CH 19 Pt2 Cd

Question 1

Vestibular sense

Answer 1

Where the body is in space
-integrates with the visual system to enhance a sense of equilibrium and balance

Question 2

Proprioceptive Sense

Answer 2

Where the body is relative to other parts of the body
-receptors in the muscle, joints, tendons

Question 3

Proprioceptors

Answer 3

Relay information about muscular dynamics and limb movement (kinesthetic awareness)
-relay info about muscle dynamics and limb movements to conscious and subconscious areas within the CNS
MONITOR MOVEMENT AND ALLOW FOR MODIFICATION

Question 4

Specialized sensory receptors sensitive to stretch, tension, and pressure? (2)

Answer 4

Muscle Spindles
Golgi Tendon Organ

Question 5

Muscle Spindles

Answer 5

Receptor (intrafusal fibers) in the muscle that is aligned to parallel to muscle fiber (extrafusul fibers)
-detects stretch in the muscle (fiber length and tension)
-responsive to rate and amount of stretch

Question 6

Stretch Reflex with Muscle Spindles

Answer 6

MS responds to stretch, sends excitatory input to motor neuron in spinal cord
-intimates an equal or stronger action to reduce this stretch
-can cause muscle contraction
Inhibitory input is sent to antagonist muscle to counteract

Question 7

Proprioceptors use the Reflex Arc

Answer 7

Activation of MS relays Afferent impulses through spinal cord
Spinal cord sends efferent impulse to cause reflexive activation of motor neurons of stretch muscle
-causes muscle to act more forcefully and shorten -reduces stretch stimulus from spindles

Question 8

What creates more contraction, counter movement or no counter movement

Answer 8

Counter movement. Muscles will want to rapid stretch causing a muscle reflex to launch/ go back to normal faster

Question 9

GTOs

Answer 9

Golgi Tendon Organs
-receptors found at the junction between tendons and muscle fibers
-lie parallel to muscle fiber
-detects stretch difference in tension generated by active muscle

Question 10

What do GTOs respond?

Answer 10

Tension activated/ generated by:
Muscle contraction, Passive Stretch

Question 11

GTOs protect muscle:

Answer 11

From excessive load

Question 12

If activated, GTOs…

Answer 12

Send impulses to elicit reflex inhibition

Question 13

GTOS inhibit

Answer 13

Muscle contraction
-causes muscle relaxation
-good for stretching (PNF)

Antagonist muscle is excited

Question 14

PNF

Answer 14

Proprioceptive Neuromuscular Facilitation

Question 15

What is Proprioceptive Neuromuscular Facilitation

Answer 15

A type of stretching where the GTO is first activated by a forceful contraction
-causes activation of GTO, which activates muscle contraction
-increases ability to stretch

Question 16

Neural adaptation

Answer 16

Alter motor unit recruitment
-increased motor unit firing, increased synchronization

Question 17

Bilateral Deficit

Answer 17

The sum of unilateral strength is greater than bilateral strength
-sum of the strength of each individual limb is greater than the strength of both limbs put together
-disappears with bilateral training, increases with unilateral training

Question 18

Causes of Bilateral Deficit

Answer 18

-sensory input from one limb causing inhibition on the motor neurons innnervating muscle of opposite limb
-possible inhibition of type 2 fibers/ decreased recruitment

Question 19

fMRI

Answer 19

Functional magnetic Resonance Imaging
-detects changes in oxygenated hemoglobin
(Indicates where there are increases or decreases in oxygen consumption in the brain