lecture 11 Flashcards
(53 cards)
describe afference of the PNS
- cutaneous receptor, free nerve ending, abdominal viscera, etc. receives sensory information from stimuli
- information is passed back to sc via rami, then spinal nerve, then dorsal root to the dorsal horn
describe efference of the PNS
- information from the spinal cord (ventral horn) is passed to body via the ventral root, spinal nerve, then rami
- usually innervate skeletal muscle
what is the difference btwn rami and root?
- dorsal/ventral root only carry afferent/efferent information, rami do both (more information flow)
- rami are larger
cutaneous receptors are the _____ response to _____?
primary afferent response to mechanical stretch
with cutaneous receptors, mechanical stretch energy is converted into ________ so it can be sent as a signal to the brain
electrical energy
describe how the conversion of mechanical stretch to electrical energy works
stretch allows Na to flow into the cell, converting mechanical energy to a chemical signal
what are the 4 sensory receptors attributes
- intensity
- modality
- duration
- location
describe intensity as a receptor attribute
discharge of receptor increased with stimuli
describe modality as a receptor attribute
percept is constant for a given receptor
doesn’t matter how the receptor is stimulated, it always sends the same signal to the brain - e.g. sound, vision
describe duration as a receptor attribute
receptors may be slowly adapting (one large signal then consistent little signals) or rapidly adapting (one large signal)
describe location as a receptor attribute
perception is confined to the receptor’s location
what are the two types of cutaneous receptors?
nonencapsulated and encapsulated
what are the subtypes of nonecapsulated cutaneous receptors?
free nerve endings, hair follicle receptors, markel’s discs
where are free nerve endings, what is their modality, and what is their adaptation (duration)?
- glaborous and nonglaborous skin (dermis)
- pain, temperature, touch, pressure
- varies
where are hair follicle receptors, what is their modality, and what is their adaptation (duration)?
- nonglaborous skin (dermis)
- touch
- rapid
where are Merkel’s discs, what is their modality, and what is their adaptation (duration)?
- glaborous and nonglaborous skin (dermis)
- touch
- slow
what are the subtypes of encapsulated cutaneous receptors?
- Meissener’s Corpuscle
- Pacinian Corpuscle
- Ruffini Ending
where are Meissener’s Corpuscles, what is their modality, and what is their adaptation (duration)?
- glaborous skin (dermis)
- touch
- rapid
where are Pacinian Corpuscles, what is their modality, and what is their adaptation (duration)?
- glaborous and nonglaborous skin (hypodermis)
- pressure/vibration
- very rapid (imp for vibration)
where are Ruffini Endings, what is their modality, and what is their adaptation (duration)?
- glaborous and nonglaborous skin (hypodermis)
- stretch
- slow
describe the receptive feild of Meissener’s Corpuscles (rapidly adapting)
small (only exists at point of contact)
describe the receptive feild of Pacinian Corpuscles (rapidly adapting)
larger area than Meissener’s, but most sensitive at point of contact
describe the receptive feild of Ruffini Endings (slowly adapting)
generally larger area than Merkel’s, but are similar in orientation to that of the corpuscle
describe the receptive feild of Merkel’s discs (slowly adapting)
smaller than Ruffini endings (only rlly exists at point of contact)
