Chapter 5

1. Chapter 5 Motor Control Theories

2. Information flow during an action • Feedback guided control or closed-loop control

3. Information flow during an action • Planned control or open-loop control

4. The give and take of information flow • Better or worse • Flexibility • Type of action • Type of environment

5. Identify the flow of information controlling the action

6. What do theories provide? • A framework for understanding phenomena, outcomes, and processes, in a given field

7. What should theories of motor control and learning provide? • Explanations of what phenomenon! • Predictions for outcomes • Application

8. Essential components of a motor theory • What are the controlled variables? • How is the action controlled? • How does the process of coordination work? • What is the relationship between control and coordination?

9. Motor program theories • Central representation • Selection rules • How is a program assembled?

10. Schmidt’s Schema theory: 1) GMP • Generalized motor program (GMP) • What type of actions was the theory designed to explain?

11. Schmidt’s Schema Theory:2) MRS • Motor response schema (MRS) • Parameters - Selection rules • Degrees of freedom • Examples of GMPs and parameters

12. Writing your name • How many ways can you write your name?

13. Locomotion: stride analysis

14. 1500 60 50 1200 Step cycle duration (ms) 40 Percent of step cycle 30 900 20 walking running 600 10 3 4 5 6 8 9 10 11 12 Speed of locomotion (km/hr) walking running 0 3 4 5 6 8 9 10 11 12 Speed of locomotion (km/hr) Rhythmic actions and GMPs • Speeding up and slowing down:

15. Dynamic pattern theory: Key concepts • Self-organization • Attractor • Coordinative structure • Control parameter • Order parameter

16. Behavior without a detailed program

17. Keeping time

18. o 0 o 1 8 0 A B D A B D L e f t L e f t F i n g e r F i n g e r A D D A D D A B D A B D R i g h t R i g h t F i n g e r F i n g e r A D D A D D Dynamic patterns: self-organization in human motor skills • Can an order parameter be identified for human actions?

19. Right finger Left finger Dynamic patterns: non-linear change in an action A B D A D D 1.5 Hz 1.75 Hz 2.0 Hz 2.5 Hz Ab RH Ad Ab LH Ad Ab LH Ad

20. 1 8 0 6 0 1 6 0 ) ) g g 5 0 1 4 0 e e d d ( ( e D 1 2 0 s S 4 0 a h e s P 1 0 0 a e h v 3 0 P i 8 0 t a e l v e i t R 6 0 a 2 0 l n e a R e 4 0 M 1 0 2 0 0 0 1 . 5 2 . 0 3 . 0 2 . 5 D r i v i n g f r e q u e n c y ( H z ) Dynamic patterns: compare in-phase and anti-phase

21. 1 . 5 H z 1 . 7 5 H z 2 . 0 H z 2 . 2 5 H z A B D A D D P o s i t i o n o f R i g h t i n d e x f i n g e r P o s i t i o n o f L e f t i n d e x f i n g e r 5 0 0 m s Dynamic patterns: from muscle to limbs

22. Left-H. Right-H. Dynamic patterns: from cortex to limbs • Is there a transition in the brain? • Where does the instability (loss of stability) come from?

23. Interpersonal coordination skills • Schmidt et al. (1990) • Between person coordination • Two separate nervous systems • Visual input and motor output • Timing to an external event

24. 180 45 Standard deviation (VE) Mean relative phase 150 35 25 90 15 30 5 Increasing speed Tr Increasing speed Increasing speed Tr Increasing speed Interpersonal dynamics • What happened when movement frequency was increased?

25. Perceptual threshold • Smooth pursuit eye movements • Discrimination threshold • Track continuously up to 1.5 Hz • > 1.5 Hz Switch to fixed gaze

26. Dynamic pattern theory: key concepts • Perception-action coupling

27. Dynamic patterns – m:n

28. Multi-frequency (1:2): Is it really so hard? Time series Angle-angle Relative phase ext Left-arm flx LA ext flx flx RA ext Right-arm Right-arm left-arm • Control parameter Kovacs et al. (2010) Produce a 1:2 polyrhythm

29. Attention, multi-frequency (1:2)

30. Vision, multi-frequency (1:2) • Angle-angle/limbs covered • No angle-angle/limbs uncovered

31. Chapter 6 Touch, Proprioception and Vision

32. Perception-action • All actions require a transfer of perceptual information into motor commands • Closed-loop control • Open-loop control

33. Tactile sensations • Mechanoreceptors • Role in action control (closer look 109)

34. Proprioception: limb and body position and movement • Muscle spindles • Golgi-tendon organs (GTO) • Joint receptors

35. Deafferentation: • Surgical • Temporary • Neuropathy • Tendon vibration

36. Error (cm) Sensory neuropathy: loss of proprioception • Blouin et al. (1993) • Independent variables • Dependent variable

37. Sensory neuropathy: loss of tactile and proprioception • Bimanual coordination (Spencer et al. 2005) • Draw two circles

38. X-displacement Sensory neuropathy: loss of proprioception Vision of: • Patient findings

39. Vestibular system: head and body position and movement

40. Vestibular and visual systems: feedback control and balance • Task: • Kinematics: video cameras • Platform speed (Hz): • Feedback conditions

41. forward backward anterior 10 A/P Disp (cm) 0 posterior 10 secs -10 time trunk platform forward backward 10 A/P Disp. (cm) 0 -10 Vestibular loss: postural responses • Buchanan and Horak (1999); Buchanan and Horak (2002)

42. anterior 10 secs 2 secs posterior trunk platform Platform speed: postural responses • Postural behavior

43. Questions: • 1) How did the loss of vestibular information influence balance and posture? • 2) How did platform velocity affect balance and posture? • 3) What did visual information contribute to balance control?

44. Visual Fields: aligning vision (in) and motor (out)

45. Vision and motor control • Vision-for-action (dorsal stream) • Vision-for-perception (ventral stream) • Two distinct neural pathways

46. Vision and motor control • Reaching and grasping • Describe a cup (size, color, shape) • Reach for a cup

47. Vision and motor control • Optical field • Optical flow

48. Contact with objects:stationary and non-stationary • Estimate contact with an object STOP

49. Sensation and perception • Sensation - information pickup or selection • Perception - interpretation of sensory information

50. Same information – different perception! http://www.scientificpsychic.com/graphics/