Lecture 18: Viscerosensory Afferents Flashcards
What do visceral afferent neurons interface between?
visceral organs and the brain
What are the two visceral afferent pathways?
cranial visceral afferents and spinal visceral afferents
What is role of spinal visceral afferents?
send information to the brain about what is perceived in terms of the state of the internal organs
What is role of cranial visceral afferents?
send information to the brain about the function of the internal organs
Where are the cell bodies of spinal visceral afferents?
in the dorsal root ganglion
Approximately what percentage of inputs to the spinal cord are spinal viscerosensory afferents?
10%
Where do spinal visceral afferents terminate?
first terminate in the dorsal horn of the spinal cord
Where do spinal visceral ascending pathways lead to?
the thalamus, hypothalamus, pons/midbrain, rostral medulla and caudal medulla
What is the role of spinal visceral afferents?
visceral non-painful sensations, visceral discomfort and pain, referred pain, local organ feedback and shaping emotional state
What are all visceral organs innervated by?
either or both of the spinal and cranial visceral sensory neurons
What do spinal and visceral sensory neurons sense?
mechanical and chemical (and temperature) stimuli
Where do cranial visceral afferents first terminate?
in the solitary tract nucleus of the brainstem
What is the role of cranial visceral afferents?
visceral non-painful sensations, shaping emotional state relating to the body (interoception) and organ regulation, organ reflexes, neuroendocrine regulation
Where can the cell bodies for cranial visceral afferents be found?
nodose / inferior ganglion of the vagus
petrosal ganglion
jugular / superior ganglion of the vagus
What is the structure of a reflex?
sensor -> integration -> effector
