A person experiencing dementia may easily become overwhelmed and flustered. They may then have even greater difficulty than usual with remembering, with managing tasks and with functioning independently. They may become very anxious, angry, ashamed or distressed in other ways. The heightened emotion can then further interfere with their ability to ‘think straight’, to function well, and a ‘vicious cycle or circle’ may set in. This has been called a ‘catastrophic reaction’ and is discussed in Chapter 4 of my book. We all can have catastrophic reactions but people with impaired brain function are more likely than most to experience this distressing phenomenon.