hk 258 exam 2 Flashcards
what are the 4 components of manual movement?
- visually locating a target
- transporting the arm and hand
- grasping the object
- manipulating the object
how are all reaches not the same?
vary on different factors which impact how a healthy adult reaches for an object
what are the different factors for reaches?
-motives
-static or moving object
-weight
-distance
-sharp/smooth
-speed of reach
-how long it takes you
-accelerating/decelerating
what are the typical kinematic variables that are measured in reaching research?
-peak velocity
-accelerative/decelerative time
-movement time
-straightness ratio
-average velocity
-movement units
what is the importance of reaching?
-discovery
-independent exploration
-achieving goals
what are the 3 stages of reaching?
-preaching
-visual guided reaching
-visually elicited reaching
Is Prereaching random?
no, they are bad since the babies don’t have enough postural support
what are the characteristics of prereaching?
-vision not used to guide hands to objects
-no correction mid course
-do not preshape hand
-rarely contact the target object
when does Prereaching start?
0-4 months of age
what is the old view of prereaching?
waving their arms, but no intention
what is the new view of prereaching?
trying to reach for objects
when does visually guided reaching start?
4-8 months
what are the two pieces of evidence that demonstrate that infants pay attention to the location of their hand in relationship to the object at this stage?
-auditory cues
-propecepive cues
what is visual guided reaching?
when infants use vision to grasp objects
what was the reaching In the dark experiments?
infants don’t need to see their hand to reach for object
4 different conditions
-2 in light/dark room
- large object= reaches with 2 hands
-small object= reaches with 1 hand
do infants need vision in order to grasp objects at the visually guided reaching stage?
no
when does visually elicited reaching start?
9+ months
what is visually elicited reaching?
no longer uses vision of hand to guide reach
what are the characteristics of the visually elicited reaching stage?
-only minor corrections needed
-no comparison of hand and object position
what are the characteristics of the visually guided reaching stage?
-making corrections
-adapt reach in response to a distorted visual field
how do infants transition between these stages?
-infants have to learn about the capability of their own body
-obsessive practice
what are the factors that influence reaching kinematics
-properties of object
-goal of the reach
what is the impact of goal on reach kinematics
precise action vs. non-precise action
what is precise action
reaching for ball and put in cup
what is non-precise action
reach for balance and throw the ball across the room
what is the key difference in between precise and non-precise action
the declarative phase
can infants plan ahead
yes
-reach faster if throwing ball
-did not find difference in decelerating phase
do infants adjust their reaches based on the goal of the task
yes
-difference in peak sizes
-higher peak= speed in throwing balls
what is the precise action in adults
longer declarative phase
what is the non-precise action in adults
higher peak velocity
what is the non-precise action in infants
higher peak velocity
what is the purpose of goal kinematics in special populations
allows us to examine the Motor planning deficits that may exists in developmental motor disorders
why do we study planning a reaching in children with cerebral palsy
to see if motor planning deficits or planning in advance
do children with CP plan their reaching movements in advance
-no, they do not have the ability
-need to break a sequence of events into individual segments
what was the tower building study
-2 yrs olds
-tasks: build tower of blocks as tall as they could ( no more than 10 blocks)
-looking for the placement phase of the reach
How do the high-tower builders and low-
tower builders differ in their kinematic profiles
the high= reach peak velocity at early reach
the low= reach peak velocity 1/2 way through reach
What might this mean for their motor abilities
long term
if we are not good at something at a young age it stays with us.
Which muscle groups are responsible for producing fine motor movements
small muscle groups
-hand and fingers
Which muscle groups are responsible for producing fine motor movements
small muscle groups
-hand and fingers
Why is it important to have good fine motor skills
for sports, games, exercise, fitness, academics, social development, self-care
what are the 2 types of basic grasps in infancy
-palmer grasp
-pincer grasp
what age does palmer grasp start for small objects
4-5 months
what is the palmer grasp used for
fill ups objects with hand and fingers and thumb wrap around
what age does palmer grasp start for large objects
9-10 months
what age does the pincer grasp start
9-10 months
what is the pincer grasp used for
self feeding
what is the pincer grasp
thumb and index finger to pick up objects
Why are handwriting skills important in development
-intellectual thought processes
-visual and perceptual processing
-movement control
what happens in children lag in handwritting development
-lag behind in other areas
-tied to academic performance
-movement disorders
- ASD
How do handwriting and drawing abilities development over time?
