Abnormal central sensory function Impaired two-point discrimination 2012-04-28T02:50:12Z A reduced ability to distinguish tactile sensations at points that are very close to one another. This can be tested by using special calipers whose points can be set from 2mm to several centimeters apart. UMLS:C4023178 HP:0011810 A normal individual can sense about a 3 mm separation of points on the fingertips.