The mechanisms behind fear revealed (IMAGE) University of California - San Diego Caption New research published in Science identifies the brain biochemistry and neural circuitry that cause generalized fear experiences. Here, neurons are shown in cyan and retrograde tracers shown in yellow and magenta. Credit Spitzer Lab, UC San Diego Usage Restrictions Must be used in conjunction with Science paper on the brain and stress-induced fear License Original 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.