Reach and Grasp Scenario

• Object Identification:

  • Visual information about the characteristics of the object is used to:
  • improve accuracy of reach and hand shape
  • pre-programme the kinds of forces required for stabilisation
• Object Location:

  • Object in central vision – eyes only move
  • Object in near peripheral vision – eyes and head move
  • Object in far peripheral vision – eyes, head and trunk move
• Object Location:

  • Similar but separate mechanisms are involved in this process
  • Each can be assessed separately
  • Each may need to be trained separately
• Postural Component - consider:

  • the load (heavier = greater postural adjustment)
  • how far to reach (i.e. trunk movements extend reach)
  • Speed (e.g. catch fast moving ball) needs increased postural stability
  • If too far than must alter posture (e.g. sit to stand, or walk stand)
• Postural component - clinical ramification:

  • when we asses r&g, we need to assess in different directions e.g. more laterally, higher, lower
• DO VISION AND POSTURAL TESTS BEFORE MAIN ASSESSMENT