Chapter 3
The Neurologic Exam As A Lesson in
Neuroanatomy
Performing the neurologic exam carefully and
presenting findings clearly are crucial to
accurately diagnosing and effectively treating
patients.
Two Goals:
1. Course uses clinical cases so you need to
be familiar with the neurologic exam and how to
interpret normal and abnormal findings.
2. Neurological cases used to learn neuroanatomical
function and clinical localization.
Temperature, pulse, blood pressure, respiratory rate
Neurologic Exam: What is being tested?
1. Mental Status
Level of Alertness, Attention and Cooperation
Simple word task like spelling a word forward and
backward or naming months in sequence forward
and then backward
Level of consciousness impaired in damage to the
brainstem reticular formation, bilateral lesion of thalamus
or cerebral hemisphere.
Also affected in toxic/metabolic injury.
Impaired attention & cooperation are nonspecific and can
occur in many different brain injuries including dementia,
encephalitis, behavioral/mood disorders
Orientation
Full name, location, date
Alert and oriented to person, place & time
A&OX3
If abnormal, record specific questions and answers
Tests recent and longer-term memory
Memory
Recent Memory
Ask patient to recall brief story or 3 items for a delay
of 3-5 mins. Provide distractions during delay.
Remote Memory
Ask patient about historical or verifiable personal
event
If immediate memory is OK, difficulty with recall after
1-5 mins suggests limbic damage
Anterograde amnesia/retrograde amnesia
Language
Spontaneous speech – fluency, phrase length, rate,
abundance, paraphasic errors, neologisms
Comprehension – understand simple questions and
commands
Naming – ask patient to name objects like pen, watch,
tie and some more difficult like belt buckle, stethoscope
Repetition – repeat single words and sentences, “no ifs,
ands or buts.”
Reading – read aloud single words and a brief passage,
test comprehension
Writing – write their name and a sentence
Language abnormalities often caused by damage to dominant
hemisphere, esp. frontal lobe
Calculations, Right-Left Confusion, Finger Agnosia, Agraphia
Impairment of all 4 of these functions in otherwise normal
patient is Gerstmann’s syndrome; aphasia often present
Addition, subtraction, etc.
Identify right and left body parts
Name and identify each digit
Write name and a sentence
“Touch your right ear with your left thumb.”
Indicative of cerebral hemisphere damage, also possibly
thalamus, basal ganglia, cerebellum
Apraxia (inability to follow a motor command not due to
primary motor disorder or language impairment)
“Pretend to comb your hair.”
“Pretend to strike a match and blow it out.”
Awkward movements that only slightly resemble those
requested.
Some affected only in mouth and face or movements of
the whole body such as walking or turning around.
Can be caused by lesions in many different brain regions.
Commonly caused by lesions to language processing areas
and adjacent brain regions of the dominant hemisphere.
Neglect and Constructions
Hemineglect is an abnormality in attention to one side
not due to primary sensory or motor disturbance.
Acute stroke victims are often unaware of any
deficits even if they are paralyzed on the left side and
may be perplexed about why they are in hospital.
Drawing tasks may show this such as bisecting a line or
drawing a clock face.
Construction tasks involve drawing complex figures or
manipulating blocks or other objects
Hemineglect of left side of body most common after
right side brain injuries, esp. parietal lobe; can also
occur after right frontal, thalamic or basal ganglia
injuries
Sequencing Tasks & Frontal Release Signs
Perseveration – difficulty changing from one action to
the next.
Luria manual sequencing task often used. Patient asked
to tap table with fist, open palm and then side of hand
and repeat sequence as quickly as possible.
Auditory go-no go test where one finger is raised in
response to one tap on the table, but must be kept still
in response to 2 taps.
Frontal lobe damage often produces changes in
personality and judgement or very slow responses
Logic and Abstraction
Can patient solve simple problems: “If Mary is taller
than Jane, and Jane is taller than Ann, who’s the
tallest?” What is meant by “Don’t cry over spilled
milk?” “How are a car and an airplane alike?”
Functions can be disrupted by injury to a variety of
brain areas, esp. association cortex.
Delusions and Hallucinations
“Do you ever hear or see things that other people do
not hear or see?”
“Do you feel that someone is watching you?”
“Do you have special abilities or powers?”
Focal lesions or seizures in visual, somatosensory, or
auditory cortex.
Thought disorders can be caused by damage to the
limbic system or association cortex.
Mood
Depression, anxiety, mania
Changes in eating & sleeping patterns, loss of energy
and initiative, low self-esteem, poor concentration,
self-destructive or suicidal thoughts/behaviors.
Psychiatric disorders may involve imbalance in
neurotransmitters.
Sometimes also seen in toxic/metabolic disorders such
as thyroid dysfunction.
