2.1 Neurology of Swallowing Flashcards
What cranial nerves do we have to know?
5
- Trigeminal (V)
- Facial
- Glossopharyngeal
- Vagus (X)
- Hypoglossal
.
Are motor/efferent nerves ascending or descending?
Descending
Are sensory/afferent nerves ascending or descending?
Ascending
What is important to know about the ophthalmic branch of the trigeminal nerve?
(2)
Sensory
Not involved in swallowing
What is important to know about the maxillary branch of the trigeminal nerve?
(2)
Sensory
Upper lip, maxillary teeth and palate
.
What is important to know about the mandibular branch of the trigeminal nerve?
(4+4)
Sensory: Anterior 2/3rd of tongue, mucous membranes of mouth/cheek, gums, TMJ
Motor: Masticatory muscles, Tensor veli palatini, mylohyoid and anterior belly of digastric.
.
What are the mastication muscles?
4
Masseter
Temporalis
Lateral pterygoid
Medial pterygoid
.
What does the trigeminal nerve guide and control?
The mastication process
What part of the tongue is the trigeminal nerve responsible for?
responsible for the sensation of the general anterior 2/3rds of the tongue
What branch is responsible for the sensation of the facial nerve?
Chorda Tympani branch (taste anterior 2/3rd of the tongue)
What motor movements is the facial nerve responsible for?
2
Temporal, Zygomatic: Not involved in swallowing
Lip sphincter: Buccal, Mandibular and cervical
.
In regards to SENSATION, what are the two visceral afferents of the glossopharyngeal nerve?
(2)
Taste sensation from the posterior third of the tongue
The mucous membranes of part of the tongue, tonsil, and upper pharynx
.
In regards to the MOTOR movements, what is the special visceral efferent of the glossopharyngeal nerve?
Stylopharyngeus
.
What constrictors are controlled by the glossopharyngeal nerve?
pharyngeal constrictors
In regards of the vagus nerve, what does the internal branch of the SLN provide sensation for?
(3)
Vallecular mucosa
General hypopharynx
Larynx
.
What does the vagus nerve provide motor movements for?
4
velum
Pharynx
Larynx
Esophagus
.
What tongue muscles does the hypoglossal nerve provide motor movements for?
all tongue muscles except the palatoglossus
In regards to brainstem control, sensory information from the pharynx is relayed by afferent fibers which terminate where?
In the nucleus of the tractus solitarius (NTS) in the medulla
In regards to brainstem control, sensory information can also be sent by afferent fibers to where?
Also, where does this begin?
different regions of the cerebrum
This begins the cortical response to swallowing
What is the nucleus ambiguous (NA) in the medulla?
2
the principle motor nucleus
Provides input to the cranial nerves
What brodmann area is the primary motor cortex?
Area 4
What brodmann area is the premotor cortex?
Area 6
What is the first step of the Volitionary Pathway (1)?
Sensory information reaches the somato-sensory cortex via the thalamus
What is the second step of the Volitionary Pathway (1)?
2
Sensory information from the Somatosensory areas are relayed to the motor cortex
Then motor commands are initiated.
What is the third step of the Volitionary Pathway (1)?
Motor commands reach the periphery through cortico-bulbar pathways.
What is the first step of the Reflexive Pathway (2)?
Sensory information reaches the nucleus tractus solitarius (NTS)
What is the second step of the Reflexive Pathway (2)?
Sensory information from the nucleus tractus solitarius (NTS) is relayed to the reticular formation system and in turn to nucleus ambiguous (NA)
.
What brain activation are involved in swallowing?
10
Inferior precentral gyrus – bilaterally
Primary somatosensory area (BA 43)
Right Premotor cortex
Right Precentral Gyrus
Right Anterior Insula
Left cerebellum
Basal ganglia
Thalamus
Right temporal gyri
Right inferior parietal lobe
.
What is the third step of the Reflexive Pathway (2)?
Motor commands modulated by nucleus ambiguous (NA) reach the periphery.
Where is the insula lobe located?
Located beneath the juncture of frontal, temporal, and parietal lobes
What does the insula lobe coordinate?
1+3
Interaction of …
Oral musculature
Gustation (taste)
Alimentary tract (digestion)
.
What does the insula connect to?
4
Primary motor cortex
Supplementary motor cortex
Thalamus
Nucleus tractus solitarii (NTS)
.
What does lesions of the right anterior insula do?
2
Reduced sensory input causes delayed swallow
Decreased sensory input – taste, volume, temperature
What does the cerebellum connect?
4
Primary motor cortex
Supplemental motor cortex
Brainstem
Thalamus
.
What is the cerebellum an intensifier of?
Intensifier of responses
What is the purpose of the cerebellum?
3
Timing
Coordination
Sequencing
What does the cerebellum integrate? (3)
What does this do?
Proprioceptive info
Vestibular info
Motor planning
Create smooth movements.
