Infants spend most of their time sleeping. During the first year, the total amount and schedule of sleep usually change several times every day. Smiles, sucking motions, and random movements are all common at this time. Today, we know that sleep is essential to young children's development. Their brain is hard at work while their body is at rest. But do they dream? For decades, scientists have wanted to know if babies dream during sleep.

According to the American Academy of Pediatrics, a baby's sleep has four successive stages:

1. Drowsiness
In this stage, the babies appear sleepy and gradually fall asleep.

2. REM Sleep (active sleep)
This is the Rapid Eye Movement (REM) sleep stage, also known as active sleep, in which a lot of movement occurs, such as eye movements, twitches, irregular (periodic) breathing patterns, sucking motions, and smiles. During REM sleep, the brain makes new neuronal connections and pathways and processes information.

3. Light Sleep
At this stage, the physical movements begin to slow down.

4. Deep Non-REM Sleep (quiet sleep)
During this phase, the babies are very still and calm, their breathing is more regular and deeper, and they are harder to wake up compared to previous stages.

Good sleep is linked to physical growth, cognitive development, and memory formation. On average, newborns sleep around 16-17 hours per day over periods of 3-4 hours. And they spend more time in REM sleep than at any other period in life. After a year, the total daily sleep duration decreases to 13-14 hours, with the longer period occurring, in principle, through the night.

But back to the scientists' question: Do babies dream? Dreaming depends on our ability to produce abstract thoughts and, in particular, distinguish "self" from "not-self." The problem is that babies cannot tell us what happens when they sleep. So far, researchers hypothesize - since current technology can't confirm or refute it yet - that the baby's brain is not mature enough to dream, as this state is generally defined.

Picture: Closeup of a cute baby napping (ChildUp & DALL-E - 2023)