As we age, our mind, like the rest of our body, changes. This is normal, but some people experience more dramatic changes than others. Dementia is a broad term that refers to a decline in mental ability severe enough to interfere with daily life. It can cause problems with memory, language skills, judgment and other cognitive functions. Some people may have difficulty remembering recent events or following directions, while others will require help performing everyday tasks, like dressing or managing medication properly.