私にも経験がありますが、数日前に家内が夜中に足がつったと大騒ぎしたばかりなので "Facts, Answers to Life's little Mysteries, What are those twitches and jerks that occasionary wake us just as we are falling asleep?" と題したリーダーズダイジェスト４月号の記事が目に留まりました。 その中の一節です。
You have been a victim of what is called a 'hypnic jerk, ' a phenomenon explained in David Bodanis's The Body Book: "They occur when nerve fibres leading to the leg, in a bundle nearly as thick as a pencil, suddenly fire in unison.
（中略）
Although some people experience them more often than others, their appearance is unpredictable, unlike myoclonic jerks - spasms that occur at regular intervals during deep sleep.
家内を襲ったのは "hypnic jerk" ですが、辞書では何と説明しているか見ます。
MedTerms Medical Dictionary
Hypnic jerk: The common normal phenomenon of jerking awake, usually accompanied by a feeling of falling, just as one is drifting off to sleep. Also called a sleep jerk or sleep start.
"myoclonic jerks" も辞書を引きます。
Dictionary of Cancer Terms: A sudden, brief, strong contraction of a muscle or group of muscles that cannot be controlled.
The American Heritage Dictionary of the English Language
myoclonus: A sudden twitching of muscles or parts of muscles, without any rhythm or pattern, occurring in various brain disorders.
後者の辞書による "myoclonic jerks" の説明はリーダーズダイジェストの記事の説明と違うので困りますが深追いは止めときます。 「足がつる」は "I got a cramp in my leg and couldn't walk." と何かの本に書いてありましたが、"jerk"、"cramp"、"twitch" は似たような意味を持つ単語のようです。 今日はとりあえず "hypnic jerk" だけ覚えることにします。
You have been a victim of what is called a 'hypnic jerk, ' a phenomenon explained in David Bodanis's The Body Book: "They occur when nerve fibres leading to the leg, in a bundle nearly as thick as a pencil, suddenly fire in unison.
（中略）
Although some people experience them more often than others, their appearance is unpredictable, unlike myoclonic jerks - spasms that occur at regular intervals during deep sleep.
家内を襲ったのは "hypnic jerk" ですが、辞書では何と説明しているか見ます。
MedTerms Medical Dictionary
Hypnic jerk: The common normal phenomenon of jerking awake, usually accompanied by a feeling of falling, just as one is drifting off to sleep. Also called a sleep jerk or sleep start.
"myoclonic jerks" も辞書を引きます。
Dictionary of Cancer Terms: A sudden, brief, strong contraction of a muscle or group of muscles that cannot be controlled.
The American Heritage Dictionary of the English Language
myoclonus: A sudden twitching of muscles or parts of muscles, without any rhythm or pattern, occurring in various brain disorders.
後者の辞書による "myoclonic jerks" の説明はリーダーズダイジェストの記事の説明と違うので困りますが深追いは止めときます。 「足がつる」は "I got a cramp in my leg and couldn't walk." と何かの本に書いてありましたが、"jerk"、"cramp"、"twitch" は似たような意味を持つ単語のようです。 今日はとりあえず "hypnic jerk" だけ覚えることにします。
トータル
