In this stage signs and symptoms may be subtle. Often, the early signs become apparent when looking back. 70% of those diagnosed with MCI later progress to dementia. In MCI, changes in the person's brain have been happening for a long time, but symptoms are just beginning to appear. These problems, however, are not severe enough to affect daily function. If and when they do, the diagnosis becomes dementia. They may have some memory trouble and trouble finding words, but they solve everyday problems and competently handle their life affairs.