Term
The mastication cycle lasts about this long. |
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Definition
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Term
What are the three phases of the mastication cycle? |
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Definition
Closing, Occlusal, Opening |
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Term
T/F: The jaw closing reflex is monosynaptic. |
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Definition
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Term
Afferents in the jaw closing reflex travel to this region of the brainstem before synapsing on the trigeminal motor nucleus. |
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Definition
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Term
Where do afferents first synapse in the jaw opening reflex? Where do the 2nd order neurons synapse? |
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Definition
Spinal trigeminal nucleus; Trigeminal motor nucleus
[image] |
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Term
What aspect of reflexes undermine the reflex theory of mastication? |
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Definition
They are extremely fast, yet mastication takes 1sec. |
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Term
How was curare used to disprove the reflex theory of mastication? |
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Definition
Administering curare would abolish reflexes but efferect patterns of mastication continued (could still chew even though afferents were not functioning). |
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Term
List the two components of the central pattern generator? |
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Definition
1. Rhythm generator
2. Burst generator |
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Term
Output from the central pattern generator is sent to this structure. |
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Definition
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Term
This component of the masticatory pathway is responsible for turning the process on. |
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Definition
Cortex; Recall the story of the baby in the highchair chewing. Chewing ceased when the baby fell asleep and resumed again when the baby awoke. |
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Term
What is the role of the rhythm generator? |
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Definition
To establish the overall length of the cycle
[image] |
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Term
What is the role of the burst generator? |
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Definition
To establish the duration and pattern within the cycle.
[image] |
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Term
What is the purpose of the motor nucleus? |
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Definition
To drive the individual muscles. |
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Term
What is the purpose of the jaw muscles? |
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Definition
To convert the neural signals into force. |
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Term
Evidence for rhythm generator includes:
1. Correct anatomical projections from ________.
2. Electrical stimulation of cortex leads to ________.
3. That stimulation can be ________ or regular.
4. ________ abolish rhythmic activity.
5. Rhythmic activity seen in ________ animal. |
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Definition
Cortex; Rhythmic activity; Random; Lesions of pathway; Paralyzed |
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Term
List the two nuclei of the rhythmic generator and whether or not they are rhythmic. |
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Definition
Nucleus reticularis paragigantocellularis (not rhythmic); Nucleus reticularis gigantocellularis (rhythmic) |
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Term
T/F: Innervation of the rhythm generator is unilateral. |
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Definition
False. Each rhythm generator controls several places, inluding coordinating with the contralateral side. |
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Term
What aspect of muscle control gives evidence for the central pattern generator being a separate structure within the brain? |
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Definition
They can fire voluntarily or involuntarily. |
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