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exteroreceptor
Recieve sensory information from outside of the body. Examples: Visual, auditory, tactile, gustatory, and olfactory TERM 2
visceroreceptor
DEFINITION 2 sensory receptors that produce sensations from organs or internal tissues. - Sensations include pain, hunger, thirst, fatigue or nausea. -Visceroreceptorslocated within the circulatory system are sensitive to blood pressure changes are called barroreceptors. TERM 3
proprioreceptors
DEFINITION 3 Unconscious information recieved. Detect body position in space and movement. Located in the muscles, tendons, and joints inside the body and semicircular canals of the inner ear TERM 4
phasic
DEFINITION 4 size of generator potential can diminish TERM 5
phasic receptors
DEFINITION 5 for tonic receptors, the sensory neuron fires action potential as long as the receptor potential is above threshold. phasic receptors respond to change in stimulus intensity but adapt if the strength of the stimulus remains constant.
tonic
if size of generator potential increases (and is over threshold), frequency of AP is increased TERM 7
sensory receptor adaptation
DEFINITION 7 page 334. TERM 8
sensory receptor
DEFINITION 8 the molecular mechanism for sensory receptor adaptation depends on the receptor type. in some receptors K+ channels in the receptor membrane open, causing the membrane to repolarize and stopping the signal. in other receptor Na+ channels quickly inactivate.Specialized nerve cell that is designed to respond to a specific sensory stimulus TERM 9
3 types of sensory
receptors
DEFINITION 9
- Exteroceptors 2.Interoceptors 3.Proprioceptors TERM 10
What are the 5 special sense
receptors?
DEFINITION 10
- Visual 2.Olfactory 3.Auditory 4.Gustatory 5.Equilibrium
thermoreceptors
TemperatureHeat and cold: different neurons (mostly cold) TERM 17
Mechanoreceptors
DEFINITION 17 Deformation of the cell membrane. Light touch, pressure, Hair cells TERM 18
Nociceptors
DEFINITION 18 Pain and Higher threshold.Free nerve endings C fibers and some A-delta fibers TERM 19
generator receptor potential
DEFINITION 19 local depolarization of the membrane potential at the end of a sensory neuron in graded response to the strength of a stimulus applied to the associated receptor organ, a pacinian corpuscle; if the generator potential becomes large enough (because the stimulus is at least of threshold strength) TERM 20
transduction
DEFINITION 20 Transduction: the conversion of stimulus energy into a membrane potential (receptor potential, generator potential); the mechanism by which the body changes energy from one modality to another
EPSP
Then there is aflowof positively charged ions towards the postsynaptic cell, a momentary depolarization of the postsynaptic membrane potential occurs. This phenomenon is known as EPSP. A postsynaptic potential becomes excitatory when the neuron is triggered to release an action potential TERM 22
AP
DEFINITION 22 Action potential is fired by EPSP. When there is a signal, the neurons communicate with each other reaching EPSP until it needs to fire an action potential. Voltage-gated ion channels produce action potentials. These channels lie inside theplasmamembrane of the cell. TERM 23
specific nerve energy
DEFINITION 23 eachsensoryreceptororgananditsnervefiberreceiveandtransmitjus TERM 24
does each nerve respond to only one
stimulus?
DEFINITION 24 Each sensory neuron carries information about only one sensation: they usually respond best to one form of stimulus energy (but other stimuli can evoke a response).It ISNT THE NEURON, its WHERE IT GOES IN THE CNS TERM 25
Normal or Adequate stimulus
DEFINITION 25 Allows receptors to function as filters Requires the least amount of energy to start an AP Under normal conditions (no tissue injury) correct CNS interpretation of receptors
go over examples of receptors from
slides
powerpoint TERM 32
punctate distribution
DEFINITION 32 the pattern of uneven distribution of sense receptors throughout the body. in some areas receptors are sparse and others densely clustered TERM 33
absolute value
DEFINITION 33 when thermoreceptors detect temperature based on actual value. water feels room temp regardless of whether hands are cold or hot TERM 34
receptive field?
DEFINITION 34 the cutaneous area in which stimulation will result in changes in the firing rate of a receptor TERM 35
receptive field; lateral inhibition
DEFINITION 35 The sensory neurons that are most strongly stimulated will inhibit the sensory neurons whose fields are less stimulated.An object that is larger than an individual receptive field and stimulates several receptors will cause lateral inhibitionex: lateral inhibition within central nervous system. blunt object touching skin.
why does receptive fields vary and how are
they measured?
Varies inversely with the density of receptors in a region.Measured by the twopoint touch threshold test: tactile acuity TERM 37
tactile receptor field?
DEFINITION 37 Tactile receptor field corresponds to area in CNS somatosensory cortex.Accuracy of 2 point discrimination depends on distribution of receptors
