Chapter 7: Neurological examination

What is a Neurological Examination?

A series of tests conducted by a neurologist to evaluate the integrity of the nervous system for many reasons, including (but not limited to)

• Following trauma or stroke

• When there are suspected neurodegenerative changes (ex. Cumulative change in brain from playing sports)

• Following exposure to a neurotoxic agent

Localization

Cerebral Hemisphere (Telencephalon)

Internal Capsule

Brainstem (Diencephalon, Mesencephalon, Metencephalon, or Myelencephalon?)

Spinal Cord

Cranial Nerves

Neuromuscular Junction

Muscle

Overview of common components of exam

1. Patient history

2. Cranial nerve function

3. Motor function (e.g., reflexes)

4. Somatosensory function

5. Coordination

6. Mental status

Patient history: Age, education and handedness

Just going to Post-secondary school → less likely to have cognitive impairment later in life, like dementia

Right-handers and left-hemisphere dominance

Patient history (cont’d)

Past medical history

Use of prescription and/or recreational drugs

Family medical history

Disease Process:

• Temporal profile: sudden vs. gradual; acute vs. chronic

• Change over time: static, improvement, worsening

• Identify triggers/relievers of symptoms

• Gauge severity of symptoms

Memorize cranial nerves

Oh Oh Oh, To Touch And Feel Very Good Velvet, Ah Heaven

Some say money matters, but my brother says big brains matter more

Olfactory (I)

Damages that cause (I) dysfunction: Ethmoid ridge (bones behind nose), cribriform plate (also another bones with axons, injured → cut axons, and TBI

Damage: Can’t smell

Optic (II)

Standard visual acuity tests for each eye

Visual field confrontation

Papilledema (swelling of optic disk) due to intracranial pressure

Nystagmus

Damages cranial nerves III, IV, VI.

A condition characterized by involuntary, repetitive eye movements, which can cause reduced vision and depth perception

Oculomotor (III)

Eyelid motor

Damage: Ptosis

Ptosis

Damages III

Droopy eyelids, block the view to see

Trochlear (IV)

Moves the eye down and in

Trigeminal (V)

Facial somatosensation (put cotton, “can you feel”?)

Motor function (feel muscle by clenching teeth)

Reflex (put cotton close to eye, see if they blink)

So test the forehead, cheekbones, chin

Abducens (VI)

Moves eye outward (abduction)

Facial (VII)

Facial expression: Smile, frown, wrinkle their forehead

Taste: Anterior tongue

But we don’t really test taste! We are bad at it. Sick/too hot food → temporarily lose taste

Damage: Bell’s Palsy (temporary facial asymmetries)

Bell’s Palsy

Half droopy face, facial paralysis, impaired taste

Vestibulocochlear (VIII)

Auditory perception (Close one ear, whisper to another ear, “can you hear”?)

Balance

Glossopharyngeal (IX)

Taste and sensation from posterior tongue

Gag reflex, Swallowing, Coughing, Voice

Hard to detect

Vagus (X)

Parasympathetic NS: Motor control of heart, lungs, digestive system, etc.

Outer ear canal sensation

Gag reflex, Swallowing, Coughing, Voice

Hard to detect

Accessory (XI)

Shrugging of shoulders

Head resistance

Hypoglossal (XII)

Movement of tongue (push tongue against your cheek), NOT TASTE, lateral movement of tongue, speech, swallowing

Motor neurons

This motor neuron travels down the spinal cord to muscles

Upper motor neuron (not the last stop) sends signal from motor cortex and brainstem, down to the spinal cord, lower motor neuron receives it, and sends it out to muscles, and causes them to contract

They causes reflex! Like the knee-jerk. This type of assessment test the stretch reflex.

