What are the three main functions of the brainstem?
- conduit (information goes to cortex and spinal cord) 2. cranial nerves 3. integrative (complex motor patterns)
Where do you find the superior colliculus? What is its role?
rostral midbrain role: visual
Where do you find the inferior colliculus? What is its role?
caudal midbrain role: auditory
Where do the rootlets for CN XII exit?
CN XII rootlets exit between the olive and the pyramid (preolivary sulcus)
What are some distinguishing characteristics of the caudal medulla?
- central canal 2. gracilis and cuneate nuclei & tracts 3. internal arcuate fibers form medial lemniscus 4. pyramidal decussation
What are some distinguishing characteristics of the rostral medulla?
- fourth ventricle 2. inferior olivary nuclei 3. XII rootlets often visible 4. internal arcuate fibers from IO to ICP 5. pyramids
What are some distinguishing characteristics of the caudal pons?
- Inferior cerebellum peduncle: mostly within cerebellum at this level 2. Middle cerebellar peduncle attaches pons to cerebellum 3. ML: horizontal with feet lateral (compare to rostral medulla) 4. Fourth ventricle present
What are some distinguishing characteristics of the rostral pons?
- Superior cerebellar peduncle 2. ML: horizontal with feet lateral, approaches STT 3. Small ventricle space: at opening of aqueduct
What are some distinguishing characteristics of the caudal midbrain?
- Inferior colliculi 2. IV 3. Decussation of SCP
What are some distinguishing characteristics of the rostral midbrain?
- Superior colliculi 2. III 3. Red nucleus 4. Substantia nigra
Which of the following is in the rostral midbrain? A) Red nucleus B) Superior colliculi C) Substantia nigra D) Oculomotor nucleus E) All the above
E) all of the above
Which of the following is in the pons? A) Middle cerebellar peduncle B) Inferior olivary nuclei C) Cerebral aqueduct D) Pyramidal decussation E) Gracile nuclei
A) middle cerebellar peduncle
Which of the following is in the caudal medulla? A) Inferior cerebellar peduncle B) Middle cerebellar peduncle C) Pyramidal decussation D) Hypoglossal nerve nucleus E) Inferior olivary nuclei
C) pyramidal decussation
What separates sensory and motor nuclei in the brainstem and spinal cord?
sulcus limitans
Which cranial nerves have motor axons for somatic skeletal muscle, somatic motor fibers?
CN III, IV, VI, XII
Which cranial nerves are special sensory?
CN I, II, VIII
Which cranial nerves are branchiomeric?
CN V, VII, IX, X, and XI
What section of the brainstem does this image come from?
caudal midbrain
What section of the brainstem does this image come from?
rostral midbrain
What section of the brainstem does this image come from?
rostral pons
What section of the brainstem does this image come from?
caudal pons
What section of the brainstem does this image come from?
caudal medulla
What section of the brainstem does this image come from?
rostral medulla
