where the descending corticospinal tracts cross to the opposite side of the body

Question 288

T/F: 75% of the corticospinal tracts from the cerebrum cross at the decussation and form the lateral corticospinal tract?

Answer 288

FALSE

90% do

these mostly supply appendicular muscles

Question 289

what is the medial corticospinal tract?

Answer 289

the remaining 10% of descending corticospinal tracts that do not cross to the opposite side at the decussation of pyramids in the medulla

mostly axial muscles

Question 290

what is the role of the inferior olivary nuclei?

Answer 290

cerebellar relay center for perception of time

Question 291

list the posterior surface anatomy structures of the medulla

Answer 291

1. fasciculata cuneatus
2. fasciculata gracilis
3. tuberculum cuneatus and gracilis
4. nuclei cuneatus and gracilis
5. open part associated w/4th ventricle underlying the cerebellum
6. area postrema

Question 292

what is the area postrema?

Answer 292

floor of 4th ventricle leading to opening of central canal

vomit center

Question 293

list the fiber tracts located at the caudal closed medulla (level of pyramid decussation)

Answer 293

1. pyramids: corticospinal
2. decussation of pyramids
3. fasciculus gracilis
4. fasciculus cuneatus
5. spinothalamic tracts
6. anterior spinocerebellar
7. posterior spinocerebellar
8. CN 5 spinal trigeminal tract

Question 294

what type of information is carried in the pyramids at the medulla?

Answer 294

efferent voluntary from cerebral cortex to muscles of trunk and appendages

Question 295

what type of information is carried in the fasciculus gracilis?

Answer 295

sensory touch and proprioception from the legs

(touch, pressure, pain, etc.)

Question 296

what type of information is carried in the fasciculus cuneatus?

Answer 296

sensory touch and proprioception from the arms

from the brachial plexus (touch, pressure, pain, etc.)

Question 297

what type of information is carried in the spinothalamic tracts?

Answer 297

sensory pain and temperature from trunk and appendages

Question 298

what type of information is carried in the anterior spinocerebellar tract?

Answer 298

sensory info from thoracolumbar ventral horn to cerebellum

Question 299

what type of information is carried in the posterior spinocerebellar tract?

Answer 299

sensory from legs to cerebellum

Question 300

what type of information is carried by the CN 5 spinal trigeminal tract in the medulla?

Answer 300

localized pain from the face/head

Question 301

what nuclei are found in the caudal closed medulla

(level of the pyramid decussation)

Answer 301

spinal trigeminal nucleus CN5 = afferent pain and temp of the head

Question 302

list the fiber tracts found in the rostral closed medulla

(level of decussation of medial lemniscus)

Answer 302

1. decussation of medial lemniscus
2. pyramids
3. CN 5 spinal tract
4. anterior spinocerebellar
5. posterior spinocerebellar
6. spinothalamic tracts
7. medial longitudinal fasciculus

Question 303

what is the decussation of medial lemniscus in the medulla?

Answer 303

crossover point for ascending fibers for proprioception and tactile sensation from the nuceli gracilis and cuneatis (ie. dorsal column tracts)

Question 304

what type of information is carried by the medal longitudinal fasciculus?

(*list tracts and nuclei)

Answer 304

BALANCE

1. afferent ascending sensory from vestibular nuclei
2. descending motor from medial vestibulospinal tract
3. tectospinal tract (head turner)

Question 305

list the nuclei found in the rostral closed medulla

Answer 305

1. nucleus gracilis
2. nucleus cuneatis
3. accessory cuneate nucles
4. spinal trigeminal nucleus CN5
5. reticular formation
6. inferior olivary nuclei
7. nucleus ambiguous

Question 306

what is the accessory cuneate nucleus associated with?

Answer 306

cuneocerebellar tract

(sensory info from arms to cerebellum via inferior cerebellar peduncle)

Question 307

what is the role of the reticular formation?

Answer 307

1. modulates sensory signaling to cortex
2. modulates motor signaling (reticulospinal tracts)
3. autonomic activity
4. sleep/wake
5. emotions

Question 308

what makes up the nucleus ambiguous?

Answer 308

CN9 and 10 (for swallowing)

Question 309

what differentiates the open medulla from the closed medulla?

Answer 309

central canal in the closed medulla is replaced with the 4th ventricle in the open medulla

Question 310

what is the basal plate?

Answer 310

the floor of the 4th ventricle medially

at the open medulla

contains motor nuclei

Question 311

what is the alar plate?

Answer 311

floor of the 4th ventricle laterally

open medulla

contains sensory nuclei

Question 312

list the nuclei found in the basal plate (from medial to lateral)

Answer 312

1. hypoglossal nuclei (CN 12)
2. nucleus ambiguus (CN 9 and 10)
3. dorsal motor nucleus (CN 10 = PNS)
4. inferior salivatory nucleus (CN9 to parotid)

Question 313

what does the hypoglossal nucleus in the basal plate contain?

