Exam 2 Cranial Nerves Flashcards
olfactory nerve
sensory, olfaction.
how does a lesion of the olfactory nerve present
inability to smell
what happens with the olfactory nerve, and how can we smell
the olfactory cortex, goes to the insula of the temporal lobe, and amygdala and parahippogyrus, and then we can make decisions, it can have declarative memories and can give us an emotional or hunger response.
what are special about the first two cranial nerves
they have no peripheral components. They are surrounded with oligodendrocytes, so they are affected by diseases like MS.
what is the optic nerve
sensory, vision. AFFERENTS for the pupillary and ciliary (accommodation).
what does a lesion of the optic nerve look like
impaired pupil constriction and accommodation.
how do we test the optic nerve
equity, eye chart, and also light in the pupil
oculomotor nerve
motor and parasympathetic
what is the motor component of the oculomotor nerve
superior, inferior and medial rectus, and the inferior oblique. also levator palpebrae, and EFFERENTS for VOR.
what happens to the motor component of the oculomotor with a lesion
unable to move the eye, up down and medially. the eye will deviate inferiorly and lateral, and the eye lid with droop. and nystagmus
what is the parasympathetic portion of the oculomotor nerve
sphincter of pupil, ciliary of the lens, and the EFFERENT for pupillary and accommodation.
what happens to the parasympathetic component of the oculomotor with a lesion
pupil dilation and blurred vision because of the loss of accommodation.
trochlear nerve
motor to the superior oblique and the EFFERENT for the VOR
what happens with a lesion to the trochlear nerve
hard time moving the eye, and diplopia.
trigeminal nerve
sensory and motor
what is the sensory part of the trigeminal nerve
somatosensation of the face, TMJ, and AFFERENT for the corneal reflex.
what happens if there is a lesion in the sensory part of the trigeminal nerve
trigeminal neuralgia, and loss of tactile sensation of the face.
what is the motor part of the trigeminal nerve
muscles of mastication (masseter, pterygoids, temporalis)
soft palate (tensor veli palatine)
throat (digastric and mylohyoid)
middle ear (tensor tympani)
what happens with a lesion to the motor part of the trigeminal nerve
weakness in biting or chewing, jaw jerk reflex
what does a jaw jerk reflex reflect
and UMN lesion. but not the L or the R.
how can we test the motor component of the trigeminal
have them chew, and clench and open, and look for deviations because of the pterygoids
if there is weakness in the pterygoid, there will be deviation to the
side of weakness.
describe the path of light touch in the trigeminal ganglia.
1: main sensory nucleus of the pons,
2: decussates, then to VPM thalamus
3: somatosensory cortex.
describe the path of nocioception on a delta and c-fibers to the trigeminal ganglion
into the pons, descends as trigeminal nerve to the C-spine, then
1: spinal trigeminal nucleus
2: decussates, then to VPM thalamus
3: somatosensory cortex. .
abducens
motor to the lateral rectus and EFFERENT for VOR
what happens with a lesion to the abducens
eye deviates medially, diplopia.
what CN are involved in the VOR
3,4,6
what is the VOR
vestibulooccular reflex. ability to keep eyes on a moving target, so doll eyes
what components does the facial nerve have
motor sensory and parasympathetic
what is the sensory part of the facial nerve
taste from the anterior 2/3 tongue, sensation from the external ear and palate.
what happens with a lesion and loss of sensory part of facial
loss of taste on the anterior 2.3 tongue
what is the motor part of the facial nerve
muscles of facial expression and throat (digastric and mylohyoid) and middle ear.
what happens to lesions in the facial nerve, for motor
facial palsies
what is the parasympathetic function of the facial nerve
submandibular and sublingual glands, and lacrimal glands, and the glands of the nasal cavity and palate
what is the result of the facial lesion in parasympathetic
decreased tears and saliva production
vestibulocochlear nerve
sensory of hearing and balance
what happens with a lesion of the vestibulocochlear nerve
loss hearing, balance equilibrium, nausea, vomiting and vertigo
how can we test the vestibulocochlear nerve? what two tests
weber: tuning fork on forehead, can you feel or hear it equally on both sides.
Renee: place tuning fork on mastoid process, then move it away. neurosensation loss, the air is greater sound then on bone. Conductive loss, the bone is louder then air.
with conductive hearing loss, which side do you hear better on
the abnormal side.
what components does the glossopharyngeal nerve have
sensory, motor, parasympathetic and visceral
what are the sensory components of the glossopharyngeal nerve
pharynx, larynx, palatine tonsils, posterior tongue, middle ear, AFFERENT for gag and swallowing reflex
lesions in glossopharyngeal sensory part
loss of gag reflex
what are the motor parts of the glossopharyngeal
pharyngeal muscle- stylopharyngeus
lesion in the glossopharyngeal motor part
dysphagia, can’t swallow
what are the parasympathetic parts of the glossopharyngeal. and lesion
parotid gland, decreased salivation
what are the visceral components of the glossopharyngeal. and lesions
carotid body and sinus, decreased regulation of HR because of decreased input from the carotid blood pressure.
what components does the vagus nerve have
sensory, motor, parasympathetic and visceral
sensory part of the vagus nerve and lesion
interior pharynx, larynx, skin over external ear. decreased sensation
what is the motor part of the vagus, and lesions.
muscles of pharynx and larynx, so hard time swallowing, and uvula will deviate away from the dysfunction.
parasympathetic part vagus and lesions
efferents smooth muscles and glands in throat, pharynx, larynx, and thorax and abdomen. affects digestive activity, speech, bronchial constriction and regulating HR
what is the visceral part of the vagus, and its lesions
larynx, larynx, thorax and abdomen, lesions decrease AFF input to those areas.
if the left palate is touched, and you gag, and the Left palate rises higher then the right, and the uvula deviates to the L, where and in which nerves is there a lesion
right, 9 and 10
spinal accessory, and lesions
motor to the SCM and upper trap. hard time elevating ipsilateral scapula and rotating contralaterally.
hypoglossal and lesion?
motor to intrinsic and extrinsic tongue muscles, throat muscles (thyrohyoid, and geniohyoid).
lesions: protruded tongue will deviate to the side of the lesion.
