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Flashcards in Medullary Reflexes Deck (24)
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1
Q

What 2 centers control respiration?

A
  • Apneustic center

- Pneumotaxic center

2
Q

Where is the pneumotaxic center found?

A

In the pons

3
Q

Where is the apneustic center found?

A

In the medulla

4
Q

Which respiratory center sends stimulation to the inspiratory area?

A

Apneunstic

5
Q

Which respiratory center inhibits the inspiratory area?

A

Pneumotaxic

6
Q

Which respiratory center causes long deep breaths?

A

Apneustic

7
Q

Which respiratory center fine tunes respiration?

A

Pneumotaxic

8
Q

How do the respiratory groups in the medulla reach somatic innervation in the body, how does the body communicate back?

A
  • Reticular spinal tracts go to the cervical cord
  • Travel by the phrenic nerve to diaphragm and intercostal muscles
  • Afferents from alveoli through CN X go to the solitary nucleus, which triages input
9
Q

What type of reflex is respiration?

A

Visceral-somatic

10
Q

Describe the pathway of baroreceptor and chemoreceptor reflexes.

A
  • BP changes/ CO2 changes stimulating baro/chemoreceptor
  • Baroreceptors travel up CNs IX or X
  • Go to solitary nucleus
  • Decrease contractility of heart and blood vessels through the vagal nerve (CN X)
11
Q

What type of reflex is the baro/chemoreceptor reflex?

A

Visceral-visceral

Vagal-Vagal

12
Q

Describe the pathway of a cough reflex.

A
  • GVA info from the trachea, larynx, or pharynx travel to the nucleus solitarius via CN X
  • Solitary nucleus projects to upper respiratory centers to activate pneumotaxic center
  • Pneumotaxic center causes forced expiration (at diaphragm, intercostals, and abdominals)
  • Nucleus ambiguus contracts larynx and pharynx
13
Q

What initiates vomiting? Where is this structure found?

A
  • Area postrema

- Floor of 4th ventricle

14
Q

How does the area postrema cause vomiting?

A
  • Stimulation of AP triggers reflex
  • Signal projects to reticular formation
  • Travels down vagus nerve to contract contents of stomac (also relaxing gastroesophageal sphincter)
  • Travels down cord to abdominal muscles to contract
15
Q

What type of reflex is the vomit reflex?

A

Visceral-visceral and visceral-somatic

16
Q

What nerve do the afferents causing the vomiting reflex travel?

A

CN X

17
Q

What type of reflex is the pupillary reflex?

A

Somatic-visceral

18
Q

How is pupil dilation changed in the pupillary reflex of the medulla?

A

Touch/ pain receptors of skin in face

19
Q

What nerve supplies the afferent component of the papillary reflex? What structure do the afferents synapse on?

A
  • CN V

- Reticular formation

20
Q

Describe the efferent component of the pupillary reflex.

A
  • Descends down cord from RF
  • Stimulates betacell in lateral horn (Sympathetic)
  • Enters superior chain ganglion
  • Contracts muscle in eye
21
Q

What type of reflex is the carotid-sinus reflex?

A

Visceral-visceral

22
Q

What nerve carries the afferent fibers of the carotid-sinus reflex? What structure does it synapse on?

A
  • CN IX
  • Reticular formation
  • Dorsal motor nucleus of CN X
    AND
  • Nucleus ambiguus
23
Q

What nerve carries the fibers from the nucleus ambiguus and motor nucleus of CN X to the heart to reduce contractility in the carotid sinus reflex? Where does the nerve synpase?

A

CN X

  • On SA and AV nodes, and atrial muscle
24
Q

What nervous system is used to dilate blood vessels in the carotid-sinus reflex?

A

Sympathetic