Brain slices of older tissues prepared with ice-cold (blue) and warm (red) preparation methods, as demonstrated by Shiwei Huang and Marylka Yoe Uusisaari in a paper in Frontiers in Cellular Neuroscience. The asterisks (*) indicate visible neurons. While no healthy neurons are visible in the left image, seven are visible in the right. Abbreviations: PN, Purkinje neuron layer; ML, molecular layer; GrC, granular cell layer.