A simple reflex or the foundation of our coordination: why do we twitch during sleep?

Watching the sudden movements of pets' paws during sleep, people have long associated these twitches with dreaming. In humans, rapid eye movements (REM) during deep sleep are closely linked to dreaming, and it was believed that similar twitches in animals indicate the same cause. However, the actual roots of this reflex may be quite different and significant for the entire organism, as reported by Vox.

Neurobiologist Mark Blumberg from the University of Iowa questioned this assumption, noting that newborn animals with minimal life experience also exhibit twitches during sleep. He expressed his curiosity on the matter: "Newborn animals have very little waking experience. What on earth are they dreaming about?"

To investigate this, Blumberg conducted experiments on newborn rats, surgically disabling the brain area associated with dream generation. Surprisingly, the twitches remained unchanged, indicating that these movements are not necessarily linked to dreaming.

Blumberg's research suggests that these twitches serve as a mechanism for the developing brain to map and understand bodily movements. Each twitch sends sensory feedback, aiding the brain in learning about the structure and capabilities of the body. This process is especially crucial for young animals when their sensorimotor system is forming.

Sleep twitches, also known as myoclonic jerks, are characteristic not only of humans and pets — birds, reptiles, and even insects experience them as well. Dolphins and some whales twitch only on one side of their body because only half of their brain is active during sleep.

In humans, hypnic jerks, the sudden jolts before falling asleep, are considered a survival mechanism inherited from our tree-dwelling ancestors, preventing them from falling off branches.

Scientists have also found that baby rats twitch more frequently than adults, supporting the idea that these movements help fine-tune motor control during development.

In older animals, although twitches occur less frequently, they may help recalibrate and maintain these systems. This perspective challenges the traditional view that sleep twitches are merely a byproduct of dreaming, emphasizing their vital role in neurological development and maintaining our coordination.

This material is for informational purposes only and does not contain advice that may affect your health. If you are experiencing issues, please consult a specialist.