Answer 313

somatomotor to skeletal muscle of tongue

Question 314

what does the nucleus ambiguus at the basal plate do?

Answer 314

contain special visceral efferent to skeletal muscles of larynx and pharynx for swallowing

Question 315

list the nuclei found in the alar plate of the open medulla (moving medially to laterally)

Answer 315

1. solitary nucleus (CN 7, 9, 10)
2. spinal nucleus of CN 5
3. vestibular nuclei of CN 8 (inferior and medial)
4. cochlear nucleus of CN 8

Question 316

what is role of the solitary nucleus in the alar plate?

Answer 316

1. viscerosensory from CN 9 and 10 for cardiovascular and respiratory input
2. special sensory for taste (CN 7, 9, 10)

Question 317

what does the spinal nucleus of CN 5 in the alar plate contain?

Answer 317

general somatic afferent for somatosensory (pain and temp) of head

Question 318

what does the vestibular nuclei of CN 8 (inferior and medial) in the alar contain?

Answer 318

special sensory afferent for balance

Question 319

what does the cochlear nuclei of CN 8 in the alar plate do?

Answer 319

special sensory afferent for auditory

Question 320

What fiber tracts are found in the open medulla?

Answer 320

1. inferior cerebellar peduncle
2. medial longitudinal fasciculus with tectospinal tract
3. medial lemniscus
4. spinothalamic tract
5. pyramids (corticospinal tract)

Question 321

what type of info does the inferior cerebellar peduncle carry?

Answer 321

afferent sensory from arms and legs to cerebellum

Question 322

what is the function of the medial longitudinal fasciculus and the tectospinal tract?

Answer 322

coordinates movements of eyes and body with vestibular input for overall balance/equilibrium

Question 323

what nuclei are not found in the alar and basal plate of the open medulla?

Answer 323

1. reticular formation
2. inferior olivary nuclei

Question 324

describe the gross anatomy of the pons

Answer 324

1. basilar pons = ventral surface
2. pontine tegmentum = dorsal surface and floor of 4th ventricle

Question 325

where are ascending sensory tracts generally found in the pons?

Answer 325

tegmental area (dorsal surface)

Question 326

where are descending motor tracts generally found in the pons?

Answer 326

basilar area (ventral surface)

Question 327

list the fiber tracts that are found in the basilar pons

Answer 327

1. transverse pontine (pontocerebellar)
2. corticospinal fiber tract
3. corticobulbar fiber tract

Question 328

what type of info is carried by the transverse pontine (pontocerebellar) tract?

Answer 328

relayed afferent signals to cerebellum via middle cerebellar peduncle

Question 329

what type of fibers is the transverse pontine (pontocerebellar) tract made up of?

Answer 329

commissural and afferent fibers

Question 330

where are the corticospinal and corticobulbar fiber tracts?

Answer 330

run longitudinally through basilar pons

Question 331

what type of info is carried by the corticobulbar tract?

Answer 331

somatomotor from precentral gyrus to the head

Question 332

what type of info is carried by the corticospinal tract?

Answer 332

somatomotor from precentral gyrus prior to decussation of pyramids heading to the body

Question 333

what nuclei are found in the basilar pons?

Answer 333

deep pontine nuclei

Question 334

list the fiber tracts that are found in the tegmental pons

Answer 334

1. facial colliculus
2. S/M/I cerebellar peduncle
3. medial lemniscus
4. medial longitudinal fasciculus
5. spinothalamic
6. trigeminothalamic
7. lateral lemniscus
8. rubrospinal tract
9. tectospinal tract
10. spinal nucleus tract of CN 5
11. descending limbic and hypothalamic fibers

Question 335

what type of info is carried by the facial colliculus

Answer 335

facial nerve CN7 fibers

Question 336

what type of info is carried by the superior cerebellar peduncle?

Answer 336

efferent fibers from cerebellum to brain stem and cortex

Question 337

what type of info is carried by the middle cerebellar peduncle?

Answer 337

afferent fibers from cortex to cerebellum

Question 338

what type of info is carried by the inferior cerebellar peduncle?

Answer 338

afferent fibers from medulla and spinal cord to cerebellum

Question 339

what type of info is carried by the medial lemniscus at the level of the tegmental pons?

Answer 339

touch, pressure and proprioception from the entire body ascending to the cortex

Question 340

what type of info is carried by the spinothalamic tract in the tegmental pons?

Answer 340

somatosensory (pain and temperature) from body

Question 341

what type of info is carried by the trigeminothalamic tract in the tegmental pons?

