Over the past few decades, several researches have become interested in the problematic of those having cognitive disorders linked to various pathological conditions such as arteriopathic or Alzheimer-type dementia. Too many, however, have questioned the emotional and sex life of these same people. In this article, we shall first try to clarify the concept of sexuality and emphasize the reality it underlies. Next, we shall recall the changes connected to aging in terms of sexual response, body image, identity and other components of sexuality. We shall then put forward observations concerning the expression of sexuality by the dementia sufferer, who, to be honest, is quite often an older person as well. Lastly, we shall illustrate our point by reporting a fragment of Ms Rose’s story, the story of a person suffering from cognitive disorders, and conclude with some comments raised by this story.