This photomicrograph shows the hippocampus and cortex of a 12-month-old transgenic mouse expressing human tau. The section is immunostained with a marker of pathological tau phosphorylation (red), NeuN (green), and DAPI (blue). For more information, see the article by Steuer, Kemper et al. (pages 4737–4754). Cover image: Elizabeth Steuer and the University Imaging Centers at the University of Minnesota.