A neurological disorder is any disorder of the nervous system. Structural, biochemical, or electrical abnormalities in the brain, spinal cord, or other nerves can result in a range of symptoms. Examples of symptoms include paralysis, muscle weakness, poor coordination, loss of sensation, seizures, confusion, pain, and altered levels of consciousness. There are many recognized neurological disorders, some relatively common, but many rare. They may be assessed by neurological examination and studied and treated by specialists in neurology and clinical neuropsychology.
Causes
Although the brain and spinal cord are surrounded by tough membranes, enclosed in the bones of the skull and spinal vertebrae, and chemically isolated by the blood–brain barrier, they are very susceptible if compromised. Nerves tend to lie deep under the skin but can still become exposed to damage. Individual neurons, the neural circuits, and the nerves into which they form are susceptible to electrochemical and structural disruption. Neuroregeneration may occur in the peripheral nervous system and thus overcome or work around injuries to some extent, but it is thought to be rare in the brain and spinal cord.
The specific causes of neurological problems vary but can include genetic disorders, congenital abnormalities or disorders, infections, lifestyle or environmental health problems including malnutrition, brain damage, spinal cord injury, nerve injury, or gluten sensitivity (with or without intestinal damage or digestive symptoms). Metal poisoning, where metals accumulate in the human body and disrupt biological processes, has been reported to induce neurological problems, at least in the case of lead. The neurological problem may start in another body system that interacts with the nervous system. For example, the cerebrovascular disease involves brain injury due to problems with the blood vessels (cardiovascular system) supplying the brain; autoimmune disorders involve damage caused by the body's own immune system; lysosomal storage diseases such as Niemann–Pick disease can lead to neurological deterioration. The National Institute for Health and Care Excellence recommends considering the evaluation of an underlying coeliac disease in people with unexplained neurological symptoms, particularly peripheral neuropathy or ataxia.