Encyclopedia of Gerontology and Population Aging

Living Edition
| Editors: Danan Gu, Matthew E. Dupre

Mild Cognitive Impairment

  • Aidan J. Murphy
  • John B. Williamson
  • Damon G. LambEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-69892-2_691-1



Mild cognitive impairment (MCI) refers to a decline in cognitive performance beyond that expected as a result of normal aging (See “Age-Related Cognitive Impairment”) without the loss of functional independence which is characteristic of dementia (See “Alzheimer’s Disease”). Any neuropsychological domain may be affected. MCI is an etiologically agnostic term and may or may not represent the manifestation of a neurodegenerative disease; however, it is a significant risk factor for developing dementia.


The term mild cognitive impairment (MCI) was originally developed as a clinical description corresponding to a clinically apparent gray area between healthy aging and dementia. At the time, it was recognized that the path from healthy aging to dementia was heterogeneous, often graded, and frequently reflective of an underlying neurodegenerative disease (See “Neuroscience of Aging”). It...

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Copyright information

© This is a U.S. Government work and not under copyright protection in the U.S.; foreign copyright protection may apply 2020

Authors and Affiliations

  • Aidan J. Murphy
    • 1
  • John B. Williamson
    • 1
    • 2
    • 3
  • Damon G. Lamb
    • 1
    • 2
    • 3
    Email author
  1. 1.Center for Cognitive Aging and Memory, College of MedicineUniversity of FloridaGainesvilleUSA
  2. 2.Brain Rehabilitation Research Center, Malcom Randall Veterans Affairs Medical CenterGainesvilleUSA
  3. 3.Center for OCD and Anxiety Related Disorders, Department of Psychiatry, College of MedicineUniversity of FloridaGainesvilleUSA

Section editors and affiliations

  • Adam J. Woods
    • 1
    • 2
  1. 1.Department of Clinical and Health Psychology, College of Public Health and Health Professions, Center for Cognitive Aging and MemoryMcKnight Brain Institute, University of FloridaGainesvilleUSA
  2. 2.Department of NeuroscienceUniversity of FloridaGainesvilleUSA