quiz 2 Flashcards
where do the cranial nerves originate?
in the brainstem
I-IV= midbrain V-VIII= pons IX-XII= medulla
where do CNs receive impulses from?
the corticobulbar tract
describe CNS
- LMNs
- some are motor only, sensory only, or sensory and motor
- innervate mms of the jaw, face, pharynx, larynx, soft palate, tongue, and neck
On old olympus’ towering tops a fair armed goddess viewed some hops
I-Olfactory II-Optic III-Oculomotor IV-Trochlear V-Trigeminal VI-Abducens VII-Facial VIII-Auditory IX-Glossopharyngeal X-Vagus XI-Spinal Accessory XII-Hypoglossal
Some say marry money, but my brother says big brains matter most
S= sensory M= motor B= both
CNs of speech production
Trigeminal (V) B Facial (VII) B Glossopharyngeal (IX) B Vagus (X) B Spinal Accessory (XI) M Hypoglossal (XII) M
CN I (olfactory)
- only tested when frontal lobe tumor is suspected
- maybe damaged in pts with closed head injuries, nasal obstruction, viral infections and can be abnormal in PD, Alzhiemers, and MS
How to test CN I
test by asking if pt can smell, vanilla or cinnamon in each nostril
CN II (Optic)
- visual acuity (test with hand card)
- color vision (loss of color esp RED is important symptom of optic neuritis)
- visual fields (can be tested by counting fingers in each quadrant)
- visual extinction (to detect neglect)
CNs III, IV, VI (oculomotor, trochlear, and abducens)
-control eye movement and pupil diameter
CN V (trigeminal)
-facial sensation and mms of mastication
how to test CN V
- palpate the masseter mms as the pt bites down hard
- open mouth an resist the examiners attempt to close mouth
- jaw jerk or reflex
CN VII (facial)
- has 2 major branches for upper and lower face
- lower face receives unilateral innervation from the contralateral side of the brain
- upper face received bilateral innervation from right and left corticobulbar tracts
how to test VII
-look for asymmetry of facial shape, smile, puff out cheeks, clench their eyes tight, wrinkle brow, check taste
UMN lesions cause..
contralateral facial weakness sparing the forehead
LMN lesions cause..
weakness involving the whole ipsilateral face
CN VIII (auditory)
- sensory
- originates in inner ear
- vestibular branch carries impulses for balance
- cochlear branch carrier impulses for hearing
CN IX (glossopharyngeal)
- innervates stylopharyngeus mms which assists in elevation of the pharynx and larynx
- plays a role in resonance and phonation by shaping the pharynx
- contributes to gag reflex
- does not innervate an isolated function so is tested with CN X
CN X (vagus)
means WANDERER
-long nerve with many branches serving various parts of the body: larynx, intestines, heart, and velum
3 branches of CN X important to speech
- pharyngeal nerve branch
- external superior laryngeal nerve branch
- recurrent nerve branch
how to test CN x/IX
- does the palate elevate symmetrically when the pt says AH
- does the pt gag when the posterior pharynx is brushed?
- palate elevation and the gag reflex are impaired in lesions involving IX or X, the neuromuscular junction or the pharyngeal mms
CN XI (spinal accessory)
- major function is to help turn, tilt, and thrust the head forward
- supplies innervation for the trapezius and sternocleidomastoid
- related to POSTURE for speech and feeding
testing CN XI
- put your hands on the sides of your patients head
- tell the patient to move his head from side to side
- apply only light pressure when the head is moved
CN XII (hypoglossal)
- provides motor innervation for all intrinsic mms of the tongue and MOST extrinsic
- supplies mms of tongue and surrounding the hyoid bone and contribute to swallowing and speech
testing CN XII
- stick out tongue and move from side to side
- strength can be tested by having the pt push the tongue against a tongue blade
- p^t^k^
CN XII things to note when testing
- atrophy or fasiculations of the tongue while at rest (indicative of LMN lesions)
- when pt sticks tongue out straight, does it curve?
- unilateral tongue weakness causes the tongue to deviate toward the WEAK side
CN V, VII, IX, and XIII testing
- is the pts speech hoarse, slurred, quiet, breathy, nasal, low or high pitched?
- abnormal articulation of speech can occur in lesions involving the mms of arctic, the neuromuscular junction, or the peripheral or central portions of CN V, VII, IX, and XIII