-simple scribbles
-shapes
-letters
what are the gender differences in handwriting and drawing development
girls show better legibility and speed of handwriting
what is the timeline of handwriting and drawing development
-improve in handwriting in 1st grade
-3rd grade is automatic skill
what are the external factors in handwriting performance
-sitting position
-chair and desk configuration
-type of writing implement
-environmental factors (light and noise)
-type of instruction
-amount of practice
what are the 3 stages of holding a writing implement
-supinated grasp
-pronated grasp
-tripod grasp (static, dynamic)
supinated grasp
-12-18 months
-hand in supine
(palm up, fist like grasp
-controlled by shoulder joint
pronated grasp
-2-3 yrs
-palm downwards
(index finger and thumb straight and fingers wrapped around)
-controlled by elbow joint
static tripod
-4yrs
- thumb, middle, index, finger
-controlled by wrist joint
dynamic tripod
-6/7 years old til adults
-thumb, middle, index, finger, (C shape)
-controlled with fingers
How does the proximodistal rule of motor development apply to the stages of
holding a writing implement
growth/control of segments of human body proceeds from the center/midline toward the periphery of the body/farthest from the body’s center (shoulder= center, fingers=distal)
How does the appearance of letters change as children transition through the
stages of holding a writing implement
-prontate= all uppercase and big letters
- static tripod = uppercase but smaller letters
-dynamic tripod= lowercase
When do children first write in lower-
case
in the dynamic tripod stage
what are the 4 stages of drawing
-scribbling
-combine
-aggregated
-pictorial
scribbling stage
-controlled from shoulder joint
-scribble accidentally
combine stage
-palm down
-elbow joint
-simple shapes/lines
-combine simple shapes together
aggregated stage
-control from wrist
-combine simple shapes together
-more complex
pictorial stage
-more pictures and complex
-control with fingers
why do children with ASD have difficulties in gross and fine motor and postural control with handwriting
coordinate and control
why do children with ASD have difficulties in sensory function especially proprioception with handwriting
can’t get it to be automatic process
can’t watch fingers as they write
why do children with ASD have difficulties visual perception with handwriting
how they see the wold
- difficult to focus on big picture
-too detailed oriented
how are children with ASD handwriting ability measured
legibility and speed
-they put a string of words together that dont make sense
-no spacing of letters
external threats to balance
happen to use outside in our environment (slip and fall, trips)
internal threats to balance
treats that we cause ourselves
external balance characteristics
-feedback control
-sensory info
-control our balance
internal balance characteristics
-feed forward processing
- anticipatory postural control
- stabilize body first before we preform movement
postural control
stable when the body’s center of mass is within the base of support
how do you measure postural stability
force plate and kinematic cameras
what does postural stability measure
-amount of postural sway
-anterior-posterior and medial-lateral direction
what happens if you have more postural sway
less stable
what happens if you have less postural sway
more stable
what does postural stability on a EMG do
how fast the postural muscles fire in response to perturbation (more stable)
factors that influence postural stability
-age
-muscle strength
-neural integrity
-skeletal health
-sensory acuity
-cognitive ability
responding to external threats to balance
-sensory system’s contribution to postural stability
-movement strategies to maintain balance
what sensory system contributes to postural stability in adults
-vestibular
-visual
-proprioceptive
what is the rules on posture in adults
1) what is the support surface
-more stable on solid
- if same surface go to 2
2) what is visual condition
-more stable with full vision
-less with no vision
- worse with inaccurate visual
who is more stable: both have no vision, but on is on foam surface
the one without the foam surface
who is more stable: both on foam surface, but one has inaccurate vision and one has no vision
the inaccurate one
who is more stable: one is with vision but on foam surface, one only has inaccurate vision
the one with inaccurate vision
what are the 3 strategies to maintain balance
ankle (small)
hip (medium)
stepping (large)
how should the postural muscles fire in ankle strategy
-most distal fires first: leg, thigh, trunk
-depending on direction impact which side fires first
how should the postural muscle fire in hip strategy
-upper body
-thigh and trunk fire at same time
-only one side fires at time (forward/backwards)
A college student slips on an icy sidewalk, medium threat to their balance. what strategy do they use, and what does the muscle firing pattern look like?
hip strategy
upper body
An adult is pushed while waiting in line, small threat to their balance. what strategy do they use, and what does the muscle firing pattern look like?
ankle
distal
anticipatory postural control in adults
-activates postural muscle first (stabilize body)
-then prime mover muscles (perform the action)
development of posture in children
necessary for development in motor milestones
body proportions and balance for babies
it is a problem due to their higher COM and smaller BOS
external threats to balance in children
-sensory system controlling balance
-movement strategies to maintain balance
internal threats to balance in children
anticipatory postural control
at what age are children more visually dominant than adults
4-6 yrs
at what age are children strategies like adult’s
after 7yrs
anticipatory postural control in babies
-activate trunk first then deltoids