Somatic Sensation Flashcards
For a free nerve ending:
What is the Primary Sensory
What is the Secondary Sensory
What does the Synapse have…
And what is its adaptation?
For Meissner’s Corpuscles:
What is the Primary Sensory
What is the Secondary Sensory
What does the Synapse have…
And what is its adaptation?
For Pacinian Corpuscles:
What is the Primary Sensory
What is the Secondary Sensory
What does the Synapse have…
And what is its adaptation?
For Ruffini Corpuscle:
What is the Primary Sensory
What is the Secondary Sensory
What does the Synapse have…
And what is its adaptation?
For Merkel receptors:
What is the Primary Sensory
What is the Secondary Sensory
What does the Synapse have…
And what is its adaptation?
What do all these skin sensory receptors feel for?
Define noxious stimuli.
Stimulus, which is left in contact with the tissue will cause damage.
What’s the speed of light vs speed of conduction of neurons for us?
Light: 3x10^8
Conduction(us): 1x10^2. Waaaay slower :(.
When are cold receptors activated?
When the temperature is lower than body temperature.
There are two types of warm receptors, what are the conditions for each to activate?
- Literal warm receptors: Above body temperature to about 45°C. (113°F)
- Pain receptors activated above 45°C.(113°F)
What type of channel do all thermoreceptors use?
Cation channels called transient receptor potential channels. Or TRP Channels.
For (Somatosensory) Alpha-beta Nerve fibers:
What are the Fiber Characteristics.
What is the speed of conduction.
What stimuli is it associated with?
They are Large, and Myelinated
30-70 m/sec
Mechanical Stimuli
For (Somatosensory) Alpha-delta Nerve fibers:
What are the Fiber Characteristics.
What is the speed of conduction.
What stimuli is it associated with?
Small, myelinated
12-30 m/sec
Cold, fast pain, mechanical stimuli.
For (Somatosensory) C Nerve fibers:
What are the Fiber Characteristics.
What is the speed of conduction.
What stimuli is it associated with?
Small, unmyelinated
0.5-2 m/sec
Slow pain, heat, cold, mechanical stimuli
For (Somatosensory) Alpha-alpha Nerve fibers:
What are the Fiber Characteristics.
What is the speed of conduction.
What stimuli is it associated with?
Large, myelinated
80-120 m/sec
Proprioception: sense of self/sense of position of limbs.
Explain what sensory neurons dictate how precise we can feel the sense.
It is based on how many primary sensory neurons go to a singular secondary sensory neuron.
The more primary sensory neurons that go to a singular secondary sensory neuron the less specific the receptive field is and vice versa .
Primary neuron response is _________ to stimulus strength.
Proportional
When the primary neuron stimulates the secondary neuron, the secondary neuron then inhibits surrounding neighboring secondary neurons, why?
The inhibition of lateral neurons, enhances perception of the stimulus to give a more precise location of original stimulus.
What are the four types of somatic sensation?
Touch, proprioception, temperature, nociception(pain and itch).
Where do the pathways for somatic perception project to in the brain?
To the cortex and cerebellum.
Where are the receptors located for somatic senses?
Skin and viscera.
Where do primary sensory neurons synapse? (Connect to other neuron, which one and where?)
Synapse in CNS with secondary sensory neurons.
Where do secondary sensory neurons synapse? (Connect to other neuron, which one and where?)
Interneruons in the CNS - synapse with tertiary sensory neurons in the thalamus
Where do tertiary sensory neurons synapse? (Connect to other neuron, which one and where?)
Project to Somatosensory cortex and many project to the cerebellum Somatosensory cortex.