1.5 PHYSIOLOGY - Sensory Flashcards
Potential in triggering a sensory receptor
Generator Potential / Receptor Potential
Generator potentials trigger
Action potential trains
3 Characteristics of Sensory receptors. Define each.
- Differential Sensitivity - “specific sensations, specific receptors”
- Labeled Line Principle - “specific sensations, specific pathways”
- Adaptation - change in a way the receptor responds to sequential or prolonged stimulation
2 Types of adaptation
- Slowly adapting receptors
2. Rapidly adapting receptors
Slowly adapting receptors
TONIC receptor
continuous stimulus strength (detects steady stimulus)
Examples of slowly adapting receptors
Muscle spindle, Golgi Tendon, Slow pain, Baroreceptor, Chemoreceptor
Rapidly adapting receptors
PHASIC receptor ("Mabilis magsawa")
for detecting change in stimulus strength
detects onset and offset of stimulus
Predictive functionExamples of rapidly adapting receptors
Pacinian corpuscle
Region of the skin where stimuli can change the firing rate of the sensory neurons
Receptive Field
2 types of Receptive Field
Type 1 - smaller RF with well-defined border
Type 2 - wider RF with poorly-defined border
Non-hairy skin
Glabrous skin
Iggo Dome receptors
Merkel’s Disc
Onion-like structure
Pacinian Corpuscles
Sensory encoded of free nerve endings
Touch and temperature
tactile receptor in glabrous skin (esp fingertips and lips)
Meissner’s corpuscles
Tactile receptor for continuous touch, localizing touch sensation and determine texture
Merkel’s disc
Detects high frequency vibration
Pacinian Corpuscles
Receptor located in deep skin, internal tissues, and joint capsules. Multi-branched, encapsulated, and slowly-adapting
Ruffini’s end organs
Encodes movement of objects and low frequency vibrations
Meissner’s corpuscle
Identify the type of receptor and receptive field.
Meissner’s Corpuscle
FA1
Identify the type of receptor and receptive field.
Merkel’s Disc
SA1
Identify the type of receptor and receptive field.
Ruffini’s end organs
SA2
Identify the type of receptor and receptive field.
Pacinian Corpuscles
FA2
Identify the first-4th order neuron in the sensory pathways
Sensory receptors 1st order: Cell body: dorsal Root or Cranial Nerve Ganglia 2nd order: spinal cord or brainstem 3rd: thalamus 4th: sensory cortex
