A hypnagogic jerk is best defined as a muscle spasm occurring during which sleep transition?

A hypnagogic jerk is best defined as a muscle spasm occurring during which sleep transition?

• A. From stage 1 to stage 2 sleep
• B. From stage 2 to REM sleep
• C. From sleep to wakefulness
• D. From wakefulness to sleep

Answer: (D)

A hypnagogic jerk occurs at sleep onset, when you are transitioning from wakefulness into sleep. As you drift from being awake into the first stages of non-REM sleep, a sudden muscle contraction can occur, sometimes with a sensation of falling. This is a common, benign phenomenon and specifically tied to the wake-to-sleep transition. It is not related to moving between stages after sleep has started (such as from stage 1 to stage 2 or into REM), nor to waking up (hypnopompic jerks involve waking transitions).

A hypnagogic jerk occurs at sleep onset, when you are transitioning from wakefulness into sleep. As you drift from being awake into the first stages of non-REM sleep, a sudden muscle contraction can occur, sometimes with a sensation of falling. This is a common, benign phenomenon and specifically tied to the wake-to-sleep transition. It is not related to moving between stages after sleep has started (such as from stage 1 to stage 2 or into REM), nor to waking up (hypnopompic jerks involve waking transitions).