Understanding Neurological Disorders

Neurological disorders are diseases of the central and peripheral nervous system. In other words, the brain, spinal cord, nerves and muscles, which regulates and coordinates body activities.

Dementia is a progressive degeneration of the brain and its ability to function. It is an extremely serious condition that changes a person’s personality and affects their ability to go about their daily life. Dementia mostly occurs in the elderly.


People with dementia suffer from worsening memory, particularly in relation to new information. At first, they may notice things like losing their keys more often, but as the disease progresses they may no longer recognize their own family members. They also worsen in their ability to make judgements, to manage their affairs, and to plan things. People with dementia lose social skills, and often have problems controlling their mood, with a tendency to become irritable or agitated. The symptoms typically emerge and worsen over a period of years.


There are a number of different causes of dementia, of which the most common is Alzheimer’s disease, linked with the build-up of abnormal ‘amyloid plaques’ and ‘tau tangles’ in the brain. Certain other types of dementia also have an abnormal build-up of tau protein in the brain; as a group, these are termed ‘tauopathies’.


People with dementia will ultimately become completely dependent on a caregiver. However, a limited number of symptomatic treatments are available that can improve a person’s functioning and quality of life, particularly in earlier stages of the disease.


Get a deeper understanding of Alzheimer's disease here.

Epilepsy is a brain disorder in which people experience ‘seizures’ – sudden surges of electrical activity in the brain. During a seizure, most people will experience changes in awareness and how they sense things, from ‘spacing out’ to completely losing consciousness. Physical symptoms are common, including difficulty talking, tremors, and convulsions. Some seizures have mild symptoms and may initially be hard to notice, whereas others are completely disabling. Depending on the type, a seizure can last from a few seconds to several minutes.


There are many known causes of seizure, such as inherited conditions and brain injuries, though in most cases no cause can be identified. There are also different types of epilepsy ‘syndrome’ – groups of features that occur together. Lennox–Gastaut syndrome is a rare but severe type of epilepsy that emerges during childhood. The person’s seizures cause them to stiffen or go limp, and they will require lifelong treatment. Dravet syndrome is a rare, inherited type of epilepsy that typically starts within the first year of life. Seizures can be triggered by a fever, or even by a slight change in body temperature.


Epilepsy is a disabling condition that can affect a person’s safety as well as their ability to function at work or school. For example, people with epilepsy are at high risk of having a traffic accident, and in most cases they should not drive. In some people who experience repeated, severe or prolonged seizures, epilepsy can cause damage to the brain.

Get a deeper understanding of Lennox–Gastaut syndrome here.

Movement disorders are associated with abnormal and involuntary movements. Broadly, movement disorders can be split into those where the affected person moves too much (e.g., Tourette’s syndrome or Huntington’s disease), and those where the affected person moves too little (e.g., Parkinson’s disease or multiple system atrophy).


Tourette’s syndrome is associated with involuntary, repetitive movements or vocal sounds, known as ‘tics’, which emerge during childhood. Huntington’s disease is an inherited, progressive brain disease that usually emerges during middle age. It causes involuntary jerky movements of the body, known as ‘chorea’, as well as problems with thinking and memory, and changes in behavior and personality.


Parkinson’s disease is a long-term and progressive brain disease that mostly occurs in the elderly. It causes tremor, slowness of movement, stiffness, and balance problems, as well as a large group of symptoms that are not related to movement (e.g., pain, mental health issues, and problems with thinking and memory). Multiple system atrophy has similar movement symptoms to Parkinson’s disease, but it is rarer, progresses more rapidly, is harder to diagnose, and has fewer treatment options.


Movement disorders are a source of stigma and can interfere with an individual’s ability to function in daily life. Whereas Tourette’s syndrome may improve with age, people with a progressive brain disease will ultimately become completely dependent on a caregiver.


Get a deeper understanding of Tourette’s syndrome here and Parkinson’s disease here.

Pain is an unpleasant sensation that can occur acutely (e.g., after bruising or breaking a bone) or chronically (e.g., after a back injury or stroke). Sometimes, there is no obvious cause of pain. Different people experience pain in different ways, and there is also an emotional component, whereby the pain that is felt changes according to a person’s mood.


Whereas acute pain is the body’s way of warning us about damage, chronic pain has no use and arises due to a malfunction of the body’s pain system. Neuropathic pain is an example of chronic pain, caused by damage to nerve cells by injury, poison, or as a consequence of some other disorder. Neuropathic pain can be excruciating, affecting a person’s quality of life, mood, sleep, relationships, and ability to work.


Headache is pain that occurs in the head. Headaches are extremely common, and can be ‘primary’, such as migraine, tension-type headache and cluster headache, or ‘secondary’, meaning that they are a consequence of another disorder. Migraine is associated with strong headaches that are usually accompanied by nausea and/or sensitivity to light and sound. During a migraine headache, which last for hours or days, a person is unable to go about their daily life. Tension-type headaches are, in general, milder and not associated with nausea while cluster headaches are a relatively rare and extremely painful type of headache usually felt around a person’s eye or temple.


Get a deeper understanding of neuropathic pain here and migraine here.

People with sleep disorders have unsatisfactory sleep, whether in terms of the quality, timing, or the amount of sleep they are getting. As a consequence, they feel sleepy during the day, suffer from stress, have mood disturbances (e.g., irritability and exaggerated emotions), and struggle to carry out normal daily activities, such as being productive at work or at school.


There are many types of sleep disorder, some of which are relatively common (such as insomnia, sleepwalking, and breathing disorders in the elderly), and others of which are quite rare (such as narcolepsy). Sleep disorders are often accompanied by depression, anxiety, and changes in a person’s ability to think. In many cases, sleep disorders are a sign or consequence of some other medical condition or mental disorder. For example, excessive daytime sleepiness is a common symptom of degenerative brain disorders such as Parkinson’s or Alzheimer’s disease.


Narcolepsy is a particularly burdensome sleep disorder. People with narcolepsy are excessively sleepy during the day and need regular naps. Many people with the disorder also experience sudden muscle weakness, which can make them fall over. Not only does narcolepsy affect work performance and relationships, but activities such as driving become much more dangerous.


Get a deeper understanding of narcolepsy here.

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