Chapter 2. Prehension

160
50 1
THE PHASES OF PREHENSION
1500-1
lL!
0 50 wrist 1
NORMALIZED TIME
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Figure 5.19 Perturbations of object direction. Top row:
Kinematics of transport of the wrist (dark line) and grip aperture
(light line) for perturbed-left, control, and perturbed right
conditions. Note the compensations to perturbation in both the
grasp and transport kinematics. Bottom row: Spatial paths and
their variability for the wrist (W), index finger (I) and thumb (T).
Note the greater contribution of the index finger than the thumb to
enclosing, but that this varies with condition (reprinted by
permission from Jeannerod & Marteniuk, 1992).