Proprioception. Definitions and Introduction.

Question 1

What is ataxia?

Answer 1

A loss of unconscious/conscious proprioception that leads to uncoordinated movements.

Question 2

What is an autonomous zone?

Answer 2

The area of skin innervated by a plexus nerve.

Question 3

What is a dermatomal map?

Answer 3

A map that highlights all of the different dermatomes in the body.

Question 4

What is a dermatome?

Answer 4

The area of skin innervated by the dorsal cutaneous branches of the spinal nerves.

Question 5

What is the dorsal column?

Answer 5

The spinal tract used for the flow of conscious proprioceptive information.

Question 6

What is the dorsal cutaneous branches of nerves?

Answer 6

Small nerves that branch off a spinal nerve and travel to the skin to innervate a small area.

Question 7

What are plexus nerves?

Answer 7

Nerves that branch off a plexus.

Question 8

What is proprioception?

Answer 8

The perception/awareness of the positioning of various parts of the body.

Question 9

What is sensory ataxia?

Answer 9

A loss of postural responses and/or gait without a loss in muscle strength.

Question 10

What are spinal nerves?

Answer 10

Nerves that branch off the spinal cord.

Question 11

What is the spinocerebellar tract?

Answer 11

The spinal tract used for the flow of unconscious proprioceptive information.

Question 12

What is proprioception?

Answer 12

The ability to tell where parts of the body are in space and where certain body parts are in relation to the body.

Question 13

What is proprioception essential for?

Answer 13

Co-ordinated and purposeful movements.

Question 14

What kind of movements are unconscious?

Answer 14

Automated movements such as walking.

Question 15

Unconscious movements can be described as what kind of motor skills?

Answer 15

As gross motor skills.

Question 16

What characterises skilled movements?

Answer 16

They are very precise.

Question 17

Are skilled movements conscious or unconscious movements?

Answer 17

Conscious.

Question 18

Conscious movements can be described as what kind of motor skills?

Answer 18

Fine motor skills.

Question 19

What does a loss of conscious and/or unconscious proprioception lead to?

Answer 19

Ataxia.

Question 20

What 3 things are constantly monitored by sensory proprioceptive receptors?

Answer 20

Muscle length.

Tendon length.

Joint angulation.

Question 21

What part of a muscle is used by sensory proprioceptive receptors to monitor muscle length?

Answer 21

Muscle spindles.

Question 22

What part of a tendon is used by sensory proprioceptive receptors to monitor tendon length?

Answer 22

Various parts of the tendon.

Question 23

What part of a joint is used by sensory proprioceptive receptors to monitor joint angulation?

Answer 23

Various receptors in the joint.

Question 24

What kind of ion channels are found in the neurons are the sensory proprioceptive neurons that are found in muscles?

Answer 24

Mechanically gated ion channels.

Question 25

What do the sensory proprioceptive neurons found in muscles prevent?

Answer 25

Over-stretching of muscles.

Question 26

What muscle is the patellar reflex associated with?

Answer 26

The quadriceps muscle.

Question 27

How do we initiate the patellar reflex?

Answer 27

We tap the patellar tendon and the quadriceps muscle is stretched. The movement is picked up by the receptors in the muscle spindles.

Question 28

What happens during the patellar reflex once movement of the patellar tendon has picked up by receptors in the muscle?

Answer 28

Mechanically gated channels open and the neuron depolarises. If there is no inhibitory input onto the nerve fibres then there will be an exaggerated response.

Question 29

What organs within a tendon monitor the degree of stretch and contraction of tendons?

Answer 29

Specific receptors called golgi organs.

Question 30

Where in tendons are golgi organs found?

Answer 30

In specialised collagen fibres within the tendon.

Question 31

How are the golgi organs within a tendon activated?

Answer 31

As the fibres are stretched they opening mechanically gated ion channels to trigger an action potential.

Question 32

Why are golgi receptors likely to respond to the contraction of a muscle?

Answer 32

As muscle contraction puts the most strain on a tendon.

Question 33

Where are golgi organs found in relation to the tendon and the muscle?

Answer 33

At the junction between the tendon and the muscle.

Question 34

What are motion receptors?

Answer 34

The receptors in joints.

Question 35

Where are motion receptors located?

Answer 35

Around joint capsules.