Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Kin 322 > Performance And Motor Control Characteristics Of Functional Skills > Flashcards

Performance And Motor Control Characteristics Of Functional Skills Flashcards

1
Q

Centre of mass (COM)

A

Weighted average of all segments in body, the body’s balance point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Centre of pressure (COP)

A

Point location of the vertical ground reaction force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Base of support (BOS)

A

The area defined by contact with a support surface
Area beneath an object or person that includes every point of contact that makes with supporting surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Margin of stability (MOS)

A

Distance between the COM position and the edge of the BOS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Equation for COM

A

Com= mi x ri / mi
MiRi = sum of segment masses x distance from reference
Mi= total mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

COP equation

A

COPx = Momentx / FORCEvertical
- average of pressures over the surface in contact with ground

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are examples of base of support

A

Body parts, feet or hands, or crutches, or chair person sitting on

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

To remain standing balance what must happen

A

COM must remain within the BOS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

During standing what happens

A

COP acts to control the COM and keep it within the BOS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens if the COM moves outside the BOS

A

BOS must be changes quickly to “catch” the COM or a fall will occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How to maintain dynamic balance (walking balance)

A

BOS must change to control COM movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Summary of balance control

A

To prevent fall, COM stays within BOS or projected into a forthcoming BOS
COP helps control the COM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How can stability be assessed

A

Measuring the margin of stability (MOS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is involved in control of locomotion (gait)

A

Central pattern generators (CPG) in spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is CPG in spinal cord provide

A

Basis for stereotypic rhythmicity of walking and running gait patterns (include arm swing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What else influences gait

A

Proprioceptive feedback from muscle spindles and GTOS
- timing of locomotive cycle
- size of muscle response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How do CPGs work

A
  • Motor signal from higher brain structures to CPG in spinal cord to extensors and flexors
  • Proprioception from flexors and extensors to CPG in spinal cord to higher brain structures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the rhythmic structure of locomotion

A
  • components of a step cycle
  • rhythmic relationship between arms and legs
  • pelvis and thorax relationship during walking
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the relationship between pelvis and thorax during walking

A

In at slow speeds
Out at higher speeds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the practical benefit of analyzing rhythmic structure of gait patterns

A

Allows for assessment of coordination problems of trunk and legs (ex Parkinson’s disease)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is another important motor control characteristic of locomotion

A
  • head stability
    Vestibular canals and vision both based in head
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What happens at critical speed

A

People spontaneously change from walking to running gait and vice versa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Why do spontaneous gait transitions occur

A

Most popular hypothesis: minimize metabolic energy use

24
Q

When walking or running what is vision important for

A

Enabling us to contact objects and avoiding contact with objects

25
Q

What vision control system is responsible for contacting objects

A

Tau (time to contact)

26
Q

How does vision help with avoiding contact with objects

A
  • provides advanced info to determine how to avoid contact - step over, dodge
  • provides body scaled info to determine how to walk through door, to step on a step
27
Q

What is the speed-accuracy trade off

A

When both speed and accuracy are essential to perform a skill

28
Q

When speed is emphasized

A

Accuracy is reduced

29
Q

When accuracy is emphasized

A

Speed is reduced

30
Q

Fitt’s law

A

Most significant laws associated with human movement
Mathematically predict movement time for speed accuracy skills

31
Q

What do we need to know for Fitt’s law

A

Spatial dimensions of 2 variables
Movement distance
Target size

32
Q

What else can be calculated base on Fitts law

A

Index of difficulty

33
Q

What is index of difficulty

A

Quantitative measure of the difficulty of performing a skill involving both speed and accuracy requirements

34
Q

Speed-accuracy skills: Fitts law

A

As target size becomes smaller or as distance gets longer, the movement speed will decrease in order for accurate movement

35
Q

Open loop

A
  • does not use feedback
  • initial speed, direction, accuracy under CNS control
  • at movement initiation, initial movement instructions are sufficient to move limb to vicinity of target
  • efferent info only (eg. Basketball freethrow)
36
Q

Closed loop

A
  • does use feedback
  • control center send only enough info to effectors to initiate movement
  • relies on feedback to continue and adjust if needed (eg. Dribbling a basketball)
37
Q

What 2 motor control processes underlie performance of speed-accuracy skills

A

Open loop control
Closed loop control

38
Q

Where is accuracy for closed loop control

A

At termination of movement

39
Q

What does Closed loop feedback need to hit target accurately

A

From vision and proprioception needed at end of movement to ensure hitting target accurately

40
Q

What is important in closed loop control

A

Whether person has time to make necessary corrections as limb nears the target

41
Q

What is the third phase proposed

A

Movement preparation phase

42
Q

Movement prep phase

A

Person uses vision to determine the regulatory conditions that characterize the environmental context in which action will occur

43
Q

Prehension

A

Reaching for and grasping an object

44
Q

3 distinct components of prehension

A
  1. Transport
  2. Grasp
  3. Object manipulation
45
Q

Transport

A

Movement of hand to object

46
Q

Grasp

A

Hand taking hold of object

47
Q

Object manipulation

A

Functional goal of prehension
- makes pretensions different from reaching and pointing
- influences characteristics of transport and grasp

48
Q

What does prehension demonstrate

A

Speed accuracy trade-off
- during transport phase, arm will accelerate and then decelerate
- as object size decreases, length of deceleration phase increases (longer to reach target)

49
Q

Biannual coordination skills

A

Motor skills that require simultaneous use of two arms

50
Q

What may biannual coordination skills require

A

Arms to move with same or different spatial and/or temporal characteristics

51
Q

Two types of biannual coordination skills

A

Symmetrical biannual coordination (clapping, lifting, rowing a boat)
Asymmetrical biannual coordination (playing musical instrument, patting head and rubbing stomach)

52
Q

What are motor control characteristics related to biannual coordination

A

The two arms prefer to perform symmetrically

53
Q

Three phases of catching a moving object

A
  1. Initial positioning of arm and hand
  2. Shaping of hand and fingers
  3. Grasping the object
54
Q

Two critical time periods in visual contact time needed to catch a moving object

A

Initial flight
Just prior to hand contact

55
Q

What visual contact is needed between the two critical periods

A

Brief, intermittent visual snapshots sufficient to make contact

56
Q

Ball speed effect

A

Skilled strikers demonstrate similar bat movement time for all ball speeds

57
Q

What visual contact with moving ball do skilled strikers do

A

Do not maintain throughout ball flight but visually “jump” from early flight to predicted location in area to strike ball
- head stability important

Kin 322 (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions