General Sensory Systems Flashcards
Dull pain & warmth are detected by which type of nerves?
A. A fibers
B. C fibers
C. Ia fibers
D. Ib fibers
B. C fibers
Which touch receptors have are large receptive field and have fast adaptation responses?
Pacinian corpuscles
Which part of body has the best 2 point discrimination ability?
Fingers
Which proprioceptive organ is sensitive to muscle stretch/lengthening, maintains muscle tone, and has Alpha motor neurons, Gamma motor neurons, Ia afferent fibers and II afferent fibers?
Muscle spindles
Which propriceptive organ has free nerve endings at muscle junctions, detect so pulling forces at junction, and projects type Ib afferent fibers?
Golgi tendon organ
Which propriceptive organ has free nerve ending w/in joint capsule, is insensitive to limb position in normal range, and detects limb position at extremes and inappropriate directions?
Joint receptors
Explain the range of heat receptors
Response is linear within range and then drops off
No response above heat pain threshold
Explain range of cold receptors
Response is strong to cold and decreases as stimuli become warmer
Paradoxical cold - at very high temp cold receptors increase response
What type of fibers are thermal/mechanical nociceptors? These fibers have small diameter, thinly myelinated, and conduct fairly slowly at about 5-10m/s.
A. C fibers
B. Ib fibers
C. II fibers
D. A-delta
A-delta
What type of fibers are polymodal nociceptors? These fibers have small diameter, unmyelinated, and conduct slowly at about 0.5-2m/s.
A. C fibers
B. Ib fibers
C. II fibers
D. A-delta
A. C fibers
Which mechanism explains why rubbing the area around your injury make it feel better. Non-pain activity inhibits the nociceptive pathway?
Gate theory
What is the function of endogenous opiates in modulation of pain?
A. Increase calcium intake into post synaptic neuron
B. Increase neurotransmitter release
C. Prevent calcium influx into post synaptic neuron
D. Prevent calcium influx into pre-synaptic neuron
D.
Endogenous opiates —> prevent Ca2+ influx into pre synaptic neuron –> decreases neurotransmitter release —> reduces post synaptic depolarization
Sensory pathway responsible for conscious proprioception and discriminative touch
DCML
Sensory pathway responsible for Pain, temp, and light pressure
Spinothalamic tract
Most medial part of sensory cortex receives sensory info from what part of the body?
Feet
