By: Iris Zhao
Major Neurocognitive Disorder
What is Major Neurocognitive Disorder?
Major neurocognitive disorder (MND) is the medical term for dementia. It refers to a collection of symptoms that results in a progressive loss of cognitive functioning, specifically in areas of thinking, memory, mood, and behavior. In most cases of MND, individuals are aged 65 or older. This deterioration in cognitive memory and skills can significantly impair an individual’s day-to-day functioning and affect their ability to participate efficiently in daily activities.
(Cleveland Clinic, 2025; Emmady, 2022; Mayo Clinic, 2025)
Causes
In most cases, MND is caused by damaged nerve cells, and the loss of nerve cells and their connections within the brain. This damage or loss of brain cells usually comes from a neurodegenerative disease that slowly harms brain cells over time. Healthy brain cells normally send electrical signals to each other to help the brain manage and function properly; however, when these cells are damaged or lost, it can interfere and block electrical signals which prevents the brain from working properly. As a result, this can negatively impact areas of the brain that are responsible for memory, learning, language, and decision-making. Certain illnesses or medication reactions may also cause and exhibit MND-like symptoms.
Alzheimer disease would be the most common cause of dementia, as people with Alzheimer disease have plaques or clumps of a protein (beta-amyloid) in their brains. These clumps are fibrous masses that are made of tau protein that form toxic tangles in the brain. They can, as a result, damage healthy brain cells and also damage the fibers that connect one’s brain cells. Alzheimer disease can be passed down from parents to their child which also increases the risk of the condition.
Some other factors that may contribute to the risk of developing MND consists of:
- Age: Although MND may occur in younger age groups, the risk of MND is higher as you age especially after 65 years old.
- Family history: If a family member has or has had MND, it puts you at greater risk of developing the condition.
- Down syndrome: By middle age, many people with Down syndrome may develop early-onset Alzheimer’s disease that contributes to causing MND.
- Depression: Having depression during adulthood may also be a risk factor for developing MND.
- Alcohol consumption: Drinking large quantities of alcohol has long been known to cause brain changes, and researchers have found this being linked to an increased risk of MND.
- Head trauma: People who have had severe head trauma exhibit a greater risk of Alzheimer’s disease.
- Low levels of vitamins and nutrients: Having lower levels of vitamin D, vitamin B-6, and vitamin B-12 in one’s body have also been linked to an increased risk of developing the condition.
It is important to note that researchers are still actively studying why MND may develop in some people but not in others.
(Cleveland Clinic, 2025; Emmady, 2022; Mayo Clinic, 2025)
Signs and Symptoms
Symptoms in MND may vary as they can affect people differently depending on what area or part of the brain is affected the most.
Cognitive symptoms of MND may include:
- Having difficulty and trouble saying your thoughts
- Memory loss
- Problems with following directions or remembering steps
- Trouble with reading, writing, or understanding words
Behavioral and psychological symptoms of MND may include:
- Agitation
- Anxiety
- Depression
- Disorientation of where you are or what time it is
- Irritability
- Experiencing hallucinations
- Experiencing paranoia
- Fidgeting or repeating movements
- Sleep problems (constantly waking up at night or sleeping during the day)
(Cleveland Clinic, 2025)
Stages of Dementia
Most doctors describe MND in three stages based on the severity of the symptoms experienced. The three stages of MND consist of early-stage dementia, middle-stage dementia, and late-stage dementia.
In early-stage dementia, an individual’s symptoms are mild and not severe. An individual with early-stage dementia may exhibit some thinking and memory difficulties, but these are not as severe to the point of interfering with their self-care tasks. For instance, they are able to still actively dress themselves, bathe themselves, and plan or make meals for themselves.
In middle-stage dementia, an individual’s symptoms become moderately severe in which their memory, and also their ability to execute daily and self-care tasks become more difficult. Individuals in this stage of dementia may need constant prompts and reminders in order to complete their tasks.
In late-stage dementia, an individual’s symptoms are severely worse. Individuals in this stage of dementia have lost most of their memory and cognitive skills, and will need constant and daily help with caring for themselves. They require full-time support with engaging in basic activities and self-care tasks such as dressing, bathing, and eating meals.
