Digital Brain (IMAGE) University of California - San Diego Caption Development of the fetal brain involves the creation and migration of billions of neurons during the course of pregnancy. Credit <a href="http://www.mertensdesignlab.com" target="_blank">Veronika Mertens</a> Usage Restrictions Use photo credit 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.