Answer 341

afferent somatosensory from head to cortex

Question 342

what type of info is carried by the lateral lemniscus in the tegmental pons?

Answer 342

auditory relay circuit to inferior colliculus for auditory reflex movement of head

Question 343

what type of info is carried in the rubrospinal tract?

Answer 343

efferent motor signals to the arms

Question 344

what type of info is carried by the tectospinal tract?

Answer 344

efferent somatomotor signals to muscles of neck and shoulders (head turning reflex)

Question 345

what type of info is carried by the spinal nucleus tract of CN 5?

Answer 345

pain and temperature sensation from head

this transitions into the trigeminothalamic tract (in the medulla)

Question 346

what type of info is carried by the descending limbic and hypothalamic fibers of the tegmental pons?

Answer 346

info that is carried to autonomic control centers in medulla and spinal cord

Question 347

list the nuclei that are located in the caudal portion of the tegmental pons

Answer 347

1. facial nucleus CN 7
2. abducens nucleus CN 6
3. spinal trigeminal nucleus CN 5
4. superior olivary nucleus (not pictured below)
5. trapezoid body
6. M/I vestibular nucleus
7. superior salvatory nucleus

Question 348

what does the facial nucleus of CN 7 control?

Answer 348

muscles of facial expression

Question 349

what does the abducens nucles of CN 6 control?

Answer 349

eye muscles (lateral rectus)

Question 350

what do the superior olivary nucleus and trapezoid body do?

Answer 350

they are relays in the auditory pathway

Question 351

what does the superior salvatory nucles do?

Answer 351

fibers are part of CN7 to lacrima, submandibular, and sublingual salivary glands

Question 352

list the nuclei that are located in the rostral pons

Answer 352

1. main sensory nucleus of CN5
2. motor nucleus of CN 5
3. mesencephalic nucleus CN5 (not pictured below)
4. S/L vestibular nucleus
5. locus ceruleus
6. raphe nuclei

Question 353

what is the main sensory nucleus of CN 5?

Answer 353

continuation of spinal trigeminal nucleus (light touch from face via trigeminal ganglion synapses here)

Question 354

what does the motor nucleus of CN 5 supply?

Answer 354

somatomotor

to muscles of mastication

Question 355

what does the mesencephalic nucleus of CN 5 do?

Answer 355

proprioception of jaw (from trigeminal ganglion)

Question 356

what is the locus ceruleus?

Answer 356

part of reticular formation (NE)

involved in pain modulation

Question 357

what is the raphe nucleus?

Answer 357

part of reticular formation (serotonin)

involved in pain modulation

Question 358

what tracts merge together in the rostral pons to form a single tract to the postcentral gyrus?

Answer 358

medial lemniscus

spinothalamic

trigeminothalamic

lateral lemniscus

all merge together into the medial lemniscus

Question 359

what are the 3 general layers of the Midbrain?

Answer 359

1. Tectum = dorsal
2. Tegmentum = intermediate
3. Crus Cerebri = ventral

Question 360

what structures are on the tectum of the Midbrain?

Answer 360

(dorsal layer)

Corpus quadrigemina = S/I colliculi

Question 361

what is the superior colliculi responsible for?

Answer 361

visual reflex response to unexpected stimuli in visual field

Question 362

what is the inferior colliculi responsible for?

Answer 362

auditory reflex respone

Question 363

what is the tegmentum of the midbrain a continuation of?

Answer 363

the pontine tegmentum

Question 364

what are the cerebral peduncles?

Answer 364

crus + tegmentum

Question 365

what is the cerebral aqueduct?

Answer 365

connection between the 3rd and 4th ventricle

Question 366

what are the fiber tracts within the tectum of the midbrain?

Answer 366

posterior commisure

Question 367

what does the posterior commissure do?

Answer 367

coordinate eye movements

Question 368

list the fiber tracts in the tegmentum at the level of the inferior colliculus

Answer 368

1. decussation superior cerebellar peduncle
2. medial longitudinal fasciculus
3. lateral lemniscus
4. medial lemniscus
5. trigeminothalamic
6. spinothalamic

Question 369

what info is carried in the decussation of the superior cerebellar peduncle?

Answer 369

efferent output from cerebellum crosses here

Question 370

what info is carried in the medial longitudinal fasciculus?

Answer 370

balance with efferent limb of balance reflex

Question 371

what info is carried in the lateral lemniscus?

Answer 371

afferent to inferior colliculus for auditory reflex

Question 372

list the tracts located in the tegmentum of the midbrain at the level of the superior colliculus

Answer 372

1. medial longitudinal fasciculus
2. medial lemniscus
3. trigeminothalamic
4. spinothalmic

Question 373

what are the crus cerebri?

