A Rat's Imagined Trajectory from Point A to its Chocolate Reward at Point D (image) Johns Hopkins Medicine Share Print E-Mail Caption Unique combinations of the brain's place cells fire (red lights) in sequence to represent each part of the path (A, B, C, D) that the rat will take. This image was compiled over a few milliseconds. Credit David Foster, courtesy of Nature Usage Restrictions No restrictions as long as proper credit is given. Share Print E-Mail 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.