What term describes the feeling of being unable to move during the transition to sleep?

The term that describes the feeling of being unable to move during the transition to sleep is sleep paralysis. This phenomenon occurs when a person is falling asleep or waking up and finds themselves temporarily unable to move or speak. It is often accompanied by a feeling of pressure on the chest and can sometimes include hallucinations.

Sleep paralysis occurs during the transitions between wakefulness and sleep, particularly when entering REM (Rapid Eye Movement) sleep, which is the stage associated with vivid dreaming. During REM sleep, the body experiences a natural paralysis of most voluntary muscles, which is believed to prevent individuals from acting out their dreams. However, if someone becomes aware before this paralysis has entirely subsided, they may feel alert but unable to move, leading to the characteristic experiences of sleep paralysis.

Hypnagogic sensations refer to experiences such as auditory or visual hallucinations that can occur while falling asleep, but they do not specifically describe the inability to move. Lucid dreaming involves awareness of the dream state and often the ability to control the dream narrative, while night terrors are a type of sleep disorder that occurs during non-REM sleep and are characterized by intense fear and agitation, not paralysis.