Figure 2. The median (10 subjects) effect of passively grasping the artificial finger on perceived vertical spacing between the index fingers.

Results of the grasp effect when (A) the test index finger and the grasping index finger and thumb were intact, and (B) the digital nerves of these digits were blocked. Perceived index finger spacing was reduced significantly when subjects passively grasped the artificial finger and all digits were intact (P= 0.007). When the test index finger and grasping index finger and thumb were blocked, a passive grasp of the artificial finger did not significantly change perceived index finger spacing (P= 0.065). Results are shown as median ± interquartile range.