What is Mild Cognitive Impairment? Expand Mild cognitive impairment (MCI) describes a set of symptoms involving problems with cognitive function. People with MCI often have difficulties with memory, but these are not bad enough to be defined as dementia. Some people diagnosed with MCI will go on to develop dementia, some will remain stable over time and a few people will improve and no longer have any problems. Although it can be the first sign of dementia, sometimes MCI will be diagnosed as a result of another condition such as anxiety or depression.