Question | Answer |
What are the 3 zones of the RF? | Midline, Medial, Lateral |
Describe the midline zone. | called the "raphe"; neurotransmitter is serotonin |
Describe the medial zone. | outputs of the RF; large neurons |
Describe the lateral zone. | projects axons to the medial zone; small cells |
What is the normal neurotransmitter in the RF neuron? | ACh |
What are the 3 general functions of the RF? | Motor fxn, Visceral fxn, Consciousness |
Where is the origin of the reticulospinal tract? | medial zone of RF; pons and medulla |
What is the course of the reticulospinal tract? | ventral and lateral funiculi of spinal cord |
What is the termination of the reticulospinal tract? | mostly ipsilateral; medial ventral horn and intermediate gray |
What are 2 fxns of the reticulospinal tract? | maintain posture; produce gross body movements |
What kind of signals are in visceral center projections to the spinal cord? | preganglionic symp and parasymp |
What kind of signals are sent to the brainstem from the visceral centers? | GVE and SVE nuclei of cranial nerves |
What is the most important clinical function of the RF? | regulation of sonsciousness |
What is the ARAS? | ascending reticular activating system |
What is the origin of the reticulothalamic tract? | medial zone of the RF |
What is the course of the reticulothalamic tract? | central tegmental tract CTT |
What is the termination of the reticulothalamic tract? | intralaminar nuclei of the thalamus |
What tract gives widespread activation of the cortex? | thalamocortical projections |
What activates ARAS? | somatosensory from lateral spinothalamic tract; visual, auditory, visceral |
What are some causes of lesions in the RF? | vascular lesions/tumors in brain stem; uncal herniation; tonsilar herniation |
What are some signs of lesions to the RF? | disturbances of consciousness; changes in mm tone and postural reflexes; visceral dysfunction to cardio/respiratory |
What are the 3 monoaminergic systems found in the RF? | serotonin, NE, Dopamine |
What are the ascending and descending fxns of the serotonergic pathway? | desc: pain inhibition; asc; sleep and mood |
Where does the serotonergic pathway originate? | midline raphe |
Where do the serotonergic neurons project to? | cerebral hemisphere (sleep/mood); spinal cord (analgesia) |
What are the fxns of the ascending NorEpi pathways? | mood, attention, memory |
Where does the NorEpi pathway originate from? | locus ceruleus in upper pons |
Where do the dopaminergic neurons originate? | substantia nigra and ventral tegmental area |
Where does the substantia nigra project to? | caudate and putamen |
Where does the ventral tegmental area project to? | forebrain areas; amygdala, prefrontal cortex, nucleus accumbens |
Excess dopamine release in prefrontal cortex and amygdala is associated with what disorder? | schizophrenia |
What are the two pathways and associated fxns with the dopaminergic pathways | nigrostriatal: motor; mesolimbic: behavior and emotion |