What makes up the CNS?
brain and spinal cord
What makes up PNS?
cranial nerves and spinal nerves
How many pairs of cranial nerves are there? Spinal nerves?
Name the meningeal layers and spaces from superficial to deep.
- epidural space
- subdural space
- subarachnoid space
- pia mater
*pia = faithful (like pious). This layer faithfully follows all the contours of the brain b/c it's the closest to it.
Where do the high functions of the brain take place?
examples of high functions?
high fx: thought, memory, reasoning, sensation, voluntary mvmts
name the 4 lobes of each brain hemisphere
which lobe is responsible for personality, behaviors, emotions, and intellect
where is the motor cortex? what does it do?
frontal lobe, precentral gyrus.
responsible for voluntary skeletal muscle mvmt and fine repetitive mvmt
where is broca's area? which type of aphasia results if it is damaged?
frontal lobe of dominant hemi. results in expressive aphasia - can't articulate words (talk), but can write
where is the sensory cortex?
parietal lobe, postcentral gyrus
which lobe is responsible for vision?
what does the temporal lobe control?
- interpretation of sound
- integration of taste and smell
where is wernicke's area? which type of aphasia results if damaged?
receptive aphasia - can understand sounds, but can read
increased muscle tone (rigidity), ataxia, and bradykinesia result form damage to what part of the NS?
basal ganglia (the gray matter lying deep in brain)
what disease effects basal ganglia?
the thalamus and hypothalamus make up which brain structure?
what does the hypothalamus regulate?
- anterior and posterior pituitary
- coordination of ANS activity
- emotional status
name the 3 components of the brain stem
what is pyramidal decussation? where does it occur?
crossing of motor fibers from one side of the body to other.
occurs in medulla
from where do most cranial nerves originate?
from where does CN1 originate?
from where does CN2 originate?
which cranial nerves originate in the midbrain?
which cranial nerves originate in the pons?
which cranial nerves originate in the medulla?
where is the autonomic center? what does it control?
medulla. controls respiration, heart, GI fx
which part of the brain coordinates mvmts and maintains equilibrium, posture, and muscle tone?
damage to which part of the brain would result in problems with gait and decreased muscle tone?
cerebral artery blockage will cause permanent brain damage if not treated with thrombolytics within how much time?
trace sensation from stimulus to brain
afferent fibers in peripheral nerves --> enters spinal cord thru dorsal/posterior root --> up spinal cord to brain stem --> pyramidal decussation and travels to thalamus --> sensory cortex
spinothalamic track conducts sensation of:
- crude/light touch
- deep pressure
posterior columns conduct sensation of what?
- deep pressure
- fine touch
give 3 examples of fine touch
- 2-point discrimination
which motor tract relays voluntary mvmt?
corticospinal / pyramidal
trace motor impulse from brain to LMN
motor cortex --> brain stem --> pyramidal decussation (cross to other side of brain stem) --> down spinal cord until synapses with LMN contained in the spinal cord
which motor tract is controlled by basal ganglia?
trace path of motor impulse from brain to spinal cord
motor cortex --> basal ganglia --> brain stem --> spinal cord
which part of the NS controls DTRs?
name anatomical landmarks for beginning and end of spinal cord
- begins at foramen magnum of skull
- ends at L1-2 of vertebral column
name the 2 functional parts of the cranial and spinal nerves
- somatic fibers - innervated skeletal/voluntary mm
- autonomic fibers - innervate involuntary mm and glands
name the 12 cranial nerves
handy pneumonic, courtesy of Chelsea: Oh, Oh, Oh, to take a family vacation, go Vegas after hours.
- Accessory (spinal accessory)
Name how many of each spinal nerve pairs exit at each vertebral level. Ex: cervical, thoracic, etc.
- Cervical - 8
- Thoracic - 12
- Lumbar - 5
- Sacral - 5
- Coccygeal -1
motor fibers exit the spinal cord thru where? sensory fibers enter thru where?
- motor exit: ventral
- senSORy enter: dORSal
what's a dermatome?
a circumscribed area supplied by mainly one spinal cord segment
give 2 exmaples of LMN diseases
- myesthenia gravis
give 2 examples from notes of UMN disease
CVA, multiple sclerosis
paresis vs. paralysis
- paresis is slight paralysis/weakness
- paralysis is complete loss of motor fx
both are motor sx
PMH pertinent to neuro exam
- SCI (spinal cord injury)
- congenital defect
what score is used to measure birth trauma in children?
define micturition syncope
when male faints while urinating d/t decreased cerebral blood flow
what is the exam sequence for the objective portion of a neuro exam?
- mental status
- cranial nerves
- motor/cerebellar fx
- sensory system
define anosmia. which CN is involved?
loss of sense of smell. involves CN1 - olfactory
name 3 tests used to test CN2
- Snellen - tests visual acuity
- confrontation - tests visual fields
- fundoscopic exam
which 2 CNs are involved in PERRLA? which is afferent? efferent?
- CN2: optic - afferent
- CN3: oculomotor - efferent
which CN is responsible for ptosis? what would you observe in a pt with ptosis?
- CN3: oculomotor
- ptosis = unequal palpebral fissures
what eye mvmts do CN3, 4, and 6 control? how do you assess them?
- 3 (oculomotor): most eye mvmts
- 4 (trochlear): down and inward eye mvmts, controls superior oblique muscle
- 6 (abducens): lateral eye mvmt
assess with EOMs, look for nystagmus
which CN is responsible for sweet and salt taste on the anterior 2/3 of the tongue?
facial / 7
which CN is responsible for innervating the muscles involved in chewing? which muscles are they?
