Reticular Formation Flashcards
What does the reticular formation control?
sleep and wakefulness, motor system modification, vomiting, and swallowing
What parts of the brain does the reticular foramation go through?
midbrain, pons, and medulla oblongata
What do reticular neurons monitor?
ascending and descending traccts
Each neuron in the reticular formation has ____ collateral neurons.
many
What is the ARAS?
the ascending reticular activating system
What structures are involved in the ARAS?
reticular formation, thalamus and cortex
In order for the reticular formation to influence the cortex, what structure must it communicate to first?
the thalamus
What part of the reticular formation is involved in the ARAS?
the rostral reticular formation
How does the ARAS function in arousal?
it ‘wakes up’ the cortex by way of the thalamus so that it can perceive input
How does the ARAS function in consciousness?
the ARAS acts to keep the cortex awake by constantly stimulating the thalamus
While asleep does the activity of the ARAS increase or decrease?
decrease
While asleep does the activity of the thalamus increase or decrease?
DECREASE
What part of the reticular formation is involved with sleep?
pontine reticular formation
If the pontine reticular formation is lesioned, what happens to your sleep habits?
you will not be able to fall asleep
What is the target of anesthesia?
thalamic neurons
What are the two reticulospinal tracts?
pontine and medullary
What side of the body does the pontine reticulospinal tract affect?
ipsilateral
What is the function of the pontine reticulospinal tract?
it excites extensors and inhibits flexors
Where does the pontine reticulospinal tract run?
in the ventral funiculus
What side of the body does the medullary reticulospinal tract effect?
ipsilateral
What is the function of the medullary reticulospinal tract?
excites flexors and inhibits extensors
Where does the medullary reticulospinal tract run?
in the lateral funiculus
A lesion in the pontine reticulo spinal tract would result in an (a) increase or (b) decrease of excitation of antigravity muscles on the (a) same or (b) opposite side of the body.
(b) decrease, (a) same
What is a central pattern generator?
a dedicated circuit of neurons that act to produce a specific sequence of events
What nerves are essential for swallowing?
IX, X, and XI
In the swallowing reflex, what does the swallowing center get information from?
the nucleus of the solitary tract
In the swallowing reflex, what nucleus sends motor output to IX, X, and XI?
nucleus ambiguous
Where is the swallowing center located?
in the medullary reticular formation
Where is the vomiting pattern generator located?
in the medullary reticular formation
Where does the vomiting center receive inputs from?
the chemical trigger zone, vestibular system, stomach and small intestine, and cortex
What is the final stop in the vomiting pattern generator?
the vomiting center
Where is the chemical trigger zone located?
area postrema
What is special about the blood-brain barrier at the chemical trigger zone?
it is incomplete