Answer 373

descending axons from cerebrum that form corticospinal or corticobulbar tracts

divided into 4 segments

Question 374

tracts in the most lateral segment of the crus cerebri are coming from where?

Answer 374

descending from parietal, temporal, and occipital cortex to pontine nuclei/cerebellum

Question 375

tracts in the most medial segment of the crus cerebri are coming from where?

Answer 375

descending from frontal lobe to pontine nuclei/cerebellum

Question 376

where is the corticospinal tract located in the crus cerebri

Answer 376

lateral middle segment

Question 377

where is the corticobulbar tract located in the crus cerebri?

Answer 377

median middle segment

Question 378

what nuclei are located in the tectum of the midbrain?

Answer 378

1. inferior colliculus (auditory reflex)
2. superior colliculus (visual reflex)
3. pretectal region

Question 379

what supplies the input to the inferior colliculus?

Answer 379

afferent input from:

cochlear, superior olivary, trapezoid nuclei via

lateral lemniscus

Question 380

efferent output from the inferior colliculus heads where?

Answer 380

thalamus

via brachium of inferior colliculus (tectospinal)

Question 381

what supplies the input to the superior colliculus?

Answer 381

retina

Question 382

efferent output from the superior colliculus heads where?

Answer 382

cervical spine

via tectospinal for head turning, and tracking

Question 383

where is the pretectal region located?

Answer 383

rostral to superior colliculus

Question 384

what is the pretectal region responsible for?

Answer 384

papillary light reflex

associated with CN 3

Question 385

what nuclei are located in the tegmentum of the midbrain at the level of the inferior colliculus?

Answer 385

1. substantia nigra
2. periaqueductal gray
3. trochlear nerve nuclei
4. reticular formation

Question 386

what is the substantia nigra?

Answer 386

part of basal ganglia

motor efferent signaling

Question 387

what is the periaqueductal gray responsible for?

Answer 387

autonomic regulation, emotion, and modulation of pain

Question 388

what is the trochlear nerve nuclei CN 4 responsible for?

Answer 388

eye movement superior oblique muscle (down and medial)

Question 389

what is in the reticular formation at the tegmentum of the midbrain at the level of the inferior colliculus?

Answer 389

raphe nuclei

Question 390

list the nuclei that are located in the tegmentum of the midbrain at the level of the superior colliculus

Answer 390

1. oculomotor nerve nuclei CN 3
2. red nucleus
3. ventral tegmental area

Question 391

what is the function for the occulomotor nerve nuclei CN 3 in the tegmentum of the midbrain?

Answer 391

1. somatomotor = S/M/I rectus, inferior oblique, levator palpebrae
2. autonomic motor = iris constriction, ciliary muscle for accommodation (PNS component)

Question 392

what is the red nucleus responsible for?

Answer 392

motor modulation of flexor muscles

via rubrospinal tract

Question 393

what is the ventral tegmental area?

Answer 393

part of the basal ganglia motor modulators

Question 394

what types of sensory information is associated with skin sensation?

Answer 394

1. touch
   
   1. superficial pressure
   2. vibration
2. pain
3. proprioception

Question 395

what type of sensory information is associated with musculskeletal sensation?

Answer 395

1. proprioception
2. pain

Question 396

proprioception can be further broken down to include what?

Answer 396

1. muscle stretch (tension)
2. tendon stretch (tension)
3. deep vibration
4. joint position (angle)
   
   1. during movement
   2. while static

Question 397

what are the different functional receptor types? (based off of stimuli)

Answer 397

1. mechanoreceptors = stretch
2. thermoreceptors = temperature
3. chemoreceptors = any chemical stimuli
4. nociceptors = pain

Question 398

what are the different receptor types based off of response time?

Answer 398

1. tonic = respond the entire time a stimulus is present
2. phasic = adapt to a constant stimulus and stop responding while the stimulus is present

Question 399

what type of receptor is slow adapting? Rapid adapting?

Answer 399

slow = tonic

rapid = phasic

Question 400

what are the different types of sensory neurons?

Answer 400

1. viscerosensory
2. somatosensory
3. special sensory

Question 401

what are viscerosensory neurons?

Answer 401

general visceral afferent (GVA)

carry unconscious signals

Question 402

what are somatosensory neurons?

Answer 402

general sensory afferent (GSA)

carry conscious singals

Question 403

what are special sensory neurons?

Answer 403

special sensory afferent (SSA)

carry sensory info from special senses

Question 404

what structural type of neuron are all viscerosensory and somatosensory neurons?

Answer 404

pseudo-unipolar

made up of:

peripheral (distal) axon/process → soma → central (proximal) axon/process

Question 405

where are the soma of most sensory neurons located?

Answer 405

dorsal root ganglia

OR

cranial nerve sensory ganglia

Question 406

most sensory information will travel in what fiber types?

