Ganglion Cell Types (IMAGE) University of Pennsylvania School of Medicine Caption Two broad classes of ganglion cell types in the guinea pig retina: brisk cells, which are larger and transmit electrical impulses faster, and sluggish, which are smaller and slower Credit Credit: Kristin Koch,University of Pennsylvania School of Medicine; Current Biology 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.