1. The inability to fix the range of a movement in muscular activity.

Rapid and brusque movements are made with more force than necessary.

2. The inability, in the performance of a movement, to judge direction and distance, seen particularly when the patient attempts to touch his nose or the examiner’s finger with his finger, or his knee with his heel.

The movement, while generally in the right direction, either veers to the side of the target or overshoots (hypermetria).