The hippocampus is critical to learning and memory. Patients with hippocampal atrophy often have difficulty with declarative memory (i.e. remembering facts, names, events, etc.) and making new memories. Hippocampal atrophy can be seen a variety of disease processes, including epilepsy and neurodegenerative disease. Note how atrophy in this elderly patient, who had memory difficulties prior to death, involves the right hippocampus more than the left giving the appearance that the lateral ventricle’s right temporal horn appears larger than the left.