Neurologic disorders such as brain tumors, strokes,
metabolic derangements, encephalitis, vasculitis, etc.
may produce confusional states or bizarre behavior
that may be interpreted as a psychiatric disorder.
2. Cranial Nerves
Careful testing of the cranial nerves can reveal crucial information
to help pinpoint neurologic disorders.
Olfaction (CN 1)
Test odor of coffee or soap in each nostril.
Impairment can be due to nasal obstruction, damage to olfactory
nerves, intracranial lesions affecting olfactory bulb.
Vision (CN 2)
Visual acuity – each eye, use eye chart.
Color vision – each eye, color chart; red desaturation each eye
Visual fields – fixate and report when a finger can be seen moving
into each quadrant; how many fingers are shown in each quadrant
In comatose patients visual fields can be tested using blink-to-threat.
Visual extinction – double simultaneous stimulation, seeing multiple
fingers presented on both sides simultaneously; not seeing them
on one side may indicate hemineglect
Testing damage to visual pathway from retina to visual cortex.
Pupillary Responses (CN 2, 3)
Pupil size and shape at rest
Direct response to light; consensual response
Ipsilateral optic nerve, pretectal area, ipsi. Parasym.,
pupillary constrictor muscle
Afferent pupillary defect: swinging flashlight test;
affected eye shows pupil dilation when light swings to
it
Contralateral optic nerve, pretectal area, ipsilat.
parasym., pupillary constrictor muscle
Accommodation: pupils constrict while fixating on
object moving toward the eyes.
Ipsilat optic nerve, ipsilat parasym, pupillary constrictor
muscle, bilat lesions of optic tracts; spared in lesions
of pretectal area that may impair pupillary light
response
Extraocular Movements (CN 3, 4, 6)
Check eye movements in all directions.
Check smooth pursuit in horizontal and vertical directions.
Test convergence by moving object slowly toward nose.
At rest see if spontaneous nystagmus or dysconjugate
gaze present.
Test optokinetic nystagmus with striped paper strip.
In comatose patients use oculocephalic or caloric tests.
Tests evaluate cranial nerves 3, 4, 6; cranial nerve
nuclei; higher order centers in cortex and brainstem
that control eye movements
Spontaneous nystagmus can indicate toxic/metabolic
disorder, drug overdose, alcohol intoxication, or
peripheral/central vestibular dysfunction
Facial Sensation and Muscles of Mastication
Test facial sensation with cotton wisp and sharp pin.
Test corneal (blink) reflex (CN 5, 7) using cotton wisp.
Feel masseter muscles during jaw clench; test jaw jerk reflex.
This tests trigeminal nerve and nuclei, ascending paths to
thalamus and cortex
Corneal reflex mediated by CN 5 & 7
Weakness in jaw muscles can be due to lesions in UMN to
trigeminal motor nucleus, trigeminal motor nucleus,
trigeminal nerve or muscles.
Presence of jaw jerk reflex is abnormal and may indicate
hyperreflexia a sign of UMN injury.
Muscles of Facial Expression and Taste (CN 7)
Look for asymmetry in facial expressions and depth
of nasolabial folds.
Facial weakness may be difficult to detect in cases
where it is bilateral.
Ask patient to smile, puff out cheeks, clench eyes
tight, wrinkle their brow.
Check taste with sugar, salt or lemon juice on cotton
swabs applied to each side of tongue.
Facial weakness due to UMN or LMN lesion in path
controlling facial muscles. Unilateral UMN lesion
causes weakness/paralysis in lower face only due to
bilateral innervation. LMN lesion causes upper and
lower face weakness/paralysis
Taste tests facial nerve and nucleus solitarius.
Hearing and Vestibular Sensation (CN 8)
Simple hearing test, rub fingers near each ear or
whisper softly near each ear.
Tuning fork used to differentiate neural from mechanical
hearing loss.
Vestibular sensation is not generally tested except in
the following situations:
Patients with vertigo
Patients with limited horizontal/vertical gaze
Patients in coma
Tests integrity of receptors, CN 8, nuclei & pathways.
Palate Elevation and Gag Reflex (CN 9, 10)
Does palate elevate symmetrically when say “Aah?”
Normal gag reflex?
Tests integrity of CN 9 & 10, nuclei and muscles of
pharynx.
Muscles of Articulation (CN 5, 7, 9, 10, 11)
Speech hoarse, slurred, quiet, breathy, nasal, low or high
pitched?
Tests integrity of CN 5, 7, 9, 10, 11, nuclei and muscles.
Speech production can also be affected in lesions of
cerebellum, motor cortex, basal ganglia or paths to
the brainstem
Sternocleidomastoid and Trapezius Muscles (CN 11)
Shrug shoulders, turn head in both directions and
raise head from bed against force of your hand.
