Differentiation is the ability to move one body part without the unintentional movement of other parts.
The ability to move ones eyes independently from the head is required for reading. Differentiation of fingers, one from another is needed for fluid writing. Differentiation also allows us to mentally prioritize and focus on the task at hand. Clues that may indicate a weakness in differentiation include:
- Difficulty sorting out fingers for fine-motor coordination.
- Startled reactions.
- Knocking things over at the table.
- Unintentional movement of the opposite hand when one hand is engaged.
- Unintentional movement of the legs when one hand is engaged.
- Movement of the tongue and/or mouth when concentrating.
- Tics that involve more than just the eyes.
- Unintentional body movement often interpreted by others as misbehavior when standing in line, sitting at circle time, etc.