| Abstract: | Nonvisual perception of a hand-held object's length through wielding is known to be a function of the object's inertia tensor about a fixed rotation point in the wrist. The tensor is insufficient, however, to support perceptions of 2 different extents of an object in 2 different directions. The attitude spinor represents the tilt of the object's inertia ellipsoid relative to the hand in 2 oppositely oriented directions of rotation. Predictions about selective dynamic touch based on the spinor's 2-orientedness were confirmed in experiments in which participants wielded in 1 hand either (a) 2 rods, and attempted to perceive the length of one of them, or (b) 1 rod, and attempted to perceive the length of a part. (PsycINFO Database Record (c) 2011 APA, all rights reserved) |