Test for weakness in these muscles is indicator of
lesion in CN 11, nucleus or muscles
Tongue Muscles (CN 12)
Note any atrophy or fasciculations in tongue muscles.
Stick tongue straight out, note any deviation.
Move tongue side to side and push against cheek.
Unilateral lesion causes deviation toward weak side.
Test for weakness is indicator of lesion in CN 12,
nucleus, motor cortex, or connections.
3. Motor Exam
Observation, inspection, palpation, muscle tone testing,
functional testing, strength testing.
Observation
Look for twitches, tremors, involuntary movements,
unusual paucity of movement.
Involuntary movements often due to lesions in basal
ganglia or cerebellum; tremor due to nerve lesion.
Inspection
Look for muscle wasting, hypertrophy,
fasciculations, esp. hands, shoulder, thigh.
Palpation
Look for tenderness, symptom of myositis.
Muscle Tone Testing
Passively move limbs at joints to detect rigidity
or resistance
Hyperreflexia indicates UMN lesion.
Hyporeflexia indicates LMN lesion.
Acute UMN lesions often show flaccid paralysis;
after hrs/days hypertonia/hyperreflexia.
Slow/awkward foot tapping/finger movements can
indicate corticospinal, cerebellar, basal ganglia
lesions.
Strength of Individual Muscle Groups
Patterns of weakness can help localize lesion.
Test strength of each muscle group and record.
Pair testing of contralateral muscle groups to see
asymmetry.
Scale 0/5 to 5/5 used.
0/5 = no contraction
1/5 = muscle flicker but no movement
2/5 = movement possible; not against gravity
3/5 = movement possible against gravity but
not against resistance
4/5 = movement possible against some resistance
5/5 = normal strength
Tests muscle, LMN, peripheral nerves and roots
4. Reflexes
Deep tendon reflexes and plantar response should
be checked in all patients; other reflexes should be
tested in special situations.
Deep Tendon Reflexes
Use reflex hammer and check contralateral side right
after ipsilateral to compare magnitude.
Clonus is a repetitive vibratory contraction and indicates
hyperreflexia.
0 = absent reflex
1+ = trace or seen only with reinforcement
2+ = normal
3+ = brisk
4+ = nonsustained clonus
5+ = sustained clonus
Reflexes can be abnormal in disorders of muscle, nerves, roots, and
UMN/LMN injury
Plantar Response
Scrape object on sole of foot.
Babinski sign indicative of UMN lesion.
Normal in infants up to 1 yr.
5. Coordination and Gait
Cerebellar damage often affects these functions.
Abnormalities include ataxia (appendicular & truncal),
overshoot, past pointing, dysdiadochokinesia
Appendicular coordination – rapid alternating
movements, finger-nose-finger test, heel-shin
test.
Romberg test – tests integrity of cerebellum, vision,
proprioception and vestibular sensation.
Gait – stance, posture, stability; gait apraxia is puzzling
abnormality in which patient can carry out all
movements of walking while prone, but not
while upright.
6. Sensory Exam
Primary sensation, asymmetry, sensory level
Pain, temperature, vibration, joint position
two-point discrimination
Cortical sensation (higher level processing)
Graphesthesia, stereognosis
Intact primary sensation with deficits in cortical
sensation suggests lesion in contralateral
sensory cortex.
Coma Exam
1. Mental Status
Coma = unarousable unresponsiveness in which
patient lies with eyes closed.
5. Reflexes
Flexor and extensor posturing
Flexor posturing
Higher lesion, midbrain
or above
Extensor posturing
More severe lesion including
lower down in brainstem
Triple flexion
Response to pinch on foot
Spinal cord circuitry; not
normal withdrawal
Brain Death = irreversible lack of brain function; exact
criteria may vary with hospital. No evidence of brain
function, including brainstem. Caloric testing and apnea
test (lack of spontaneous respirations when off respirator).
In U.S., patient with posturing reflexes involving brainstem
does not meet brain death criteria, but one with only triple
flexion and deep tendon reflexes may.
Must test for reversible causes of coma including hypoxia,
hypoglycemia, hypothermia, drug overdose, etc.
Conversion Disorder, Malingering, and Related Disorders
Conversion disorder = psychiatric illness causes patient to
have sensory or motor deficits without focal lesion.
Patient is not consciously faking and they often believe
that they have a nonpsychiatric condition.
Factitious disorder (formerly Munchausen syndrome) where
patient feigns illness bcz they gain some emotional
pleasure from assuming role as patient.
In malingering, the ulterior motive involves some external
gain for the patient such as avoiding work, obtaining
disability benefits, or avoiding unpleasant home situation.