REFLEX PT 2

Question 1

what’s the purpose of α-γ Coactivation

Answer 1

• when muscle stretced, refllex reaction is to contract it
• alpha motor neuron is responsible for sending neuroon to conttract it
• as muscle contracts, spindlle becomes slack, so it cant pick up on iinnfo on
  muscle length anymore
• so gamma motor neuron stimulates contractile ends of intrafusal fibers (the one
  part of the spindle), so if we contract both sides, it pulls the muscle tight again
  so even when muscle is in contracted state, we pick up on info of changing muscle length

Question 2

what happens in brain as speed and difficulty of a movement increase

Answer 2

the brain increases gamma motor output to increase the sensitivity of the muscle spindles, so muscle contractile force is maintained or increased

Question 3

where are Golgi tendon organs located

Answer 3

in myotendionus junction

Question 4

what do Golgi tendon organs do

Answer 4

help prevent muscles and tendons from tearing when subjected to potentially damaging stretching force, as well as help ensure smooth onset and termination of muscle contraction (by functioning at normal muscle tensions)

Question 5

what is reciprocal activation in Golgi tendon organs

Answer 5

activating opposite muscle in order to relax contracting muscle quicker (and relieve pressure on tendon)

Question 6

can the somatic reflex flexor-reflex override other reflex and/or be overridden

Answer 6

Overrides other reflexes from using spinal pathways at same time, BUT can be overridden if the stimulus is expected

Question 7

describe the site of stimulus of reflex

Answer 7

noxious stimulus causes a flexor reflex on same side, withdrawing the limb

Question 8

describe the site or reciprocal activation

Answer 8

at same time, extensor muscles on opposite side are activated

Question 9

what are superficial somatic reflexes elicited by

Answer 9

gentle cutaneous stimulation

Question 10

what are the two kinds of superficial somatic reflexes

Answer 10

plantar flexor reflex and abdominal reflex

Question 11

describe the plantar flexor reflex

Answer 11

causes curling of toes and foot inversion; Sole of the foot is stroked firmly on the outer side from the heel to the front
→ Plantar flexion

Question 12

describe the abdominal reflex

Answer 12

causes lateral movement of umbilicus as abdominal muscles on one side contract

Stroke skin of lateral abdomen above, to the side, or below the umbilicus

Reflex contraction of abdominal muscles in which the umbilicus moves toward the stimulated side

Question 13

whats the babinski reflex

Answer 13

extension upward and abduction of toes
Normal in infants, but a sign of brain/spinal cord injury or disease in older persons

Question 14

describe contraction intensity of abdominal reflex

Answer 14

Contraction vary in intensity
⁎ Absent when corticospinal tract lesions are present

Question 15

what are the somatic reflexes

Answer 15

somatic reflex, crossed-extensor reflex, flexor reflex

Question 16

what are the stretch reflexes

Answer 16

achilles reflex (ankle jerk),

Question 17

what are the superficial reflexes

Answer 17

abdominal reflex, plantar flexor reflex,

Question 18

describe the crossed-extensor reflex

Answer 18

somatic reflex (muscles contracting/reflexing without us thinking about it, even tho we have conscious control over somatic)
and its a withdrawal reflex and synapses with spinal cord

Question 19

describe Golgi tendon organs reciprocal activation

Answer 19

activating opposite muscle in order to relax contracting muscle quicker (and relieve pressure on tendon)