Book excerpt: "Case: This 68-year-old right-handed man was evaluated after an episode of delirium. Three months prior, in the span of two days, he became confused and agitated. At the hospital, he was found to have a urinary tract infection (UTI). Within three days after treatment, he returned to his baseline cognitive function and remained stable since. Although he initially reported no cognitive problems, upon further questioning he acknowledged word-finding difficulties and forgetfulness for at least the previous 2 years. His daughter reported that he repeated questions and stories"--