neuro exam 2: week 4

major function of the spinal cord (1)

chief input and output site for sensory and motor signals below the neck

major function of the spinal cord (2)

transmission of ascending and descending information via fiber tracts

cervical region contains the vertebrae

CI-CVII

thoracic region contains vertebrae

TI-TXII

lumbar region contains vertebrae

LI-LV

sacral region contains vertebrae

sacrum and coccyx

are the spinal nerves represented with roman numerals or numbers?

numbers (ex: C1)

spinal nerves include

dorsal root AND ventral root

what do the dorsal root and ventral root do?

convey both sensory and motor information

general somatic efferent (GSE)

efferent (motor) and somatic (skeletal muscle)

general visceral efferent (GVE)

efferent (motor) and visceral (smooth/cardiac muscle, glands)

general somatic afferent (GSA)

afferent (sensory) and somatic (skeletal muscle)

general visceral afferent (GVA)

afferent (sensory) and visceral (smooth/cardiac muscle, glands)

complete spinal cord injury

loss of motor and sensory function

incomplete spinal cord injury

retained motor and/or sensory function

paraplegia

loss of movement of the lower body and limbs

regions affected by paraplegia

thoracic, lumbar, sacral

tetraplegia

loss of movement of the upper and lower body and limbs

regions affected by tetraplegia

cervical

respiratory muscle(s) associated with C3-C5

diaphragm

respiratory muscle(s) associated with T1-T11

external intercostals

internal intercostals

respiratory muscle(s) associated with T7-T12

rectus abdominis

transverse abdominal

external oblique

internal oblique

neurological level of injury (NLI)

rostral most (superior) intact nerve

retained sensory and motor function bilaterally

ASIA A classification

complete

ASIA B classification

sensory incomplete (motor complete)

ASIA C classification

motor incomplete (< half spared)

ASIA D classification

motor incomplete (half or more spared)

medulla functions (1)

passage for motor and sensory axons

medulla functions (2)

cranial nerve functions (hearing, balance, swallowing, voice, head and tongue movement)

medulla functions (3)

reticular formation

reticular formation

cardiovascular (regulating blood pressure and heart rate) and respiratory function

pons function: basilar pons (ventral part)

passage for sensory and motor axons

grey matter (pontine nuclei)

pons function: tegmentum (dorsal part)

cranial nerve functions (facial movements)

reticular formation

PAG (voice and aspiration)

midbrain function: cerebral peduncle (ventral part)

axon passage

grey matter (substantia nigra)

midbrain function: tegmentum (middle part)

cranial nerve functions (eyes)

reticular formation

PAG (voice, emotion, autonomics, pain)

midbrain function: tectum (dorsal part)

superior col (reflective vision)

inferior col (sound localization

respiratory centers

pons respiratory centers

medullary respiratory center

what is auditory brainstem response (ABR)

newborn hearing screening

how is ABR preformed

electrodes detect minor electrical changes in the skin from brainstem and CN VII activity

where are the cell bodies of efferent lower motor neurons located

ventral horns of the spinal cord

spinal nerves contain

both afferent and efferent fibers

which of the following levels of spinal cord injury would be most likely to warrant use of assisted coughing

C3 ASIA C

true or false: normal ABR involve the primary auditory cortex of the cerebrum

false

what is a function of all three components of the brainstem

axon pasage

where does the spinal cord stop matching ratio

mid-low thoracic

where do spinal nerves exit (except cervical)

below their corresponding vertebrae

fibers that form the cauda equina are

both sensory and motor

what is the dorsal root ganglia made of

grey matter

transverse foramen

where the vertebral artery comes through

vertebral artery

supplies blood to the spinal cord and brain

superior costal and transverso-costal facet

connect the thoracic section of the spinal cord to the ribs (think intercostals)

why are there more “shoot offs” in the lumbar/thoracic section of the spinal column

because they connect to more

why is there more grey matter in the cervical/lumbar level of the spinal cord

there’s a greater amount of motor nerves/action

lateral fasciculus sensory function

noxious stimuli (bad taste/smell)

crude touch

body position

lateral fasciculus motor function

fine motor movements

anterior fasciculus sensory function

noxious stimuli (bad taste/smell)

temperature

anterior fasciculus motor function

trunk control

posture

lower motor neurons (LMN)

