Biologists have long considered cells to function like self-cleaning ovens, chewing up and recycling their own worn out parts as needed. But a new study shows that some nerve cells found in the eye pass off their old energy-producing factories to neighboring support cells to be 'eaten.' The find, which may bear on the roots of glaucoma, also has implications for Parkinson's, Alzheimer's, amyotrophic lateral sclerosis and other diseases that involve a buildup of 'garbage' in brain cells.