 The Daily Caller has a piece on this today. The behavior the Biden aides are describing can be compared to a symptom of dementia called sundowning. The term sundowning references a state of confusion that affects elders, particularly those with Alzheimer's disease or a type of dementia, during the evening or as the sun is beginning to set, according to the Mayo Clinic. More extreme cases of sundowning result in anxiety, aggression, pacing, wandering, even hallucinations and trouble sleeping, the Mayo Clinic states. So there you go.