Alzheimer's disease is characterized by progressive cognitive and functional decline. Recently, there have been reports in the medical literature on artists who continued to paint while suffering from Alzheimer's. This article describes the changes that occurred in the work of three artists who suffered from Alzheimer's: William Utermohlen, Carolus Horn and Willem de Kooning. In the case of William Utermohlen (1935-2007), Alzheimer's disease was diagnosed at the age of 61. A series of 15 self-portraits that he painted during the years he suffered from Alzheimer's disease provide a rare opportunity to look into the world of an Alzheimer's patient, and testifies to sustained motivation to create, despite severe cognitive impairment. Although Utermohlen's portraits show distortions in proportion and defects in spatial organization that became more evident as the disease progressed, the portraits are characterized by an extraordinary ability to express emotion, as well as by originality: each is a new piece of work, not an attempt to copy a previous painting. Carolus Horn (1921-1992) was diagnosed with Alzheimer's disease at the age of 58. In Horn's paintings, from the time he was diagnosed, there is evidence of distortion in perspective, "primitive" style, lack of individual characteristics in depicting his subjects, more schematic drawing, and a preference for using reds and yellows. In the most advanced stage of the disease Horn was only able to scribble. Despite his cognitive and functional limitations, Horn continued to draw daily, even in the advanced stages of his illness, until shortly before his death. Willem de Kooning's (1904-1997) Alzheimer's was diagnosed in his late eighties. During the following years, he painted more than 300 abstract paintings, which art critics assess as among the finest and most sensitive artistic achievements in contemporary painting. Despite cognitive limitations, de Kooning was able to muster the concentration to continue painting. Common to these three painters was the continuous urge to create, despite considerable cognitive impairment. Their art enables us to have a close look into the world of Alzheimer's sufferers. Analysis of their artwork can help us to understand the type of cognitive impairment caused by ALzheimer's, as well as some neurological aspects of art creation.