Brainstem Part I Flashcards
Which of the following is considered a key function of the brainstem? Select all that apply.
mediating levels of arousal
motor and sensory functions of the head and neck
pain modulation
regulating homeostatic functions
maintaining postural control and balance
mediating levels of arousal
motor and sensory functions of the head and neck
pain modulation
regulating homeostatic functions
maintaining postural control and balance
Explanation
The brainstem plays important roles in many functions. Key functions include: mediating levels of arousal, maintaining postural control and balance, modulation of pain signals, regulating homeostatic functions, motor and sensory functions of the head and neck, and the mediation of brainstem reflexes (not indicated above).
Which of the following structures is an important landmark of the midbrain?
tectum
olive
pyramid
tectum
Explanation
The tectum is an important landmark of the midbrain. It contains the superior and inferior colliculi. The pyramids and the olive are important structures of the medulla.
Which structure would you locate to find the exit points of cranial nerves IX, X, XI, and XII?
pyramids
colliculi
olive
olive
Explanation
The olive is an important landmark for the exit points of several CNs. CN XII will exit from the preolivary sulcus of the medulla and CN IX, X, & XI will exit from the postolivary sulcus of the medulla.
Which structure contains the corticospinal tract? Select all that apply?
pyramids
olive
basilar pons
crus cerebri
superior colliculi
basilar pons, crus cerebri, pyramids
Explanation
The corticospinal tract will travel from the cortex to the spinal cord by passing through key locations in the brainstem. It will travel in the crus cerebri of the midbrain, the basilar pons, and the medullary pyramids.
Which of the following tracts crosses in the medulla? Select all that apply.
corticospinal tract
posterior columns-medial lemniscus
anterolateral system
corticospinal tract & posterior columns-medial lemniscus
Explanation
The majority of the corticospinal tract will cross to the other side after exiting the medullary pyramids in the caudal medulla. The crossed fibers become the lateral corticospinal tract and the uncrossed fibers become the anterior corticospinal tract. The posterior columns will synapse with a second neuron in their respective nuclei (gracile and cunate nuclei) and then cross to the other side in the medulla (sensory decussation) becoming the medial lemniscus on the other side. The anterolateral system crosses at the level of the spinal cord.
An injury to the corticospinal tract above the level of the motor decussation (crossing of fibers) will result in motor impairments ipsilaterally.
True or False
False
Which of the following nuclei will process pain and temperature information from the face?
principle sensory
spinal trigeminal
vestibular
solitary
Which of the following is a sensory nucleus? Select all that apply.
spinal trigeminal
nucelus ambiguus
edinger-westphal
solitary
cochlear
spinal trigeminal
Explanation
The spinal trigeminal nucleus is considered part of the trigeminal system. It will process pain and temperature information from the face, The principle sensory nucelus will process touch, pressure, vibration, and proprioception from the face; the vestibular nucleus is a special sensory nucleus of the vestibular system; the solitary nucleus will be processing viscerosensory information, including taste.
Which of the following nuclei are associated with the facial nerve? Select all that apply.
superior salivatory
inferior salivatory
facial motor
nucleus ambiguus
soliary
superior salivatory, facial motor, soliary
Explanation
The facial nerve is a mixed cranial nerve that carries somatic and visceral sensory and motor information. The superior salivatory nucelus is its viscermotor nucleus; the facial motor nucleus is its somatic motor nucleus; the solitary nucelus is its viscerosensory nucleus and the nuceli of the trigeminal system (not indicated above) is its somatic sensory nucleus.
Which cranial nerves exit at the pons-medullary junction?
CN III & IV
CN VI, VII, & VIII
CN IX, X, & XI
CN VI, VII, & VIII
Explanation
The abducens (VI), facial (VII) and vestibulocochlear (VIII) nerves will exit from the pons-medullary junction. The oculomotor (III) and trochlear (IV) exit from the midbrain. CN IX, X, XI exit from the postolivary sulcus of the medulla.
Which of the following is a sensory nucleus? Select all that apply.
spinal trigeminal
nucelus ambiguus
edinger-westphal
solitary
cochlear
spinal trigeminal, solitary, cochlear
Explanation
The spinal trigeminal (somatic), soliary (visceral), and cochlear (special sensory) are all sensory nuclei. The nucleus ambiguus (somatic) and the edinger-westphal nucleus (visceral) are motor nuclei.
