Cutaneous Senses And Phys - 4/19 Karius Flashcards
What is the area from which stimulation produces activation of the neuron called?
Receptive field
What describes the relationship between perceived strength and actual measured intensity?
Eq?
Weber-Fechner Law
Perceived intensity = log(measured intensity)
K and A are constants which depend on what?
The type of sensory receptor
What is closer to the actual intensity compared to the perceived intensity: muscle or cutaneous senses?
Muscle
What pathway used for proprioceptive and discriminative (fine touch)
Dorsal column
What pathway used for thermal, nociceptive and coarse touch?
Spinothalamic
What does a pre-synaptic inhibition involve?
Post-synaptic cell is what?
End result or pre-synaptic transmission?
Axo-atonal synapse
Pre-synaptic terminal
Reduced nt release from the inhibited pre-synaptic terminal
Describe the pre-synaptic inhibition pathway involving neurons A, B, and C
- Neuron C releases GABA
- Cl- enters neuron A
- pre-synaptic terminal of A hyperpolarized and less Ca2+ may enter
- Less Ach release
- reducing probability of APs in neuron B
What does pre-synaptic inhibition allow the brain to do?
Increases the brain’s ability to localized the signal
Sensory information arrives at its respective column in what layer?
Via what?
Layer 4
Thalamus
Neighboring columns receive info from the the same what?
Different what?
Part of the body
Different sensory modality
Somatic Sensory Area 1 (S1) is located where anatomically?
Is what kind of stop?
Somatotopic representation of the toes and head?
Post-central gyrus
Brodmann’s 1, 2, 3
1st stop for most cutaneous senses
Toes medial
Head lateral
S2 is located where anatomically?
Receives input from where?
Wall of lateral (sylvian) fissure
S1
Fx of S1?
Integration of info for position sense, size, and shape discrimination
NOT COMPLETE INFO
Fx of S2?
Cognitive touch, stereognosis
Comparisons bw 2 different tactile sensations
Determining whether something becomes a memory
