Brainstem Structure and Cranial Nerve Nuclei Flashcards
1
Q
Brainstem Components (3):
A
- Midbrain
- Pons
- Medulla
2
Q
What are the general areas of a brainstem cross section?
A
- The portion posterior to the ventricular space
- The portion anterior to the ventricular space
- Additional structures on the anterior surface
3
Q
Brainstem Functions:
Integrative functions
A
- performed by a diffuse nucleus within the core of the brainstem
- reticular formation
4
Q
Brainstem functions:
Reticular formation
A
- Helps regulate consciousness
- Respiratory & cardiovascular centers
5
Q
What is the brainstem’s role for the sensory and motor tracts?
A
- Serves as a conduit for ascending sensory and descending motor tracts
-
Corticospinal tract
- voluntary movement of limbs
- Spinothalamic tract
- transmits sensory information
- pain and temperature
- Posterior column / Medial lemniscus system
- transmits sensory information
- touch, vibration, pressure and proprioception
6
Q
Brainstem functions:
Cranial Nerves
A
- Cell bodies of neurons clustered in “nuclei” throughout the brainstem
- origins of motor CNs
- terminations of sensory CNs
- Nuclei are bilateral
- CN Nuclei are arranged in functional columns
7
Q
Describe briefly how the nervous system develops:
A
- NS develops from neural tube
- Neural tube has basal plate (motor) and alar plate (sensory)
- divided by sulcus limitans
- Brainstem development is similar to spinal cord development
8
Q
Brainstem Nuclei:
Somatic Motor (Red)
- Function
- Brainstem Nuclei ⇒ CNs
A
- Function: Innervate skeletal muscles in the head and neck that are derived from myotomes
- Oculomotor ⇒ CN III
- Trochlear ⇒ CN IV
- Abducens ⇒ CN VI
- Hypoglossal ⇒ CN XII
9
Q
Brainstem Nuclei:
Branchial Motor (orange)
- Function
- Brainstem Nuclei ⇒ CNs
A
-
Function: Innervate skeletal muscles derived from branchial arches
- muscles of mastication, facial expression, pharynx, larynx, middle ear, trapezius m.
- Motor nucleus of V ⇒ CN V
- Facial nucleus ⇒ CN VII
- Nucleus ambiguus ⇒ CN IX and CN X
- Spinal Accessory nucleus ⇒ CN XI
- Located in spinal cord
10
Q
Brainstem Nuclei:
Visceral Motor (Yellow)
- Function
- Brainstem nuclei ⇒ CNs
A
- Fucntion: Preganglionic parasympathetic innervation to cardiac m., smooth m. and glands
- Edinger-Westphal ⇒ CN III
- Salivatory ⇒ CN VII
- Inferior Salivatory ⇒ CN IX
- Dorsal motor nucleus of X ⇒ CN X
11
Q
Brainstem Nuclei:
Visceral Sensory (Green)
- Function:
- Brainstem nuclei ⇒ CNs
A
-
Function:
- Special – Taste
- Rostral Nucleus solitarius (gustatory nucleus) ⇒ CN VII, IX and X
-
Function:
- General – Control of cardiorespiratory and digestive functions
- Caudal nucleus solitarius (cardiorespiratory nucleus) ⇒ CN IX & CN X
12
Q
Brainstem Nuclei:
Somatic Sensory (Blue)
- Function:
- Brainstem nuclei ⇒ CNs
A
- Function: Convey touch, pain, temperature, position and vibration from skin, muscles and joints of the head
- Trigeminal nuclei ⇒ CN V, VII, IX and X
13
Q
Brainstem Nuclei:
Special Sensory (Purple)
- Function:
- Brainstem nuclei ⇒ CNs
A
-
Function:
- Hearing
- Cochlear nucleus ⇒ CN VIII
-
Function:
- Balance
- Vestibular nuclei ⇒ CN VIII
14
Q
Caudal Midbrain
A
- Cerebral aqueduct
- Raphe nuclei
- Trochlear nucleus
- Trochlear nerve fibers, on their way to the contralateral superior oblique
-
Inferior colliculus
- Site of termination of the lateral lemniscus and site of origin of the brachium of the inferior colliculus
- Lateral lemniscus ending in the inferior colliculus
- Anterolateral pathway
- Medial lemniscus
- Cerebral peduncle
- Substantia nigra
- Decussation of the superior cerebellar peduncles (DSCP)
- Pontine nuclei
- Central tegmental tract
- Medial longitudinal fasciculus (MLF)
- Mesencephalic trigeminal tract
- Periaqueductal gray
15
Q
Rostral Midbrain (level of superior colliculus)
A