Somatosensory System Flashcards
organization ofareas within the CNS (SC and Brain)
somatotopic
Peripheral Sensory neurons have 2 axons:
________ axons conduct messages from receptor to cell body
________axons project from cell body into spinal cord or brainstem
distal
proximal
somatosensory peripheral neurons do what?
pain pressure temperature touch etc
main difference between motor and sensory neuron?
cell body
which axons transmit faster and why
larger diameter because they are myelinated so their resistance to current flow is less
types of axons
large (myelinated- fastest)
medium
small
unmyelinated (slowest)
which axon does proprioception of skeletal muscle
largest
axon: mechanoreceptors of skin
medium
axon: paint, temperature
small
axon: temperature, pain, itch
unmyelinated
Area of skin innervated by single afferent neuron
receptive field
which part on your body would have smaller and greater density receptive field
fingers
which part of your body would have larger and less dense receptive field
back
3 types of skin sensation
touch
pain
temperature
2 point discrimination tool: how does this work on your fingers and back?
on your fingers you can feel both pins but on your back you can only feel one
In general, the type of environmental energy that a specific receptor responds to is
unique and unimodal
classify receptors by (4)
structure
source
type
rate
Free and diffuse nerve endings
Encapsulated receptors
structure classification
Exteroreceptors– Interoreceptors
– Proprioceptors
classifying by source of stimulus
Slowly adapting
– Rapidly adapting
classifying somatic receptors by rate of adaption
Primary source of information to Spinal Cord
somatic receptors
somatic receptors determine what?
activity and output of the CNS
5 types of receptors
chemo photo thermo mechano noci
Smell, taste, pH, metabolites
chemoreceptors
