This 77-year-old man presented with a 6-year history of worsening short-term memory and urinary urgency. He first noticed difficulties multitasking and remembering long lists, with significant benefit from cueing. He later noticed word-finding difficulties and would lose track of the topic of conversation. Around that time, he began experiencing worsening urinary urgency, followed by incontinence. Two years prior to his evaluation, his gait became increasingly slower, leading eventually to multiple falls. He also became withdrawn and more irritable. On exam, he exhibited symmetric bradykinesia, rigidity, and postural impairment. His gait was wide based with external rotation of the feet and inability to tandem walk (Video 42.1). His brain MRI was interpreted as showing asymmetric cortical atrophy with asymmetric ventriculomegaly (Image 42.1). Given an ostensible presentation with memory impairment, and suspected atrophy on imaging, Alzheimer disease (AD) was diagnosed and he was started on a treatment trial with donepezil.