feed the motor portion of spinal cord grey matter

roots

cell bodies that extend outside the spinal cord

pia matter function

gives structure

subarachnoid space

weblike (think spider)

pseudounipolar cells

more common for sensory neurons

CNS grey matter components

cortex (gyri and sulci)

nucleus

PNS grey matter components

ganglion

CNS white matter components

fasciculus

fiber bundle

tract

pathway

etc

PNS white matter components

nerves

which type of spinal cord fiber is more likely to be in the dorsal root columns

general somatic afferent (GSA) because it is more specific

what do general visceral efferent (GVE) spinal cord fibers control

internal organs

when are SLPs most likely to work with a SCI patient

when the cervical or thoracic SC is primarily injured

diaphragmatic breathing (belly breathing)

used to improve respiratory support for speech

assisted cough

applying compensatory pressure to the abdomen to help clear secretions

when should you generally not used assisted cough

when the patient has a feeding tube

brainstem function (1)

controls the automatic regulation of things like heartbeat, blood pressure, breathing, etc

brainstem function (2)

site for the nuclei of the cranial nerves

basis pontis

middle of the pons

what does the tegmentum cover

the full length of the brainstem

pyramidal descussation

where the pyramids cross over

MPM sandwich

medulla

pons

midbrain

cauda equina function

transmits sensory and motor signals between the central nervous system and the lower limbs

which nerves are intact in a spinal cord injury at the level of C3

C3 and above

how do grey matter and white matter differ throughout the spinal column? why?

At different parts of the spinal column, the proportion of gray matter to white
matter changes such that the lumbar region has the highest proportion of gray
matter, and the thoracic level has the lowest proportion of gray matter. The parts of the spine with more gray matter have more cell bodies to innervate more muscles/larger parts of the body. These areas also correspond to higher
sensitivity/more sensory info being sent to CNS.

what region of the spinal cord is this

thoracic

what region of the spinal cord is this

cervical

which region of the spinal cord is this

lumbar

a T5 ASIA injury might affect which regions

external intercostals

transverse abdominal

internal oblique

what type of information is primarily carried by the posterior fasciculus (dorsal columns)

somatic sensory

what can the coccygeal nerve be referred to as

CO1, S6

the two major functions of the spinal cord are: chief ___ and ___ site for ___ and ___ signals below the ___ as well as the transmission of ___ and ___ information via ___

input

output

sensory

motor

neck

ascending

descending

fiber tracts

order or the brainstem from superior to inferior

midbrain

pons

medulla

what type of spinal cord fiber would be affected if the dorsal horn of the spinal cord white matter was compromised

general somatic afferent

describe the pathway of information from the brain to skeletal muscle for movement via motor neurons

the primary motor cortex efferently sends information through the spinal cord via upper motor neurons through the dorsal horn, lower motor neurons exit the spinal cord through the ventral horn towards the skeletal muscle to innervate a motor movement

medulla function

primarily involved in regulating blood pressure, heart rate, and respiratory function

provides a passage for motor and sensory axons, and contributes to cranial nerve functions involved in hearing, balance, swallowing, voice, and head and tongue movement

pons function

provides a passage for sensory and motor axons, contributes to respiration in the reticular formation, contributes to cranial nerve functions involved in facial movements, and vocalization in the periaqueductal gray (PAG

midbrain function

involved in eye movements via the cranial nerve, voice, emotional processes, autonomic activity, and the perception of pain in the PAG, and provides an axon passage

tectum in the midbrain contains the inferior colliculus involved in sound localization and the superior colliculus involved in reflexive vision

label the layers of the meninges correctly

dura matter

periosteal

meningeal

arachnoid layer

pia matter

true or false: spinal nerves include dorsal root fibers that convey sensory and motor function

true

describe the primary purpose of the posterior fasciculus in the white matter of the spinal cord (includes type of information that is conveyed and where this information comes from)

the posterior fasciculus in the white matter of the spinal cord conveys the
somatic sensory information that ascends to the CNS

afferent fibers that carry sensory information that comes from the joints, skin, and skeletal muscle

describe the difference between paraplegia and tetraplegia

paraplegia is the loss of movement in the lower body and limbs due to a thoracic, lumbar, or sacral injury

tetraplegia is the loss of movement in the upper body AND lower body and limbs due to a cervical injury

another name for the cerebral penduncles

crus cerebri