Neurological & Neurodegenerative Conditions

Neurological conditions affect the brain, the spinal cord and the nerves running to the rest of the body. Some are neurodegenerative, meaning nerve cells are gradually lost. Others involve nerves that signal wrongly rather than nerves that die. This page is a way in to the specific conditions.

Conditions in this area

• Alzheimer’s disease: the most common cause of dementia, a specific disease of the brain that gradually affects memory, language and judgement.
• Dementia: the umbrella term for the symptoms Alzheimer’s disease and other brain conditions cause. About 771,939 people in Canada were living with dementia at the start of 2025.
• Memory loss and mild cognitive impairment: memory or thinking below what is expected for your age, while daily life is still manageable. It does not always progress.
• Parkinson’s disease: brain cells that make dopamine are gradually lost, bringing tremor, stiffness, slowness and poor balance. About 111,000 people aged 40 and older in Canada live with parkinsonism.
• Multiple sclerosis: the immune system damages the coating around nerves in the brain, spinal cord and optic nerves. Canada has one of the highest rates in the world, about 90,000 people.
• Trigeminal neuralgia: sudden, brief, electric-shock-like pain in the face, often set off by a breeze or brushing your teeth.
• Peripheral neuropathic pain: burning or shooting pain from damaged nerves in the hands, feet or limbs, often related to diabetes.
• Migraine and headache disorders: attacks of head pain with nausea and sensitivity to light or sound, affecting more than 5 million people in Canada.

What these conditions have in common

They all involve the nervous system, and they are assessed the same way: a careful history, a neurological examination, then imaging or nerve testing only where it changes the answer. Because the nervous system controls everything, a problem in one place shows up as very different symptoms depending on where it sits. Two people with the same diagnosis can look nothing alike.

Several also share risk factors that surprise people. Blood pressure, blood sugar, cholesterol, activity, smoking, untreated hearing loss and head injury all affect brain health, which is why brain and heart care now overlap. Beyond that, the grouping is administrative: migraine and Alzheimer’s disease share this list because a neurologist sees both, not because they are related.

Treatment and management in Canada

For most conditions here, care is aimed at symptoms and at keeping you doing what matters to you. Multiple sclerosis is the exception, with disease-modifying treatment well established. A health care team may discuss:

• Medicines aimed at symptoms, such as dopamine-based treatment in Parkinson’s disease, or preventive and acute migraine medicines
• Disease-modifying therapies, which exist for multiple sclerosis and are newer in Alzheimer’s disease
• Medicines used specifically for nerve pain, which differ from ordinary painkillers
• Physiotherapy, occupational therapy and speech-language therapy
• Support for sleep, mood and thinking, since these change how the main condition feels
• Procedures in selected cases, such as deep brain stimulation or nerve procedures for facial pain
• Care partner support, home care and long-term care as needs change

Several of these decisions are finely balanced. They belong to you and your own clinician, and nothing here is a recommendation about any of them.

When to talk to a doctor

• Sudden weakness or numbness on one side, a drooping face, trouble speaking, sudden loss of vision, or a sudden severe headache unlike any before needs emergency care. Call 911, because these can be signs of stroke and treatment is time-critical.
• A first seizure, or a headache with fever and a stiff neck, needs emergency care.
• Spreading weakness or numbness, or new loss of bladder or bowel control, needs same-day assessment.
• New confusion, or a change in memory or behaviour over weeks rather than years, should be assessed promptly.
• Memory changes that worry you or your family are worth an appointment, since some causes can be treated.

Why research in this area matters

For most conditions in this group, nothing available today stops the underlying process. Multiple sclerosis care has changed considerably over three decades of research, which shows what is possible. Alzheimer’s disease and Parkinson’s disease are earlier in that arc: treatments aimed at the biology rather than the symptoms are now in trials, as are ways of finding these diseases years before symptoms appear. Nerve pain research is looking for options that are not opioids.

Studies are how any of this is tested, and they often need people at a specific stage. Taking part is voluntary, you give informed consent first, and you can withdraw at any time without affecting your regular care. No one can tell in advance whether a study will help you personally.

Learn more from Canadian sources

• Alzheimer Society of Canada
• Parkinson Canada
• MS Canada
• Migraine Canada
• Public Health Agency of Canada: neurological conditions