motor development

Question 1

dynamic system theory - DST approach

Answer 1

modern approach used motor development and looks at how behaviour changes over time

emphasizes that multiple causes to different behaviour
e.g. being able to walk involves
increased in strength and weight, neural mechanisms, posture control, balance,perceptual skills and motivation

Question 2

major milestones of motor development - birth to 5 months

Answer 2

stepping reflex

mini push up during tummy time

bounce when held upright

Question 3

major milestones of motor development - 6 to 10 months

Answer 3

sit up
crawl
stand with support
cruise

Question 4

major milestones of motor development - 9 to 15 months

Answer 4

pull to a stand
stand unsupported
take first steps

Question 5

major milestones of motor development - 16 to 18 months

Answer 5

dance
climb stairs with help
walk backward

Question 6

adolph et al 2008

Answer 6

motor skills do not suddenly turn on and data collected may not be consistent

this study showed graphs of infants ability to stand independently for 3 secs

showed daily and monthly measures

monthly measurement was a simple looking graph that showed that they weren’t able to then they were

where as the daily measurement showed days before the recorded month measure that some days they could and some days they could and then after they could consistently stand

Question 7

fine motor skills

Answer 7

grasping
object manipulation
drawing

involve smaller muscles
(gonsales et al 2019)

Question 8

gross motor skills

Answer 8

sitting
reaching
crawling
walking
running

involve large muscles
(gonsales et al 2019)

Question 9

stepping reflex

Answer 9

(spencer et al 2006)

coordinated behaviour that resembles walking

alternating leg movements

disappears around 2 mo of age

Question 10

why does the step reflex disappears ?

Answer 10

rapid weight gain causes legs to get heavier faster than they get stronger

DST demonstration (link to the reading) - make babies behave like other babies:
oldier babies in water
yonder babies with ankle weights

shown that it is not just neurological maturity because they can do the same behaviour when laying down

Question 11

sitting independently

Answer 11

• no support from arms aids reaching (spencer et al 2000)
• sitting independently has a cascading effect on infants perception (ross-sheehy et al 2016)
• sitting creates new opportunities for exploring
• new opportunities for exploring shape visual perception

Question 12

figure ground assignment

Answer 12

allows us to identify objects from the background

it helps us understand depth and plan reaching

adults use symmetry convexity lower region to determine figure ground

infants need to figure ground segregation to guide attention eye movement and learning

• ross sheehly et al 2016

Question 13

ross sheehly 2016- figure ground assignment methods

Answer 13

a consistent and inconsistent video example - based on symmetry

showing that the background is what we would picture or not -stretch

two cues to figure:motion and symmetry

both screens had motion (both in front or both behind) difference in symmetry

Question 14

ross sheehly 2016 findings

Answer 14

when children were capable of sitting they were better at telling the difference between the consistent items and inconsistent items

“a significant preference indicates sitting infants perceive symmetry as a cue to figure ground assignment”

Question 15

rohr et al 2021 - reaching and grasping

Answer 15

stretching out one or both hands towards something to touch or grasp at it

initial reaches are swiping movements

reaching becomes stable after independent sitting
with increased experience.

more signs of anticipation in grasping - match hands to size of object

Question 16

soft assembly

Answer 16

the idea that you have a lot of components are coming together in a moment - they are assembling in different ways

example of elements for grasping
locate the goal object
stable base
controlled arm extension
variable timing: need all components to assemble into a successful reach

Question 17

sticky mittens

Answer 17

are a technique to help prevent flailing and assist teaching the child grabbing and reaching movements

have velcro that help children who are not yet reaching make contact with objects
(babies mitten have soft side and object have hook side)

Question 18

libertus and needham 2010

Answer 18

sticky mittens
10mins a day for 2 weeks - one for training

after 1 week the infants in the training group (mittens) grasps and reached significantly more often than their peers

effects persists for 12 month

but see williams, gorbetta and Guam 2015 - non-sticky mittens had higher performance

Question 19

Piaget - A, not B task

Answer 19

piaget thought that babies thought that something didn’t exist once out of their vision
so created the A-not-B task to test 8 to 10 month infants representations

in this test there are 2 hiding places and label the side where an object is hidden a and the other b
then give to the child to find the object
repeat
by trail 7 normally you switch to hid the object behind b in front of them

found they will still reach for 1 - motor response that they have learnt not that they have forgot about it

Question 20

DST account of A not B

Answer 20

• behaviour is the product of past history just previous past and present - nested timescales
• A not B error is the result of previous attention to A and practice reaching to A
• DST explanation includes attractors, motor memory and perservation
  error persist if there is no reaching on A
• there is no object, unmarked location
• there is long delay
  if you change posture between trials errors are reduced as less reliant on motor memory - made to stand

can get adult to do it - predural memory

Question 21

self locomotion

Answer 21

at around 8 months infants become capable of self-location

infants begin walking independently around 13 to 14 months (with a toddling gait)

Question 22

gibson and locke 1960

Answer 22

visual cliff
after first learning to crawl babies will cross but after a couple of weeks will no longer cross the drop off
actually happens because of a development in deep perception not because of a fear of heights

can actually test fear of height with an actual drop to see if they will lower themselves down

( a level - mothers on other side looking worried or encouraging )

Question 23

adolph 1997 - motor skills are context dependent

Answer 23

tracked infants in a weekly longitudinal study from early crawling to proficient walking

knowledge does not transfer from crawling to walking

67% of children plunged down all slopes but did become more cautious with experience

knowledge is context dependent

Question 24

hen and adolph (2020 wiley) - the importance of falling

Answer 24

falling (error in balance and motor control) may help us understand the role of errors in early development

138 toddlers - 13 to 19mo - were observed in lab playroom
toddlers fell 563 times in this study
so fall way more often than we realise - as they normally just get up as it is so normal for them

results
- falling didn’t alter subsequent behaviour
-after a fall, infants returned to play in 1.84 seconds on average
- impact was mitigated by small body size and infants quick reactive behaviours e.g. bracing with hands

only 4% of the time did they get upset and caregivers were only concerned 8% of the time

walking experience didn’t impact infant or caregivers reaction

frequent and low impact errors encouraged further practice

Question 25

road crossing - Dr.neal et al 2018

Answer 25

children 5 to 14 years have higher rates of pedestrian injuries than any other age group

Question 26

road crossing - Oakley et al 2012

Answer 26

most child pedestrian injuries happen at mid block

Question 27

road crossing - benner and yiannakoulias

Answer 27

shorten path to school often requires crossing mid-block

Question 28

road crossing - O’Neal et al 2018

Answer 28

6 to 10yr children are much slower than older children and adults to enter a road and also enter roads with much smaller gaps in traffic

Question 29

o’neal et al 2018 - road crossing simulation

Answer 29

3 screens with the visual cues of a real life situation

timed gaps between the fake cars

one ways street

children cross with a lot smaller gap than what adults perceive as safe

Question 30

o’neal et al 2019 - road crossing with friends

Answer 30

• pairs of friends crossed a virtual road 30 times (half on left/right)
• a steam of traffic came from the left at 40kmh (25mph)
• traffic included random 2 to 5 sec gaps
• no instructions to cross together or alone

they could wait to cross as long as they wanted to

Question 31

results of crossing roads with friends

Answer 31

adults vs 12 year olds

were more likely in general to cross if there was a bigger gap in the traffic

were more likely to cross in the small/ riskier gaps if they were with a friend rather than being alone

to compensate for short gaps they entered and crossed faster

when solo, the first of the pair to cross were more risky

in general 12 yr olds were more risky than adults