Upper motor neuron lesions

Descending Inhibition

Exaggerated reflex (hyperreflexia)

Muscle spasm

Lower motor neuron lesions

Reduce reflex (hyporeflexia)

Lower muscle tone

Descending inhibition

The suppression of reflex activity and muscle tone by signals from the brain and upper motor neurons to the spinal cord. This process helps prevent excessive reflexes.

This is why upper motor neuron lesions → leads to removal of descending inhibition → leads to removal of this reflex suppression → leads to excessive reflex (hyperreflexia)

Key features to examine in motor function

Gross appearance of muscle

Muscle tone, strength

Somatosensory function

Pain

Light touch and proprioception

Testing for Astereognosis

Testing for Graphesthesia

Proprioception

The ability to know where your body parts are in space.

Can be tested by blindfolding you and put your right arm behind your back. If you have this impairment, you will not know where your right arm is when you’re blindfolded

Damage caused by: Cortical strokes

Astereognosis

Inability to perceive the object by touch (ex. hold an eraser, and can’t guess what’s in their hand)

Graphesthesia

Inability to recognize symbols/numbers/letters traced on skin (like back or hand)

Coordination

Quick, alternating movement

Point-to-point movement: Move your finger towards your nose. Cerebellum damage if you can’t do it

Heel-to-shin: Lie on the side, and swing your foot in the air from heel to shin rapidly. Cerebellum damage if you can’t do it

Resistant to sitting/standing

Gait: Walking normally to check smoothness, balance, and symmetry

Coordination: Romberg test

Test cerebellum, vision, vestibular function

But, this test will take out ⅓, which is vision, leaving behind only cerebellum sense, and vestibular sense. So if you have both intact, you’ll do fine, but if you’re missing one (cerebellum OR vestibular) it’ll be very obvious.

The patient stands with feet together, and arms at their sides.

They are asked to close their eyes and maintain balance for about 20-30 seconds.

The examiner observes for swaying, loss of balance, or falling.

MSE: Attention and orientation

Observe the patient’s alertness

Spelling a word backwards

Counting backwards from 20

Auditory vigilance (Ex. ask to raise your hand)

(To check orientation) Current whereabouts (“do you know where are you rn?”), time (“what year it is rn?”)

Damage: Contralateral neglect, anosognosia

Why MSE test attention first?

If you have a problem with this (like not knowing where you are), it’ll affect every test you do.

Regions involved in MSE attention and orientation

Focal cortical and subcortical regions

Origin may be diffused (e.g. toxin)

Contralateral neglect

Inability to draw their attention to the left side of the world, and it’s not sensory impairment. (Drawing test, or not eating the food on the left side on the plate)

Most likely, Right parietal lobe damage (so while left hemisphere mostly controls the language aspect, the right hemisphere mainly controls attention!)

Anosognosia

Failure of individual to self-reflect that they have a disorder/dysfunction

(ex. seen in many Schizophrenic patients—they don’t realize that they’re hallucinating)

Usually goes away in a couple of months

Often caused by damage to the right parietal lobe, affecting self-awareness and perception.

Not the same as denial! They’re not aware, not refusing to accept it

MSE: Language

Fluency

Naming

Repetition

Prosody: Stress in speech

Comprehension

Reading

Writing

Damage: Praxis: “Pick up a pen to pretend that to be a knife, and slice a cheese” The dysfunction in this, they can’t do it according to the instruction

Regions involved in MSE language

Broca’s area: Speech production (motor planning structure)(in temporal lobe)

Wernicke’s area: Speech comprehension (in frontal lobe)

Praxia

The ability to pretend that an object and do another role

“Pick up a pen to pretend that to be a knife, and slice a cheese”

The dysfunction in this (apraxia), they can’t do it according to the instruction

Receptive aphasia

Wernicke’s aphasia: Fluent, Comprehension impairment, Nonsense speech. Also problems comprehending their speech and other ppl’s speech

Expressive aphasia

Broca’s aphasia: If the broca is broken, then no words are spoken!.

