Neuro Basics and Examination

Frontal lobe lesion: “on top of” everything

• Aphasia: Broca’s (when affected)

• Controls plan, programming, movement

• Emotional, behavior control, personality

• Olfaction

Temporal lobe lesion:

• Hearing and language comprehension

• Aphasia: Wernicke’s (when affected)

BROCA’s aphasia:

• Broken speech

• Expressive aphasia

• Non-fluent aphasia

• Lobe: Frontal lobe

• Treatment: Yes/No questions

WERNICKE’s aphasia:

• Unable to understand

• Receptive aphasia

• Fluent aphasia
  • Word salad

• Lobe: Temporal lobe

• Treatment: Gestures/demonstrations

Parietal lobe lesion:

• Perceptual disorders: e.g. unilateral neglect

• Sensory loss

Occipital lobe lesion:

• visual loss

A patient presents with speech difficulties, such that their speech is slow and laborious. The patient will frequently omit small grammatical words, such as "is" and "the," while speaking. However, they seem to understand spoken language quite well. Based on this information, what is the MOST LIKELY location of lesion?

A. Frontal lobe

B. Parietal lobe

C. Temporal lobe

D. Occipital lobe

location of CN 1 & 2:

cerebrum

location of CN 3 & 4:

mid brain

location of CN 5, 6, 7, 8:

pons

location of CN 9, 10, 11, 12:

medulla

CN I: Olfcatory

• Type: Sensory

• Function: Sense of smell

• Affected: Anosmia

CN II: Optic

• Type: Sensory

• Function: Vision: Color, acuity, peripheral vision, Pupillary Light Reflex

• Affected: Blindness, myopia, presbyopia

Pupillary Light Reflex:

Shine light in left eye:

• both constrict

  • Right CN 3 affected

• Only right constricts, left does not constrict:

  • Left CN 2 affected

During assessment of pupillary light reflex, when the light is shone into the left eye, the left pupil constricts, and the right pupil remains dilated. What is the MOST LIKELY explanation for these findings?

A. Right optic nerve damage
B. Left optic nerve damage
C. Right oculomotor nerve damage

D. Left oculomotor nerve damage

C. Right oculomotor nerve damage

CN III: Oculomotor nerve

Type : motor

Function:

• Movement of eyeball

  • If affected: strabismus - lateral

• Opens eyelids

  • If affected: ptosis - drooping of eyelids

• Constricts pupils

  • If affected: dilation

CN IV: Trochlear nerve

CN VI: Abducens nerve

A patient presents with a lesion to the glossopharyngeal and vagus nerve. Based on the location of the lesion, which other cranial nerve is MOST LIKELY to be affected?

A. Vestibulocochlear nerve

B. Spinal Accessory nerve

C. Facial nerve

D. Trigeminal nerve

B. Spinal Accessory nerve

CN V: Trigeminal nerve

• mixed nerve

• sensation to face

• corneal reflex - afferent

• sensation to anterior 2/3 of tongue

• dampens sounds

• jaw jerk

CN VII: Facial nerve

• mixed nerve

• movement of face

• corneal reflex - efferent

• taste to anterior 2/3 of tongue

• dampens sound

• lacrimation, salivation

A patient presents to a TMJ specialist for jaw pain. On examination, there is weakness of the masseter and temporalis muscles on the same side, and their jaw deviates to the right when they open their mouth. Sensory examination reveals reduced sensation over the right lower jaw and chin. Which of the following functions is MOST LIKELY impaired along with this presentation due to the nerve damage described?

A. Smiling
B. Chewing
C. Swallowing
D. Moving tongue

B. Chewing

CN VIII: Vestibulocochlear nerve

• sensory

• balance and hearing

Steps to diagnose hearing loss: Know the type of hearing loss and side

• Step 1: Rinne’s test » for type - (conductive or sensorineural)

• Step 2: Weber’s test » for the side - (right vs left)

Rinne Test → normal

air conduction > bone conduction

Rinne Test → sensorineural loss

air conduction > bone conduction

Rinne Test → conduction loss

bone conduction > air conduction

Weber Test → normal

heard equal on both sides

Weber Test → sensorineural loss

heard louder in normal ear

Weber Test → conduction loss

heard louder in affected ear

Use CANS for Weber’s:

- Conductive--------- Louder to AFFECTED ear

- Sensorineural ----- Louder in NORMAL ear

A patient reports experiencing mild hearing loss since that past few months. Rinne’s test was consistent with bone conduction greater than air conduction on both sides. Weber’s test findings show sound was louder in the left ear. Which of the following is MOST APPROPRIATE?

A. Right side sensorineural hearing loss

B. Left side conduction hearing loss
C. Right side conduction hearing loss

D. Left side sensorineural hearing loss

B. Left side conduction hearing loss

CN IX: Glossopharyngeal nerve

• mixed

• gag reflex: afferent

• posterior tongue sensation and taste

CN X: Vagus nerve

• mixed

• gag reflex: efferent

• deviation of uvula

CN XII: Hypoglossal nerve

• motor

• moves tongue

A patient presents with concerns of difficulty speaking and swallowing. Upon examination, the physical therapist notes that the patient’s tongue deviates to the right when protruded, and there is noticeable atrophy of the right side of the tongue. What is the MOST LIKELY diagnosis related to the findings observed in this patient, and which cranial nerve is primarily affected?

A. Right-sided glossopharyngeal nerve (CN IX) lesion

B. Left-sided hypoglossal nerve (CN XII) lesion
C. Right-sided hypoglossal nerve (CNXII) lesion
D. Left-sided facial nerve (CN VII) lesion