Answer 406

II or Aβ: medium dia., myelinated

III or Aδ: small dia., myelinated

Question 407

skin sensation is _______sensory

Answer 407

somatosensory

Question 408

what is a receptive field?

Answer 408

an area of skin that is innervated by a single sensory neuron

Question 409

what is the difference between a receptive field and a dermatome?

Answer 409

dermatome = single nerve

receptor field = single neuron

Question 410

the sensation of touch can be broken down into what 2 categories?

Answer 410

Fine and Course touch

Question 411

what type (specific names) of receptors are sensitive to fine touch?

Answer 411

1. Merkel’s
2. Meissner’s
3. Pacinian
4. hair follicle receptor
5. Ruffini

Question 412

what type (specific names) of receptors are sensitive to course touch?

Answer 412

1. free nerve endings

Question 413

pain is sensed by what type of receptor and carried by what type of neuron?

Answer 413

nociceptive receptors (a type of free nerve ending)

Aδ and C neurons carry pain signals

Question 414

temperature is sensed by what type of receptor and carried by what type of neuron?

Answer 414

thermoreceptor

Aδ neurons carry cooling sensation and C neurons carry heat sensation

Question 415

proprioception is primarily sensed by ________

Answer 415

musculoskeletal receptors

BUT

skin receptors make secondary contributions from stretch (Ruffini) and pressure changes

Question 416

proprioception is awareness of joint position and movement that are a result from what receptors?

Answer 416

1. muscle spindles
2. joint receptors
3. cutaneous mechanoreceptors

Question 417

where are muscle spindles?

Answer 417

inside of a muscle, parallel to muscle fibers

structure is referred to as an intrafusal fiber

Question 418

what are the components of a muscle spindle?

Answer 418

1. nuclear chain muscle fiber
2. nuclear bag muscle fiber
3. afferent sensor/receptor
4. gamma motor neuron

Question 419

what are the 2 types of afferent sensor/receptor within a muscle spindle?

Answer 419

1. annulospiral receptor/group Ia sensory neuron
2. flower spray/group II sensory neuron

Question 420

what do annulospiral receptors detect?

Answer 420

dynamic length/stretch (speed of contraction)

associated with both bag and chain intrafusal fibers

Question 421

what do flower spray sensory neurons detect?

Answer 421

static length/stretch (static angle of the joint/degree of stretch)

Question 422

what is the role of the gamma motor neuron within a muscle spindle?

Answer 422

when whole muscle contracts via alpha motor neurons the muscle spindle fibers (intrafusal fibers) may also contract via gamma motor neurons to keep the spindle stretched/tense so it will remain sensitive even when the whole muscle is shortening during contraction

Question 423

what and where are Golgi tendon organs?

Answer 423

a proprioceptive receptor

found in dense CT of tendons

Question 424

what is the role of Golgi tendon organs?

Answer 424

sensitive to changes in tension of the tendon

part of a reflex that inhibits muscle contraction to reduce stretch on muscle/tendon

Question 425

list the different types of joint receptors

Answer 425

1. Paciniform
2. Ruffini
3. free nerve endings
4. ligament receptors

Question 426

what do joint receptor sense?

Answer 426

mechanical deformation of joint capsule and ligaments

(they are mechanoreceptors that are sensitive to stretch)

Question 427

what is the difference between a tract and a pathway?

Answer 427

1. tract = a bundle of axons in CNS with a common origin and destination
2. pathway = peripheral nerve + tract that together carry info to a final destination

Question 428

T/F: pathways are isolated from one another and protected from interference?

Answer 428

FALSE

pathways can communicate and interact via collateral branches and interneurons

Question 429

what are the 3 different classifications of pathways?

Answer 429

1. conscious
2. divergent
3. unconscious

Question 430

what is a conscious pathway?

Answer 430

a pathway that ends in the cerebral cortex

Question 431

what is a divergent pathway?

Answer 431

a pathway that branches and ends in many CNS locations for both conscious and unconscious perception

Question 432

what is an unconscious pathway?

Answer 432

a pathway that ends at brain locations below the cerebral cortex

(brainstem, limbic, cerebellum, diencephalon)

Question 433

Information carried in different pathways can be described as/by ________, _________ and __________

Answer 433

1. fidelity
2. discriminative
3. somatotopic

Question 434

what is fidelity?

Answer 434

describes the location that the signal originates from

high = pinpoint location of origin

low = signals have a general origin

Question 435

discriminative allows ____________

Answer 435

precise identification of stimuli

Question 436

generally conscious pathways have what 3 characteristics?

