Leture 6

Question 1

exteroception

Answer 1

• provides info to the processing system about the state of the environment in which ones body exists
• inherent feedback (directly available to us)
• info sources: vision and hearing

Question 2

proprioception

Answer 2

• provides info about the state of the body itself
• inherent feedback
• info sources: vestibular apparatus: helps you know where upright is, joint receptors: info on extreme joint positioning, muscle spindles, golgi tendon organs, cutaneous receptors: skin, pressure, temp, touch
• the CNS is thought to use a complex combination of the inputs from these various receptors as a basis for body awareness
• perception of a movement’s trajectory can be affected by how the movement is produced (actively or passively)

Question 3

closed loop control system 4 parts

Answer 3

1. An executive system: decisions about errors in our movements
2. An effector system: for carrying our that decision
3. A comparator: take actual feedback and compare to anticipated feedback and gives you the amount of error
4. An error signal

Question 4

limitations of closed loop control system

Answer 4

1. The inclusion of stages of info processing in the system illustrates the following:
   - the flexibility in movement control
   - a big disadvantage at the same time: slow process, high demand

Question 5

tracking tasks

Answer 5

• driving
• the system can produce corrections at a max rate of about 3 per second
• each correction is based on a collection of info about the errors that have occurred over the past few hundred milliseconds and goes through the stages of info processing
• tracking with more than 3 changes in direction per second is performed poorly
• closed loop tasks are better more slower movements/ reaction times

Question 6

rapid discrete tasks

Answer 6

• a feedback based view of movement control fails to account adequately for movement production in very quick skills
• kicking or throwing a ball
• texting
• feedback arising from the rapid movement would not have enough time to be processed before the movement was completed, which led scientists to believe that most rapid movements must be programmed in advanced