Cognitive impairment

Domain : Symptoms

Category : My daily life

Simplified definition

A group of symptoms that affect brain and prevent a person from remembering, learning, communicating, or making decisions.

Source: Houria Aiouaz, for Alzheimer Foundation

Referenced definition

“Decline from a previously attained level of cognitive functioning.”

Source: Sachdev PS, Blacker D, Blazer DG, Ganguli M, Jeste DV, Paulsen JS et al. Classifying neurocognitive disorders: the DSM-5 approach. Nature Reviews Neurology. 2014 Nov;10(11):634-642.


Cognitive impairment can be classified into three severity levels: Mild (difficulty with instrumental activities of daily living), Moderate (difficulty with basic activities of daily living), and Severe (fully dependent on caregivers).”

Source: Johns Hopkins Medicine. Cognitive impairment. [Internet]. [cited on Sept 7, 2022]. 


  • Doctors may perform different exams, such as MMSE, to know if the brain’s functions are being affected.
  • Mild cognitive impairment (MCI) is an early stage of memory problems, which does not affect daily life and is not as severe as dementia. However, it can be a sign of Alzheimer’s disease.


Cognitive deficit



Cognitive impairment : RELATED DEFINITIONS


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