Not fluent, No comprehension impairment, Affects speech production, making speech slow, labored, and grammatically limited. No comprehension impairment

Global aphasia

Not fluent, Dysfunction in both speech production AND speech comprehension. “Tunnel tunnel tunnel tunnel tunnel tunnel tunnel”

Why can the guy in the video can count 1-10, but can’t say any other things else than tunnelๆๆๆ? Cuz it’s smth we learn to do since a very young age, and this shows how basal ganglia works!—habits and skills

Alexia

Problem with reading. After brain injury

Agraphia

Problem with writing. After brain injury

MSE: Memory

Digit span 1-9 (>5 digits, you’re fine)

Pointing span: Point to different corners of the room, then ask the patient to point to those corners in order

Verbal, visual object learning

Past public/personal events

Factual knowledge

Regions involved in MSE memory

Medial temporal structures (ex. hippocampus), thalamus, basal forebrain (Alzheimer’s), prefrontal cortex (ex. pointing span)

MSE: Visuospatial function

Line cancellation: Cross through all the lines you see

Copy geometric designs

Judgment of line orientation

Object/face/color recognition

Damage: Agnosia, prosopagnosia

Region involved in MSE visuospatial function

Ventral side of temporal lobe (e.g. fusiform gyrus) — damage: birdwatchers can’t recognize diff types of birds anymore

Agnosia

Inability to recognize or interpret sensory information, despite having intact sensory functions (e.g., normal vision or hearing)

Prosopagnosia

Failure to recognize faces

MSE: Executive functions

Ability to multi-task, adjust ur thoughts and behaviors accordingly, make decisions for long-term outcomes, etc.)

Judgment (ex. If you see an envelope on the side of the road, next to the mailbox, they can’t judge what to do with the letter) (Ex. Misjudgment that you shouldn’t go for your friend’s crush)

Cognitive/behavioral flexibility

• Luria 3-step (fist-edge-palm on the table repeatedly—test flexibity)

• Drawing loops (like drawing 8), alternating patterns

• Oral trail making test (A1, B2, C3, D4)

Perseverative behavior

Inflexibility. When a person gets "stuck" on a response and has difficulty shifting to something new

Glasgow Coma Scale (GCS)

A clinical tool developed at the University of Glasgow. It provides a practical method for assessing a patient's level of consciousness in response to defined stimuli

GCS: Purpose and usage

Assessing Severity: Determining the extent of a patient's neurological impairment.​

Monitoring Progress: Tracking changes in consciousness over time.​

Guiding Treatment Decisions: Informing medical interventions based on the patient's responsiveness

GCS: Evaluating three specific responses

Eye Opening (E) (4 scales): Assesses arousal and awareness.​

Verbal Response (V) (5 scales): Evaluates coherence and orientation.​

Motor Response (M) (6 scales): Measures purposeful movement and response to stimuli.​

GCS: Eye Opening (E)

4: Spontaneous

3: To sound​

2: To pressure

1: None

Verbal Response (V)

5: Orientated​

4: Confused​

3: Words​

2: Sounds​

1: None​

Motor Response (M)

6: Obeys commands​

5: Localizes pain: Moves hand toward pain source

4: Normal flexion (withdrawal)​: Withdraws from pain, but not directed

3: Abnormal flexion​: Arms bend abnormally across the body

2: Extension: Arms extend rigidly

1: None

GCS: Interpretation of scores

13-15: Mild brain injury

9-12: Moderate brain injury

8 or less: Severe brain injury

A lower GCS score means…

A deeper level of unconsciousness and a more severe brain injurt

GCS: Structured assessment approach (4 steps)

1. Check: Identify any factors that might interfere with the assessment (e.g., sedation, paralysis).​

2. Observe: Look for spontaneous behaviors in eye opening, verbalization, and movements.​

3. Stimulate: Apply verbal and physical stimuli if there is no spontaneous behavior.​

4. Rate: Assign scores based on the observed responses.​