Chart — Neurology
Cranial Nerve Assessment Chart
All 12 cranial nerves at a glance — function, bedside assessment test, and clinically important abnormal findings for each cranial nerve.
Data Source: Clinical Neurology / Bates' Guide to Physical Examination
Educational use only. Cranial nerve findings must be interpreted in clinical context and escalated per institutional protocol. This material supports nursing education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional policy, or medical direction. Always follow facility protocols and current provider orders.
Type key:S = Sensory, M = Motor, B = Both. Memory: “Some Say Marry Money But My Brother Says Big Brains Matter More” (CN I–XII).
Complete Assessment Chart
| CN | Name | Type | Function | Bedside Test | Abnormal Finding |
|---|---|---|---|---|---|
| I | Olfactory | S | Smell | Identify common scent (coffee, vanilla) with one nostril occluded | Anosmia — head trauma, olfactory groove tumor, COVID-19 |
| II | Optic | S | Vision | Visual acuity; visual fields to confrontation; pupillary afferent (RAPD) | Vision loss, visual field cut, papilledema (elevated ICP) |
| III | Oculomotor | M | Eye movement (up, down, medial), eyelid, pupil constriction | Follow finger in H-pattern; pupil reactivity; eyelid droop (ptosis) | Fixed dilated pupil; ptosis; eye down-and-out — CN III palsy or UNCAL HERNIATION |
| IV | Trochlear | M | Superior oblique — eye rotates down and inward | Look down and inward; vertical diplopia when descending stairs? | Vertical diplopia — most common after head trauma |
| V | Trigeminal | B | Facial sensation (V1/V2/V3); jaw movement (mastication) | Light touch + pinprick to all three facial divisions; corneal reflex; jaw clench | Facial numbness; absent corneal reflex; jaw deviation toward lesion |
| VI | Abducens | M | Lateral rectus — abducts eye outward | Track finger to far lateral gaze; assess for inability to cross midline laterally | Cannot abduct eye; diplopia on lateral gaze — EARLIEST CN sign of elevated ICP |
| VII | Facial | B | Facial expression; taste anterior 2/3 tongue; lacrimal/salivary glands | Smile; raise eyebrows; close eyes tight; puff cheeks; show teeth | Bell palsy: entire face (incl. forehead). Stroke: lower face ONLY (forehead spared) |
| VIII | Vestibulocochlear | S | Hearing (cochlear); balance/spatial orientation (vestibular) | Whisper test or finger rub; Weber + Rinne tuning fork tests; nystagmus assessment | Sensorineural hearing loss; tinnitus; vertigo; nystagmus |
| IX | Glossopharyngeal | B | Taste posterior 1/3 tongue; pharyngeal sensation; gag reflex afferent | Gag reflex (afferent limb); taste posterior tongue; assess swallowing | Loss of gag; dysphagia — always assess with CN X |
| X | Vagus | B | Pharynx/larynx (motor); gag reflex efferent; parasympathetic to heart/lungs/GI | Say 'aah' — uvula midline rise; voice quality; gag (efferent); swallowing | Uvular deviation away from lesion; hoarseness; absent gag; dysphagia |
| XI | Accessory | M | Sternocleidomastoid (neck rotation); trapezius (shoulder shrug) | Shoulder shrug vs. resistance; head turn vs. resistance each direction | Shoulder drop; weak neck rotation — neck surgery, lymph dissection, cervical cord injury |
| XII | Hypoglossal | M | Tongue movement | Protrude tongue and move side to side; assess for deviation, atrophy, fasciculations | Tongue deviates TOWARD lesion (peripheral). In stroke: deviates toward WEAK limb side. |
CN III and CN VI highlighted — most clinically critical for bedside neuro monitoring.
Type Summary
| Type | CNs | Notes |
|---|---|---|
| Sensory only | I, II, VIII | Carry afferent sensory signals to the brain only |
| Motor only | III, IV, VI, XI, XII | Carry efferent motor signals to muscles only |
| Both (sensory + motor) | V, VII, IX, X | Mixed nerves — carry signals in both directions |
Critical Findings to Escalate Immediately
| Finding | Likely Diagnosis | Urgency |
|---|---|---|
| New unilateral fixed and dilated pupil | Uncal herniation (CN III compression) | CODE — call immediately |
| Unilateral lateral gaze palsy (cannot abduct eye) | Elevated ICP (CN VI most sensitive) or brainstem lesion | Urgent — notify now |
| New facial droop + arm weakness | Stroke (CN VII + motor strip) | CODE STROKE — activate immediately |
| Absent gag + uvular deviation + dysphagia | Brainstem stroke or GBS (CN IX/X) | Urgent — airway at risk |
| Sudden onset of all bulbar symptoms (IX, X, XI, XII) | GBS, brainstem stroke, ALS exacerbation | Urgent — respiratory compromise likely |
| Sudden vision loss (CN II) | Central retinal artery occlusion, stroke, amaurosis fugax | Urgent — possible TIA/stroke harbinger |
Related Resources
Standards & sources
Fact-checked Jun 21, 2026This page is written to align with Clinical Neurology / Bates' Guide to Physical Examination. It is an educational summary, not a citation of any single document — always verify specific doses, values, and protocols against current guidelines and your facility policy. How we source content →