Answer 436

1. they are 3 projection neuron pathways
2. carry touch, proprioception, pain and temperature info
3. tracts are somatotopically organized (high fidelity)

Question 437

List the conscious pathways

Answer 437

1. Dorsal column/medial lemnsicus tracts
2. Trigeminal nerve
3. Spinothalamic tract

Question 438

what info is carried in the dorsal column/medial lemnsicus tract?

Answer 438

1. discriminative touch
   
   • localization of stimulus
   • 2-point discrimination
2. conscious proprioception
   
   • relative position and movement of body parts

Question 439

what is sterognosis?

Answer 439

identification of an object by touch and proprioception

cortex accomplishes this by processing discriminative touch and proprioceptive info together

Question 440

where/what is the primary/first-order neuron in the dorsal column/medial lemnsicus tract?

Answer 440

pseudo-unipolar neuron

carries signals from periphery to the medulla of the brain stem

Question 441

describe the pathway of the distal axon to the soma of the first-order neuron in the dorsal column/medial lemnsicus tract

Answer 441

1. discriminative touch and proprioceptor receptors
2. peripheral nerve
3. spinal nerve rami (dorsal or ventral)
4. spinal nerve
5. dorsal root
6. DRG (this is the soma)

Question 442

describe the pathway for the proximal axon to the synapse of the second-order neuron in the dorsal column/medial lemnsicus tract

Answer 442

1. DRG
2. dorsal root
3. dorsal column of spinal cord
   
   1. fasciculus cuneatus/gracilis
4. synapses in medulla w/second-order neuron
   
   1. nucleus cuneates/gracilis

Question 443

where/what is the 2 order neuron in the dorsal column/medial lemniscus tract?

Answer 443

soma = nucleus cuneatus/gracilis

axons = cross midline and ascend to VPL of thalamus

Question 444

where does the 3rd order neuron of the dorsal column/medial lemniscus tract originate and terminate?

Answer 444

soma of VPL of thalamus

thru internal capsule

to post central gyrus of parietal lobe

Question 445

what type of sensory info is carried by the Trigeminal nerve?

Answer 445

1. discriminative touch
2. conscious proprioception

from face to contralateral cortex

Question 446

describe the origin, soma and destination of the 1st order neuron in the trigeminal nerve pathway

Answer 446

1. distal axon = receptors located in V1, V2, or V3 branch of the trigeminal nerve
2. soma = trigeminal/semilunar ganglion outside of pons
3. proximal axon = synapses with 1 of 2 nuclei in the pns
   
   • main sensory = sensory info from face
   • mesencephalic = proprioception of jaw

Question 447

describe the origin and destination of the 2nd order neuron in the Trigeminal nerve

Answer 447

1. origin
   
   • soma of main sensory nucleus
   • soma of mesencephalic nucleus
2. axon = cross to contralateral side and ascend in trigeminal lemnsicus (part of medial lemnsicus)
3. terminal synapse = VPM of thalamus

Question 448

describe the origin and destination of the 3rd order neuron in the trigeminal nerve pathway

Answer 448

origin = VPM nucleus of thalamus

destination = post central gyrus via internal capsule

Question 449

what type of sensory info is carried by the spinothalamic tract?

Answer 449

1. discriminative pain
2. temperature
3. course touch
   
   • non discriminative pleasant touch
   • skin to skin contact

Question 450

describe the origin and destination of the 1st order neuron carrying temperature sensation in the spinothalamic tract

Answer 450

1. distal axon = receptors are free nerve endings
2. soma = DRG
3. proximal axon = synapses in dorsal horn
   
   1. Rexed’s laminae I and II = substantia gelatinosa

Question 451

describe the origin and destination of the 2nd order neuron carrying temperature sensation in the spinothalamic tract

Answer 451

1. soma = dorsal horn
2. axon = crosses at spinal cord and ascends in the contralateral anteriolateral column
3. this becomes the spinothalamic tract
4. synapse = VPL nucleus of thalamus

Question 452

describe the origin and destination of a tertiary neuron carrying temperature sensation in the spinothalamic tract

Answer 452

1. origin = VPL nucleus of thalamus
2. destination = post central gyrus

Question 453

how are the neurons carrying localized, fast pain sensation in the spinothalamic tract different from those carrying temperature sensation?

Answer 453

Fast Pain

1. receptors = nociceptors
2. tertiary neurons headed to primary and secondary (associative) somatosensory cortex

Question 454

T/F: fast pain from the face is carried within the trigeminal tract and has the same course as other sensations from the face?

