lecture14-08 - Describe how reaching and grasping abilities...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
    Describe how reaching and grasping abilities develop  in the first year of life.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
    Development of reaching Within first 2 weeks, already directing arm towards objects. Some crude control of reach direction. Improves by the 5th month; consistently touch targets. Won’t reach for targets beyond arm’s length. Catching and anticipating target motion at 6 months. Distance accuracy develops more slowly, improving by 7 months.
Background image of page 2
    QuickTimeª and a TIFF (LZW) decompressor are needed to see this picture. Increased use of visual feedback between 5 and 11 months
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
    Early reach movements Initially use the trunk & shoulder (proximal joints) to reach for objects; use elbow less frequently. When babies do make large movements, can’t control inter-segmental dynamics. So hand oscillates.
Background image of page 4
    Development of reaching Between 5 and 9 months see many changes to kinematics: 1) Straightening of the hand path 2) Reduced number of “submovements” 3) Reduced movement time
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
    Development of grasping Newborns have grasp reflex (clasp object brought against the palm) – disappears by 6 months. 5 months: hand does not orient to object until contact 9 months: hand orients prior to contact (note visual information about orientation is available at 2 months). Pre-shape for object size. Still adjusting grip force by 7-8 years (grip force larger for larger objects). Use palmar grasp until about 12 months – then use fingers to grasp. Corresponds to rapid increase in the rate of myelination of corticospinal tracts at 12 months – responsible for distal musculature.
Background image of page 6
    Describe Stratton’s experiment with inverting lenses. What are the implications?
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
    Adaptation to different relation between vision and movement. George Stratton
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 08/12/2008 for the course PSY 341K taught by Professor Gilden during the Spring '08 term at University of Texas at Austin.

Page1 / 25

lecture14-08 - Describe how reaching and grasping abilities...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online