Traffic Light in the Brain (IMAGE) University of Freiburg Caption A photograph of a rat exploring a traffic light illustrating artistically the balance of motor inhibition (red light), preparation (yellow light), and execution (green light). Credit Photo: Michael Veit Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.