Making Connections (IMAGE) Cincinnati Children's Hospital Medical Center Caption This cross section image of the coronal brain region of a genetically mutant PlexA1 mouse shows evidence cortico motor-neuron cells eight days after researchers injected an altered rabies virus tracer into the animal's forelimbs. These connections are eliminated in normal wide mice as they mature. Scientists studying motor disabilities report in Science they blocked nerve pruning in the developing mutant mice, maintained these connections to adulthood. Credit Cincinnati Children's 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.