Answer 454

FALSE

it is unique and will first descend to the medulla before ascending to the VPM

Question 455

describe the origin and destination of primary neurons carrying fast pain sensation from the face (trigeminal)

Answer 455

1. distal axon = nociceptive receptors
2. soma = trigeminal/semiulnar ganglion
3. proximal axon = descending tract of trigeminal nerve
4. synapse = spinal nucleus of CN 5 in medulla

Question 456

describe the origin and destination of the 2nd order neuron carrying fast pain sensation from the face

Answer 456

1. origin = spinal nucleus of trigeminal nerve in medulla
2. axon = crosses to contralateral side at the medulla and ascends in trigeminal lemnsicus
3. synapses = VPM nucleus of Thalamus

Question 457

describe the origin and destination of a tertiary neuron carrying fast pain from the face

Answer 457

1. origin = VPM nucleus of thalamus
2. destination = postcentral gyrus and associative cortex

Question 458

Divergent pathways carry both __________ and ___________ signals

Answer 458

conscious

unconscious

Question 459

the medial pain system is a divergent pathway that is generally responsible for carrying info used for what?

Answer 459

1. pain modulation
2. motivational
3. withdrawal
4. arousal
5. autonomic reponse to pain

*low fidelity and not localizable

Question 460

describe the origin and destination of a first order neuron in the medial pain system

Answer 460

1. distal axon = nociceptor receptors
2. soma = DRG
3. proximal axon = branches to multiple spinal cord segments and synapses w/dorsal horn (lamina I, II, and V) using substance P as a NT

Question 461

describe the origin and destination of a 2nd order neuron in the medial pain pystem

Answer 461

1. origin = soma of dorsal horn
2. axon = crosses to contralateral side in spinal cord then ascends in 1 of 3 divergent neurons

Question 462

what are the 3 different divergent neurons that are 2nd order neurons in the medial pain system?

Answer 462

1. spinomesencephalic
2. spinoreticular
3. spinolimbic

Question 463

the spinomesencephalic tract is headed to what structures in the mesencephalon and for what purpose?

Answer 463

1. superior colliculus
   
   • turns head to position eyes on pain source
   • activate descending neurons that modulate pain
2. periaqueductal gray
   
   • descending pain modulation

Question 464

where is the spinoreticular tract headed?

what is it’s role?

Answer 464

reticular formation (raphe nuclei, locus ceruleus)

modulates pain sensation to thalamus

Question 465

what is another name for the spinolimbic tract?

Answer 465

paleospinothalamic tract

Question 466

where is the spinolimbic tract headed and what is it carrying?

Answer 466

1. to anterior cingulated cortex = links pain sensation to emotional response
2. to posterior insula = pain sensation

Question 467

generally, unconscious pathways do what?

Answer 467

carry proprioceptive and feedback info about activity in motor tracts (via interneuron links) to cerebellum to adjust and refine conscious movement

Question 468

what tracts are included in the unconscious pathways?

Answer 468

1. posterior spinocerebellar
2. cuneocerebellar
3. anterior spinocerebellar
4. rostrospinocerebellar

Question 469

which unconsious pathways are high fidelty?

Answer 469

posterior spinocerebellar

cuneocerebellar

Question 470

which unconscious pathways remain ipsilateraly?

Answer 470

posterior spinocerebellar

cuneocerebellar

rostrospinocerebellar

Question 471

what is the posterior spinocerebellar tract?

Answer 471

2 neuron pathway carrying high fidelity, somatotopic info

from lower body to cerebellar cortex

on ipsilateral side

Question 472

describe the origin and destination of a first order neuron in the posterior spinocerebellar tract

Answer 472

1. distal axon = afferent signals from proprioceptors in legs and lower body
2. soma = DRG
3. proximal axon = ascends dorsal column
4. synpases with = dorsal horn >> nucleus dorsalis in T1 to L2 region

Question 473

describe the origin and destination of a 2nd order neuron in the spinocerebellar tract

Answer 473

1. soma = nucleus dorsalis (dorsal horn)
2. axon = ascends ipsilaterally as spinocerebellar tract to the medulla
3. gets to cerbellum via inferior cerebellar peduncle
4. synapses with cerebellar cortex ipsilaterally

Question 474

what is the cuneocerebellar pathway?

Answer 474

2 neuron pathway carrying high fidelity, somatotopic info

from upper body to ipsilateral cerebellar cortex

Question 475

describe the origin and destination of a first order neuron in the cuneocerebellar tract

Answer 475

1. distal axon = afferent signals from proprioceptors in arms and upper body
2. soma = DRG
3. proximal axon = enters spinal cord and ascends in posterior column
4. synapses = lateral (accessory) cuneate nucleus in medulla

Question 476

describe the origin and destination of a second order neuron in the cuneocerebellar tract

Answer 476

1. soma = lateral (accessory) cuneate nucleus of medulla
2. axon = ascends in cunecerebellar tract until it enters the cerebellum via the inferior cerebellar peduncel
3. synapses with ipsilateral cerebellar cortex

Question 477

what is the anterior spinocerebellar tract?

