somatosensory (touch) Flashcards
describe the difference between sensation and perception
sensation is taking in information from receptors, perception is how the pain is perceived
afferent information
taking in information from the environment, receptors to brain
efferent information
movement information, brain to muscles
what does the somatosensory system do
detect touch, temperature, pain, position in space, and movement
what organ is involved in somatosensory? what are the 3 parts?
skin. epidermis, dermis, hypodermis
epidermis
outermost layer of skin, constantly replaced by skin cells
dermis
middle layer, has mechanoreceptors and blood vessels
hypodermis
has blood vessels and adipose (fat) tissue
what are the different types of receptors in somatosensory
nocioception, hapsis, proprioception
what do somatosensory receptors tell the brain
when something occurs and if it is still occuring
noicioception
perception of pain
hapsis
perception of fine touch and pressure, helps to identify things we touch and grasp
proprioception
location and movement of body
what does the dorsal/posterior spinothalamic tract do
carries haptic and proprioceptive info (fine touch/location of body info) through the spine up the brain
what does the ventral/anterior spinothalamic tract do
carries nocioceptive (pain) info
describe the dorsal/posterior spinothalamic pathway
axons ascend spine ipsilaterally > form medial meniscus that goes up > synapse with ventral posterolateral nucleus of the thalamus > somatosensory and motor cortex
describe the ventral/anterior spinothalamic pathway
axons ascend spine contralaterally > form medial meniscus that goes up > synapse with ventral posterolateral nucleus of thalamus > somatosensory cortex
what is the function of the primary somatosensory cortex
takes projections from the thalamus in order to process sensory information
what is the function of the secondary somatorsensory cortex
refines construction of perception of info in order to confirm them before starting movements
what is the homunculus man
a man with differently proportioned body parts that correspond to the amount of sensory neurons in the part of the body. act as a visualization for density of neuron receptors (ie big hands for high density touch receptors)
why are pain receptors important
help to identify when something in the body is wrong
what is gate theory
a theory stating that when you hurt a body part (ie a stubbed toe) you can rub it to activate the haptic-prioceptive paths and deactivate pain path, which relieves pain.
what are the types of pain the body can receive
temperature and pressure
what are the different types of pain receptors
alpha delta: respond to quick pain since they are myelinated
C-fibers: unmyelinated and act slower to produce throbbing and aching
pain sensitive cells send information to the ___ cortex
somatosensory
what parts of the brain is pain relayed to
amygdala, hippocampus, prefrontal cortex