CN 5 / trigeminal
mm: temporal, masseter
where are the 3 zones of sensation that the trigeminal nerve is responsible for? how do we test them?
test with light touch (cotton wisp) to forehead, cheeks, and chin
which CN is responsible for facial mvmts and expression
facial / 7
which CNs are responsible for the blink reflex? what is another name for this reflex?
blink reflex aka corneal reflex
how do we test CN8
- whisper test
which CN is responsible for sour and bitter taste on the posterior 1/3 of tongue?
CN9 / glossopharyngeal
which CN is responsible for shoulder strength?
CN 11 / spinal accessory
how do we assess CN 9 and 10 fx?
- say "ahhh," look for soft palate rise
- gag reflex
which CNs are responsible for talking and swallowing?
CN9 and 10 / glossopharyngeal and vagus
how do we assess CN12?
assess tongue posn, looking for deviation towards paralyzed side
test tongue strength against cheek resistance
what does Romberg's test assess? how do you do it?
assesses balance, CN8 fx
stand with feet together, eyes closed for 20sec. positive test if pt takes a step.
name 4 tests to assess upper extremity coordination
- thumb to each finger
- finger-to-finger (pt's to examiner's)
- finger-to-nose with eyes closed
how do you assess muscle tone?
check resistant to passive muscle stretching (e.g., flex and extend arm)
name 2 ways to assess lower extremity coordination
- tap feet on floor repeatedly
- heel-to-shin test
what's the best way to test for peripheral neuropathy? for which population is this especially important?
use monofilament (10gm)
muy importante for diabetics
when assessing pain sensation of the spinothalamic tract, why wait 2 sec b/w each check?
<2 sec will lead to summation of stimuli that will be perceived as one
no pain perception
how do you assess the deep pressure sensation of the spinothalamic tract?
squeeze trap, calf, or biceps
which type of sensation is usually lost first with peripheral neuropathy? how do we test for it?
test with tuning fork at DIP of fingers and big toes
what is kinesthesia? how do you assess for it?
move finger or toe up or down and ask pt to ID position
what is astereognosis?
the inability to recognize objects by feel
what is graphesthesia?
the ability to read a letter or number traced on the skin
where on the body is 2-point discrimination most sensitive?
simultaneously touching both sides of the body in the same location tests for what?
sensory extinction. if only felt unilaterally, extinction has occurred.
name the 5 examples of fine touch sensation
- 2-point discrimination
- point location
trace the DTR pathway
begins at sensory / afferent nerve --> synapses at spinal cord --> motor / efferent nerve --> neuromuscular junction (consists of nerve dendrite and muscle spindles --> ends with functioning muscle response
what does the neuromuscular junction consist of?
nerve dendrites and muscle spindles
what do DTRs reveal about the spinal cord?
its intactness at specific levels
describe reflex grading scale
- 4+ hyperactive
- 3+ above avg
- 2+ normal
- 1+ low normal
- 0 absent
with CVAs, you expect to see what kind of reflexes (hyper/hypo/normal)? why?
hyperreflexia - seen with UMN lesions.
normally reflexes or modulated by high cortical inhibition in the brain, but when brain is damaged, this inhibition is lost and reflex is hyperactive
with SCIs, you expect to see what kind of reflexes (hyper/hypo/normal)?
incomplete quadriplegia is seen with spinal cord injuries below what level?
incomplete below C6, complete above C6
which spinal nerves are involved in the brachioradialis DTR?
which spinal nerves are involved in the biceps DTR?
which spinal nerves are involved in the triceps DTR?
which spinal nerves are involved in the quadriceps / patellar DTR?
which spinal nerves are involved in the achilles DTR?
S1-2 (according to notes, book includes L5)
name the 4 superficial reflexes listed in the notes
- upper abd
- lower abd
- plantar reflex / babinski
which spinal nerves are involved in the upper abd reflex?
which spinal nerves are involved in the lower abd reflex?
which spinal nerves are involved in the cremasteric reflex?
how do you assess the cremasteric reflex?
stroke inner thigh of male, testicle and scrotum should rise
which spinal nerves are involved in the plantar reflex? what's another name for this reflex?
for what population is a positive babinski abnormal? what would you see with a positive test?
abnormal in adults. normal in kids <2 y/o.
dorsiflexion of big toe and fanning of other toes when stroking lateral aspect of sole of foot
which 3 factors does the glasgow coma scale use to assess LOC?
- eye opening
- verbal response
- motor response
what's the name for a herniation of the brainstem? what would happen if this caused pressue on CN3
pressure on CN3 - would see unilateral, dilated, and nonreactive pupil
VS changes are an early or late sign of ^ ICP? what changes would you see?
- increased SBP with widening pulse pressure (pulse pressure = SBP - DBP)
- decreased HR
what is nuchal rigidity? what is it a sign of?
extremely stiff neck.
sign of meningeal irritation
what is prolonged arching of the back with head and knees bent backward called?
what is decorticate position? damage to which part of the NS would cause this?
flexor posturing, with arms brought to core of the body, look like a mummy
damage to cerebral cortex
CORtex --> arms to CORE of body
what is decerebrate position? damage to what part of the NS would cause it?
extensor posturing, with extended arms and LEs
damage to brain stem
what is dyskinesia? for what population is it common?
repetitive mvmt in jaw, lips, or tongue.
seen in older adults