Answer 477

1 neuron pathway that provides cerebellum with feedback from spinal cord ventral horn

monitors motor activity of lower body

Question 478

describe the origin and destination of the neuronal pathway of the anterior spinocerbellar tract

Answer 478

1. soma = interneurons of spinal cord in the thoracolumbar lateral and ventral horns
2. axon crosses to contralateral side
3. ascends in anterior spinocerebellar tract
4. enteres cerebellum via superior cerebellar peduncle
5. collaterals branch to synapse with both cerebellar hemispheres

Question 479

what is the rostrospinalcerebellar tract?

Answer 479

1 neuron pathway that provides the cerebellum with feedback from spinal cord interneurons and motor activity of the upper body

Question 480

describe the origin and destination of the neuronal pathway in the rostrospinocerebellar tract

Answer 480

1. soma = interneurons of cervical spinal cord ventral horns
2. axons asend ipsilaterally in the rostrospinocerebellar tract
3. enter the cerbellum via the S/I cerebellar peduncles
4. synapses w/ipsilateral cerebellar hemisphere

Question 481

where are olfactory receptor cells located?

Answer 481

olfactory epithelium in the roof of the nasal cavity (ethomoid)

Question 482

what is the olfactory epithelium composed of?

Answer 482

1. olfactory sensory/receptor cells (hair cells)
2. supporting cells
3. basal stem cell
4. olfactory glands

Question 483

describe the structure of an olfactory sensory cell

Answer 483

bipolar neurons w/cilia (olfactory hairs) on the end of dendrite

Question 484

T/F: the olfactory sensory/receptor cells are referred to as hair cells but are not neuron

Answer 484

FALSE
these ARE neurons

Question 485

describe the supporting cells in the olfactory epithelium. What are they and what is their function?

Answer 485

mucous membrane lining of nasal cavity, neuroglia cells

function is to support, nourish, insulate, and detoxify olfactory receptor cells

Question 486

what is unique about basal stem cells in the olfactory epithelium?

Answer 486

these are neuronal stem cells

olfactory receptor cells have a lifespan of 1 month and are then replaced

Question 487

what is the function of the olfactory glands?

Answer 487

provide mucous to cover surface of olfactory epithelium to dissolve odor molecules so that they can interact with receptor cells

Question 488

Describe the olfactory pathway up to the point that an AP is generated on CN 1

Answer 488

1. odor molecule dissovles in mucous of nasal surface
2. odor molecule binds to olfactory receptor protein (ligand binding)
3. chemical interaction w/olfactory receptor opens chemical gated channels (Ca and Cl)
4. graded potential on dendrite/soma in olfactory epithelium
5. graded potenials sum at axon hillock to generate and AP on axon of olfactory receptor cell

Question 489

describe the olfactory pathway from when an AP on CN 1 is generated to integration

Answer 489

1. CN 1 axon goes through the cribiform plate to olfactory bulb
2. signlas from olfactory receptor cell activate multiple cells in olfactory bulb for processing signals and discriminating signals
3. olfactory bulb changes the pattern of signaling in response to a new odor
4. olfactory tract carries new pattern to:
   
   1. ipsi and contralateral limbic structures
   2. temporal cortex

Question 490

T/F: the olfactory bulb is always sending signals

Answer 490

TRUE

Question 491

List the various ipsi and contralateral limbic structures

Answer 491

1. Amygdale
2. Entorhinal cortex
3. hippocampus
4. prefrontal cortex
5. Insula

Question 492

where is odor discrimination occuring?

Answer 492

temporal cortex

Question 493

List the accessory structures of the eye

Answer 493

1. eye lid
2. eye brow
3. eye lashes
4. muscles
5. lacrimal apparatus

Question 494

what is the function of the eye lid?

Answer 494

protect the eye

Question 495

what muscles and nerves are responsible for closing the eye lid?

Answer 495

obicularis occuli orbital and palpebral regions

CN VII

Question 496

what muscles and nerves are responsible for opening the upper eyelid?

Answer 496

levator palpebrae superioris

CN 3

Question 497

what is the inner lining of the eyelid called?

Answer 497

palpebral conjuctiva

it is continuous with the sclera

Question 498

what is the function of the lacrimal apparatus?

what controls it?

Answer 498

produce lacrimal fluid (tears)

secreted superior/lateral and will flow diagonally to inferior/medial lacrimal canals which empty into nasal cavity

CN 7

Question 499

List the extrinsic eye muscles

Answer 499

1. Superior rectus
2. inferior rectus
3. lateral rectus
4. medial rectus
5. superior oblique
6. inferior oblique

Question 500

the eyeball can be divided into what 3 layers?

Answer 500

1. fibrous outer layer
2. Vascular middle layer
3. retina-inner layer