Adrenaline increases the "alertness" of the nervous system, meaning it's ready to trigger muscle contraction. It also increases the amount of blood flow and changes the tension of the muscles, which, ...

Infectious agents can cause muscle twitching and spasms, too. The most commonly known is probably tetanus, which causes a phenomenon called lockjaw, where the neck and jaw muscles contract to the ...

Add Yahoo as a preferred source to see more of our stories on Google. Tweaked by a muscle twitch? From an uncontrollable fluttering eyelid to a pulsing calf muscle, these small, rapid involuntary ...

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Medically reviewed by Nicholas R. Metrus, MDMedically reviewed by Nicholas R. Metrus, MD Almost all of us will have experienced a fasciculation at one time or another. A fasciculation is simply a ...

You’re a real jerk if you do this in bed — literally. A Maryland doctor is sharing why people often twitch or experience the sensation that they’re falling just before they fall asleep. Taking to ...

Ever sit in a chair and feel twitching in your eye? Or maybe your calf muscle. You may suffer from benign fasciculation syndrome. Dr. Jerry Fleishman of Medstar Franklin Square Medical Center talks ...

Have you ever experienced an annoying, persistent twitch in your eyelid? Eye twitching — also known as myokymia — is a common phenomenon that most people encounter at some point in their lives. While ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. Credit: Getty Images It tends to happen when you’re just about to drift off where your legs or ...

Sitting at your desk, a muscle in your leg palpitates quickly. Or a muscle under your eye flutters. These sudden twitches, known as fasciculation, occur commonly and seem random. But are these spasms ...

Hemifacial spasms happen when a blood vessel puts excess pressure on a facial nerve, per the National Institute of Neurological Disorders and Stroke (NINDS). They can also be caused by external nerve ...