It is important to understand that the brain is continuously giving and receiving feedback. Information is always moving up and down the system and modifying both input and output. For example, the motor system sends out a signal to move and the left hand reaches out to grasp a glass. Simultaneously, the brain processes important sensory feedback. The hand is too far to the left of the glass, the pinky finger brushes against the back of a chair. This feedback is automatically incorporated into the ongoing movement, and the hand is moved half an inch to the right. The impact of this new movement is then encoded into new sensory information. For the sake of simplicity, our sensory and motor systems are presented here as if they act in isolation. In reality, though, the brain is a giant web of interacting systems giving itself constant feedback.