When muscular contractions not repressible by voluntary control appear at the moment of entering the dream, which are characterized by being brief, rapid and unexpected, and which sometimes affect the whole body and produce a sensation of falling into emptiness or stumbling, we speak of numbness myoclonus .
If the muscle jerk is massive and abrupt, it can even wake us up. Experts estimate that this physiological phenomenon affects 7 out of 10 people at some point in their life . It always occurs before the phases of superficial sleep, deep sleep and REM, which are repeated cyclically throughout the night.
