Reticular Formatio & Cerebellum Flashcards
(54 cards)
What does the reticular formation regulate?
posture some stereotypic motor functions the internal environment pain regulation sleep & wakefulness emotional tone
Where is the lateral zone most prominent?
rostral medulla & caudal pons
T/F: Reticular formation influences spinal motor neurons directly.
True
Describe the theories behind bruxism.
Peripheral cause: malocclusion results in premature and one-sided contact; based on clinical observation
Central cause: sleep-related dysfunctions cause bruxism; input to supratrigeminal nucleus may be from basal ganglia, lateral hypothalamus, and central nucleus of the amygdala
Select the incorrect pair:
A. Raphe: adjacent to sagittal plane
B: Medial Zone: source of most ascending projections
C: Lateral Zone: cranial nerve reflexes
D: Lateral Zone: visceral functions
E: Medial Zone: source of most descending projections
F: Lateral Zone: prominent in midbrain
Answer: F. Lateral Zone: prominent in midbrain.
The lateral zone is prominent in the caudal pons and rostral medulla
Select the true statement concerning reticular formation:
A. Phylogenetically ancient
B. Forms central core of brainstem
C. Extent not truly appreciated in routine brainstem sections
D. Extends into cerebrum as the hypothalamus
E. All the above are true
Answer: E. All the above are true
What characteristics of reticular formation are termed the “medulla vital center?”
heart rate
respiration
swallowing, vomiting
What specific region is responsible for pain regulation
PAG: periaqueductal grey
Bilateral damage to the RF in what area of the brainstem would result in prolonged coma?
midbrain
ARAS - ascending reticular activating system (role in sleep-wakefulness cycle)
What are the neurochemical signatures of the following structures:
Brainstem
Hypothalamus
Telenchephalon
Brainstem: norepinephrine (locus ceruleus), dopamine (substantia nigra), serotonin (raphe)
Hypothalamus: histamine
Telencephalon: acetylcholine
What is the major function of the locus ceruleus?
attentiveness (arousal)
When norepinephrine is released in the cortex from the locus ceruleus, what is the result?
facilitates attention to selected stimuli
When norepinephrine (NE) is released in the trigeminal spinal nucleus and spinal cord, what is the result?
suppresses incoming pain signals
Why is a balance of NE important?
too little: depression
too much: panic disorder
Describe RF’s role in pain sensation.
PAG receives pain info from SPINOMESENCEPHALIC fibers
PAG also gets input from hypothalamus, cortex, etc. (may contain behavioral info; “should pain suppression be activated?”)
PAG to raphe then to posterior horn of spinal cord/spinal V nucleus
What nuclei use NE as their neurotransmitter?
Medulla: solitary nucleus (memory)
Rostral Pons: locus ceruleus (attention)
ventrolateral medulla (pain regulation)
What nuclei use dopamine as their neurotransmitter?
In the midbrain:
- Substantia nigra (putamen & caudate)
- Ventral tegmental area (limbic system)
What are the tracts found in the ventral tegmental area? What do those tracts do?
Mesolimbic tract (goes to limbic system): nucleus accumbens septi - sense of reward or well being Mesocortical tract (goes to frontal cortex): organizes and initiates behavior
What neurological disease is associated with the ventral tegmental area?
Schizophrenia
- disorganized thinking (frontal area)
- hallucinations (limbic system/temporal lobe)
What is the function of the nucleus accumbens septi?
sense of reward or well being
When does a schizophrenic patient tend to exhibit social withdraw? When would a patient exhibit hallucinations?
social withdraw: low dopamine
hallucinations: high dopamine
What do raphe nuclei use as a neurotransmitter?
serotonin
What is the role of the raphe magnus? What neurotransmitter does it use?
pain suppression
It is a part of the medullary raphe nuclei - serotonin
Where are descending NE fibers going to?
trigeminal spinal nucleus
spinal cord
