Regenerated hair cycles properly (IMAGE) RIKEN Caption Top row: Hair regenerated using the NFFSE medium that contains five critical factors. Note the hair cycles 4 times (growth ? falling out ? new growth ? repeat). Bottom row: Hair regenerated on medium missing one of the critical ingredients. Hair only cycled once in this case. Credit RIKEN 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.