Exploring something with your hands trying to figure out what it is (tectile exploration)
caused by an external event, with energy applied
awareness of a stimulus
awareness of a stimulus + internal construct of the sensory experience
mechano, chemo, thermo, nocio
what are some of the classifications of receptors?
where are exteroreceptors found?
where are proprioceptors found?
What are receptors found in viscera called?
a non neural structure surrounding the end of the fiber
What makes a receptor encapsulated?
rapidly adapting and slowly adapting
What are the different rates of adaptation?
What type of information is processed in the lateral area of the posterior root entry zone?
What type of info is processed in the medial area of the posterior root entry zone?
rapidly adapting (phasic)
what type of receptors respond to sudden changes in stimulus energy and have a rapid decrease in action potentials frequency with constant stimulus?
slowly adapting (tonic)
what type of receptors continue to respond to continuous stimulus, and may have a slight increase or decrease in AP over time?
altered channel sensitivity to prolonged stimulus, or filtering by non neural tissues
What are some possible mechanisms for rapid adaptation?
receptor density, receptor field size, or central processing
What may affect the ability to localize a stimulus?
Free nerve endings
What type of receptors are terminations of C and A(d) fibers, unencapsulated, slowly adapting and found in most tissues/organs?
what type of receptors respond to stimuli that can damage tissue?
constantly active sending information
are thermoreceptors and mechanoreceptors tonicly active?
what type of receptors process descriminitive tactile sensations?
What type of fibers innervate cutaneous mechanoreceptors?
What type of cutaneous mechanoreceptor deals with form and texture perception (points, edges, curves)?
Where is the highest density of Merkel endings found?
What type of cutaneous mechanoreceptors deal with the detection of course form, flutter or motion across the skin such as an object slipping/grip?
are merkel endings slowly or rapidly adapting?
are meissner corpuscles slowly or rapidly adapting?
small receptive fields
Why are merkel endings and meissner corpuscles so highly descrimitive?
Which type of cutaneous mechanoreceptors detect joint position and direction of object motion if there is skin stretch?
are Ruffini endings slowly or rapidly adapting?
deep in skin
Where are Ruffini endings found?
What type of cutaneous mechanoreceptors help detect texture, particularly through a tool?
are pacinian corpuscles slowly or rapidly adapting?
deep in skin
Where are Pacinian corpuscles found?
describe the receptive field for pacinian corpuscles
describe the receptive field for Ruffini endings
hair follicle receptors
What type of receptors are commonly used to detect light touch and non-descriminitive touch?
Frequency of AP and number of receptors activated
What may help determine stimulus intensity?
descrimination between two closely placed stimuli
does descriminitive touch have low or high resolution?
receptor density and size of receptor fields
What affects resolution?
More convergence leads to ________ descrimination
periphery to CNS
Where does a first order neuron go?
tract cell to thalamus
Where does a second order neuron go?
thalamus to cortex
Where does a third order neuron go?
periphery to cerebellum
Where does a 2 neuron pathway travel from and to?
Greater convergence leads to __________ resolution.
inhibition and facilitation
What helps enhance signal to noise ratio, and filter out background noise?
does the ALS have low or high resolution?
do the posterior columns have low or high resolution?
cutaneous mechanoreceptors, temperature, some pain
What type of info do areas 3b and 1 of the primary sensory cortex receive?
cutaneous and deep receptors, including proprioceptors
What type of receptors send info to area 3a and 2 of the primary sensory cortex?
VPL and VPM
What are the major thalamic afferents to the primary sensory area?
What might a lesion to the primary sensory cortex result in?
inability to decide what an object is by feel
process pain info, and memory of sensory info
What are the primary functions of the secondary sensory cortex?
VPI, VM, PO, VPL, VPM
The secondary sensory cortex receives info from what thalamic nuclei?
integration of sensory info
What is the primary sensory function of the posterior parietal association cortex?
non dominant hemisphere
lesions to the posterior parietal association cortex are most pronounced when the lesion is where?
no motor deficits, but lack of ability to put motor patterns together
what nerve is primarily responsible for sensory info from the face/cranium?
facial, glossopharyngeal, vagus
What other 3 nerves contribute sensory info from the face?
spinal trigeminal, principal sensory, mesencephalic
What three nuclei are associated with the trigeminal nerve?
Which portion of the spinal trigeminal nucleus deals with pain and temp info?
which section of the spinal trigeminal nucleus deals with pain info from the oral cavity?
tactile sensations (descriminitive)
what type of info does the principal sensory nucleus receive?
what type of info does the mesencephalic nucleus receive?
does the anterior trigeminothalamic tract have crossed or uncrossed projection?
does the posterior trigeminothalamc tract have crossed or uncrossed projections?
anterior and posterior spinocerebellar tracts
What tracts are the primary pathways for lower extremity unconcious proprioception?
nucleus of clarke
Where does the posterior spinocerebellar tract originate in the spinal cord?
which spinocerebellar tract crosses twice?
What is the primary pathway for upper extremity unconcious proprioception info?
accessory cuneate nucleus
Where does the cuneocerebellar pathway originate in the caudal medulla?