A loss of feeling.
Partial or total lack of sensation in a part of the body, often accompanied by tingling. Minor nerve damage or more serious nerve injury or dysfunction may cause it.
Partial or total loss of sensation in part of the body that is caused by interference with the passage of impulses along sensory nerves. Numbness suggests that the affected nerve is damaged. It is a more serious condition than tingling or a pins and needles sensation, which suggest that a nerve is compressed but not damaged. Possible causes of numbness include nerve injury; lack of blood supply; diabetes mellitus, type 1 and type 2; thyroid problems; vitamin B12 (cyanocobalamin) deficiency; carpal tunnel syndrome; transient ischemic attack; stroke; and multiple sclerosis.
A reduction in feeling in a body region due to disruptions in the transmission of signals along sensory nerves.
Numbness can arise from natural causes, like when sitting cross-legged temporarily restricts blood flow to a leg nerve. It can also be intentionally induced, as when a dentist uses anesthesia before filling a tooth. Additionally, it might stem from issues with the nervous system or its blood circulation.
Multiple sclerosis can lead to numbness in various body parts due to harm to the nerve pathways in the central nervous system (CNS). With neuropathy, it’s the peripheral nerves (those outside the CNS) that get damaged. During a stroke, either pressure on or a decrease in blood flow to the brain’s nerve pathways frequently results in a loss of sensation on one side of the body.
Intense cold, like in the case of frostbite, leads to numbness by directly affecting the nerves. Numbness is also a sign of Raynaud’s disease, a condition where the small arteries that provide blood to the nerves in fingers and toes constrict rapidly upon exposure to cold.
Numbness can be a sign of psychological conditions, including anxiety, panic attacks, or conversion disorder.
Typically, an examination identifies an area with decreased or altered sensation that matches the skin area served by a specific peripheral nerve, multiple nerves, or a sensory region in the CNS. The extent and location of this affected area can provide clues about where and how the nerve damage occurred. The approach to treatment is determined by the underlying cause.