Lecture 9: Proprioception

Question 1

Proprioception:

Answer 1

The sense of position and movement of one’s own limbs and body without using vision

Question 2

Proprioception is used when?

Answer 2

Used in the context of reflexive control

Question 3

Kinesthesis:

Answer 3

Involves consciousness

Question 4

Kinesthesis is used when?

Answer 4

Used during purposeful learning of a motor skill

Question 5

Kinesthetic of proprioceptive sensations include:

Answer 5

1. Sense of position and movement of the limb
2. Sense of force (effort, heaviness)
3. Sensation of body image and posture
4. The timing and magnitude of movements

Question 6

Muscle spindles as a source of proprioception:

Answer 6

Ia: Velocity
II: length

Question 7

Joint receptors as a source of proprioception:

Answer 7

Pressure, muscle contraction, extreme joint position

Question 8

GTOs as a source of proprioception:

Answer 8

Tension/force, sense of effort

Question 9

McCloskey experiment on reflexive control of movement:

Answer 9

Muscle tendon pulling experiments. Perceiving finger movement (during surgery)

Question 10

Goodwin experiment on reflexive control of movement:

Answer 10

Muscle vibration experiments.
- Vibration activates muscles spindles, causing illusions of joint movement and position

Question 11

Philips experiment on reflexive control of movement:

Answer 11

Found a cortical projection for Ia afferents, therefore potential role in kinesthesis

Question 12

Muscle vibration induces:

Answer 12

Illusion as if spindle firing has been perceived

Question 13

Goodwin’s experiment (in depth):

Answer 13

• Anesthetized index finger
• Ischemic block at wrist
• No sensory feedback from hand
• Moved fingers: Movement awareness (flexion and extension) persisted
• No effect on forearm muscles

Question 14

McCloskey experiment (in depth):

Answer 14

• Transected the tendon of the GT extensor
• Allowing the muscle to be stretched without any point pressure/movement
• Sensations of joint rotation were perceived in the direction of muscle stretch
• Illusory movements were also evoked as a result of vibration

Question 15

Inglis & Frank’s findings on muscle vibration:

Answer 15

• Limb matching task
• Right arm moved to target, left had to match
• Vibrated the antagonist and agonist muscles of the right arm
• Antagonist vibration lead to errors while agonist vibration did not

Question 16

Skin strain conclusions:

Answer 16

1. Skin strain patterns are used in the brain’s assessment of finger position
2. Cutaneous feedback can take precedence over muscle receptor afferent feedback
3. Skin strain may be perceived as joint movement rather than skin deformation

Question 17

Evidence shows that skin and muscle interact to produce:

Answer 17

Sense of position and movement