Chapter 7: Manipulative Skills

Question 1

Gross Motor Development:

Answer 1

Movements requiring large musculature

Control over action that help infants get around in the environment such as crawling, standing and walking

Question 2

Fine motor development:

Answer 2

Movements requiring small muscles typically involved in hand-eye coordination, and precision of the hand and fingers
Smaller movements such as reaching and grasping

Question 3

grasping

Answer 3

Opening and closing hand

Question 4

Prehension:

Answer 4

The act of coordination reaching and grasping

Either with one hand or two hands

Question 5

Pre-reaching?

Answer 5

newborn

Question 6

reaching with ulnar grasp

Answer 6

3-4 months

Question 7

transfer objects from hand to hand

Answer 7

4-5 months

Question 8

Pincer grasp

Answer 8

9 months

Question 9

3 Major Periods of reaching:

Answer 9

Pre-reaching (birth - 2 months).. Stereotypies??
Successful reaching (2-9 months) 
Skillful reaching (9 months +)

Question 10

What aids in reaching?

Answer 10

Vision!

Visually Elicited:
Vision used to localize an object
Reach is executed without additional visual information
Sometimes called “triggered” or “elicited”
Visually Guided
Vision used during the reach, to guide the hand to the target
Infants may be looking at the target rather that the hand and the target during the reach

Visual stimulation:
Moderate amounts of visual stimulation tailored to a young baby’s needs results in earlier development of reaching
Movement encourages pre-reaching (i,e, the more the baby moves, is allowed to move.. More likely that they will show reaching behaviors earlier)

Question 11

Pre-reaching:

Answer 11

Birth to 2 months
Visually elicited
No grasp; not successful
Increases when the infant can fixate track moving objects
Postural support of trunk affords arm extension

Question 12

Successful reaching?

Answer 12

2-9 months
successful (obtain object) but not particularly smooth
visually guided - feedback dependent
reach is uncoupled from grasp

Question 13

Skillful reaching

Answer 13

9+ month
accurate, smooth
visually elicited - can use feedback
beginning of coordination of reach and grasp (prehension) are coupled
it takes many years before truly skillful reaching occurs

Question 14

Hand-Mouth Movements:

Answer 14

At 3 to 4 months, infants become consistent in moving the hand to the mouth
by 5 months, they open the mouth in anticipation of the hands arrival

Question 15

Study of reaching in 5,6, 9 and 13 month olds vs. adults (Von Hoftsen and Ronnqvist, 1988)

Answer 15

infants grasping was controlled as early as 5-6 months
9-13 month olds adjusted the opening of the hand with relation to the size of the object
13 month old initiated their grasp farther from the target in a timing sequence similar to adults than any of the younger groups

Question 16

Types of Grip (in developmental order)

Answer 16

1. Palmar (first grip, emerges out of grasp reflex)
2. Power (thumb in opposition but still palm, ~ 5-6 months)
3. Pincer/Precision (~9-10 months)
   Can shape hand to objects

Question 17

How many possible grip configurations can the hand do?

Answer 17

1013 potential combinations

Question 18

Bimanual Coordination:

Answer 18

At two months, infants show bilateral arm extension and reaching
At around 4.5 months, infants reach for objects with both arms
During year 1, infants alternate between predominantly unimanual and predominantly bimanual reaching
By 12 months we see pulling apart and insertion actions
Early in year 2 infants use objects as tools
After 18 months, infants manipulate objects cooperatively with both hands
By the end of year 2 we see complementary activities

Question 19

Catching:

Answer 19

Ideally objects are caught in the hands so they can be manipulated
Needing to intercept an object makes catching more difficult
Children initially position arms and hand rigidly, sometimes trap ba against chest
Children sometimes turn their head away or close their eyes

Question 20

Proficient catching

Answer 20

Hand give with the ball to gradually absorb the force
Catcher moves from side to side or forward and back to intercept the ball
Fingers are pointed up for highball and down for low balls

Question 21

Developmental changes in catching: Arm action

Answer 21

Little response
Hugging
Scooping
Arms “give”

Question 22

Developmental changes in catching: Hand action

Answer 22

Palms up
Palms in
Palms adjusted

Question 23

Developmental changes in catching: body action

Answer 23

No adjustment
Awkward adjustment
Proper adjustment

Question 24

Anticipation:

Answer 24

Is involved in many manipulative tasks and interception skills
Studied often involve coincidence-anticipation task (anticipating completion of movement to coincide with arrival of moving object)
Interception success is often related to ball size, speed, trajectory, and other task and environmental constraints
Children learn to arrive at the right place from their experiences with cathing. Both successful and unsuccessful catches contribute to learning the relationship between the visual information and body position