Brainstem Functions Flashcards
3 basic functions of the brainstem:
- Conduit
- CN functions
- Integrative
What functions does the brainstem integrate and regulate?
some motor respiratory cardiovascular consciousness pain modulation
Within the reticular formation, there is a great deal of _____: a single cell responding to several sensory inputs.
convergence
large dendritic fields
Within the reticular formation, there is a great deal of _____: a single cell projecting to several different targets through collaterals.
divergence
What are the 3 zones of the reticular formation?
- Raphe
- Medial zone
- Lateral zone
The ____ is a group of cells on either side of the reticular formation midline.
raphe
The ____ zone contains large and small neurons with long axons, comprising most of the long ascending and descending projections out of the RF.
medial zone
The lateral zone of the RF is particularly prominent in which levels?
rostral medulla and caudal pons
The ____ zone of the RF is primarily involved with CN reflexes and visceral function.
lateral
The ___ zone of the RF is considered the receiving zone.
lateral
Which motor tracts participate in postural control and walking as part of the reticular formation?
Medial and Lateral Reticulospinal tracts
Medial and Lateral Vestibulospinal tracts
What are three sensory functions of the reticular formation?
- modulates reflex response to noxious stimulus
- certain areas of the RF also play a major role in the modulation on nociception
- sensory integration related to postural control
The periaqueductal and periventricular gray substance are involved in ____ control and contain high levels of ____.
pain control
endorphins
Respiratory centers are located in what area of the RF?
medullary and pontine RF
Respiratory centers receive input from _____.
chemoreceptors
re: pH, blood oxygen levels, stretch receptors
Lesions of the respiratory centers produce distinct abnormal breathing patterns because:
influence over phrenic nucleus C3-5
rhythmical patterns and pacemaker (ie: CPG for breathing)
Cardiovascular control centers are located in what area of the RF?
medulla
Cardiovascular control centers receive input from _____.
baroreceptors
inputs from CN IX and X
Cardiovascular control centers project to ____.
autonomic nuclei of the SC
BP control centers are located in ____.
ventrolateral medulla
Cardiovascular control centers have reciprocal connections with the ____ system.
Evidence?
limbic system
evidence: panic attacks and limbic responses (ie: anger) expressed via autonomic centers in medulla
What visceral control center is associated with coughing, hiccuping, sneezing, yarning, shivering, gagging, swallowing, laughing, and crying?
Cardiovascular control centers
T or F:
Damage to visceral control centers is life threatening.
True
The hypothalamus projects to area of the brainstem that influence the ____ system.
sympathetic
Describe the course of hypothalamic projections to the brainstem:
some descending projections synapse in RF
some proceed directly to SC
Damage to hypothalamic projections can cause ____ syndrome.
horners
Loose sympathetic innervation to 1/2 of the face (miosis, ptosis, enophthalmus, flushing, anhydrosis of ipsilateral face)
Describe the course of fibers that are responsible for normal state of consciousness:
portion of midbrain and rostral pontine RF project to intralaminar nuclei of thalamus which projects to all areas of cortex
The control of consciousness is known as the:
ARAS: ascending reticular activating system
Interruption of the ARAS pathway results in:
coma (disruption of arousal)
respiratory and cardiovascular disturbances
ARAS pathway works along with axons from ____ in modulating activity of the cerebral cortex.
locus ceruleus
In addition to control of consciousness, parts of the RF also play an important role in:
sleep
What are the 3 neurochemically distinct systems of the brainstem?
NE
Dopamine
Seratonin
Locus ceruleus contains _____ causing it to appear black in unstained sections.
neuromelanin
Locus ceruleus works with ____ to modulate activity in cortex for attention.
ARAS
Locus ceruleus has downstream projections to the ____ to facilitate motor recruitment.
SC
Where is locus ceruleus located?
near the PAG in the midbrain and rostral pons
NE is associated with _____ to control attention, sleep-wake, and mood.
locus ceruleus
Dopamine is associated with ____.
substantia nigra and ventral tegmental area
Seratonin is associated with ___.
raphe nuclei
Raphe nuclei projections to the SC are involved in ____.
pain modulation
Raphe nuclei project to systems involved in:
depression, anxiety, OCD, aggression, eating disorders
Substantia nigra is part of the ____ system.
mesostriatal
Substantia nigra pojects to the _____.
basal ganglia
Depletion of Substantia nigra cells results in ____ disease.
parkinson’s
The Ventral tegmental area is located:
medial to substantia nigra
The Ventral tegmental area projects to:
mesocortical and other limbic areas
The Ventral tegmental area is involved in:
MESOLIMBIC: addiction, reward, pleasure
MESOCORTICAL: attention, motivation, schizophrenia
