Other publications

What are neurocognitive disorders?

What are neurocognitive disorders? There are two types. Find out more.

By Maude-Émilie Pépin, Liaison and Support Officer, Major Neurocognitive Disorders Living Labs

Neurocognitive disorders (NCD) are characterized by a loss of mental faculties that reduces a person’s ability to care for him or herself independently.

Source: Quebec Federation of Alzheimer Societies, 2023

There are two types of neurocognitive disorders: mild and major.

Mild neurocognitive disorders


Mild neurocognitive disorders (MND) go beyond healthy cognitive aging and are characterized by changes in memory, language and reasoning. However, activities of daily living can be maintained independently by the person living with MCI.

Major neurocognitive disorders

“Major neurocognitive disorder” is an umbrella term, now used to group together numerous neurocognitive diseases, many of which were previously considered “dementia”. Source: MSSS, 2021

Major neurocognitive disorders (MND) inevitably lead to a progressive loss of cognitive function, which in the long term will result in the inability to perform activities of daily living and to make decisions concerning oneself.

Alzheimer’s disease is the most common form of non-reversible, non-curable cognitive impairment. However, there are several other types of cognitive impairment, such as fronto-temporal degeneration, Lewy body disease, cerebrovascular disease and mixed neurocognitive disorders. Source: Alzheimer Society Canada, 2021

Ministerial guidelines on major neurocognitive disorders

Over the past decade, Canada’s aging population has grown considerably. This increase in the number of aging people has led to a rise in the prevalence of Major neurocognitive disorders (MNDs).

As a result, the need to adapt services for people living with MNDs has become inescapable. In light of this observation, several experts were called upon by the MSSS to specify the orientations and actions required to promote the best possible care transitions.

In 2009, a ministerial action plan was proposed for Alzheimer’s disease and related disorders, covering all aspects of the subject, from prevention to research and end-of-life care. Source: Bergman, 2009; MSSS, 2021

To this end, the third phase in the deployment of the ministerial initiative on MNDs is underway. The work is constantly evolving, and is being built on the basis of best clinical and organizational practices.

Alzheimer et autres troubles neurocognitifs majeurs – Orientations ministérielles

Bergman, H. (2009). Relever le défi de la maladie d’Alzheimer et des maladies apparentées : Une vision centrée sur la personne, l’humanisme et l’excellence, Rapport du comité d’experts en vue de l’élaboration d’un plan d’action pour la maladie d’Alzheimer, gouvernement du Québec, 143p.

Institut national d’excellence en santé et en services sociaux. (2015). La maladie d’Alzheimer et les autres troubles neurocognitifs, Document synthèse : repérage, diagnostic, annonce et suivi, gouvernement du Québec, 25p.

Ministère de la Santé et des Services sociaux. (2021). Orientations ministérielles sur les troubles neurocognitifs majeurs : phase 3, gouvernement du Québec, 68p.

Organisation mondiale de la santé. (2012). Dementia: a public health priority, World health organization 2012, Genève, Suisse, 103p.

Orientations ministérielles sur les troubles neurocognitifs majeurs – Phase 3

Alzheimer Society of Canada. (2021). What is dimentia?