(Cleveland Clinic, 2025)
Diagnosis
In diagnosing MND or dementia, a doctor or provider will generally ask about the signs and symptoms you have experienced and how often you experience them, review personal and family medical history, look at medications you have currently been taking, and order the necessary tests to confirm a diagnosis. In a therapeutic and psychological setting, the evaluation of dementia may also include the use of screening instruments to screen for cognitive impairments. Examples of cognitive screening tests that may be used to screen for dementia include the Mini-Mental State Examination (MMSE) or Montreal Cognitive Assessment (MoCA).
(Cleveland Clinic, 2025; Miller et al., 2024)
The common tests that are used to confirm a diagnosis for dementia consists of mental status exams like cognitive screening tests (e.g., MMSE, MoCA) for memory and thinking, brain scans for structural changes (CT, MRI, PET), blood tests or cerebrospinal fluid tests to assess for other causes, and psychiatric evaluations for mood and behavior (Miller et al., 2024).
Treatment
Currently, there is no cure for MND as research is still undergoing to better understand this condition. However, treatment focuses on managing the symptoms so that it reduces the extent in which the condition interferes with one’s daily functioning and life. Treatment for MND may also vary depending on the individual since this condition can affect people differently. As the condition progresses, some treatments may also become less effective.
Prescribed medications are the first-line of treatment that works for most types of dementia. Common medications consist of:
- Antidepressants and antipsychotics: May help alleviate and manage anxiety, mood swings, and behavioral issues.
- Cholinesterase inhibitors (donepezil, rivastigmine, galantamine): Helps to enhance memory by altering the chemical balance in the brain.
- NMDA receptor antagonist (memantine): Helps regulate brain activity which may promote memory and make daily activities easier to do.
- Anti-amyloid therapies (lecanemab, donanemab): Most helpful in the early stages of Alzheimer’s disease by slowing the progression of the disease and eliminating the amyloid plaques in the brain.
Additional non-medication treatments may also support brain functioning through the following ways:
- Managing and treating health conditions that may affect your brain, like diabetes and blood pressure
- Balancing vitamin, calcium, thyroid or blood sugar levels in your body
- Changing your medication dosage or medication type
- Having surgery in order to reduce pressure in your brain (such as from a tumor)
- Treating infections with medications
- Eating healthy
- Consistent participation in physical exercise
- Being socially engaged
- Engaging in hobbies to challenge thinking skills
Although there is no specific way to prevent dementia, some steps that may be taken to help lessen the risk of developing the condition includes keeping your mind active by taking part in mentally stimulating activities (e.g., reading, solving puzzles), exercising and being physically active, quit smoking, taking care of your physical and mental health, and maintaining a healthy diet.
(Cleveland Clinic, 2025; Emmady, 2022; Mayo Clinic, 2025)
Conclusion
Major neurocognitive disorder (MND), also known as dementia, is characterized by a persistent or progressive loss of functioning in an individual’s memory and cognitive skills, that is most typically pronounced after age 65. MND symptoms are presented differently in people depending on what area of the brain is most affected by this condition. Having Alzheimer’s disease is the most common cause of MND however, there can be multiple causes for this condition typically due to damaged nerve cells or loss of nerve cells and their connections within the brain. If you or a loved one finds it difficult to carry out everyday tasks, or if you see changes in your behavior, memory, or mental functioning, it is important for you to schedule an appointment with a physician or provider to determine a potential diagnosis of MND. While there isn’t a cure for MND, most treatments help reduce its symptoms, and research is still being done to understand more about the condition and find better ways to treat it.
References
Cleveland Clinic. (2025). Dementia: What It Is, Causes, Symptoms, Treatment & Types. Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/9170-dementia
Emmady P. D. (2022). Major Neurocognitive Disorder (Dementia). National Library of Medicine. https://www.ncbi.nlm.nih.gov/books/NBK557444
Mayo Clinic. (2025). Dementia – Symptoms and causes – Mayo Clinic. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/dementia/symptoms-causes/syc-20352013
Miller, M., Ward, M., Keith, C., Patel, V., Haut, M. W., Wilhelmsen, K., Navia, O., Mehta, R., Marano, G., & Kiddy, A. (2024). Managing neurocognitive disorders in the real world: Optimizing collaboration between Primary Care Providers and dementia specialists. The American Journal of Geriatric Psychiatry: Open Science, Education, and Practice, 1, 17–27. https://doi.org/10.1016/j.osep.2024.04.001
