Scientists reveal brain works differently during sleep transition

Scientists have revealed that the human brain exhibits a more intricate functioning during the transition into sleep than was previously understood. New research indicates that dream-like visuals and thoughts are not confined to sleep but can manifest even when an individual perceives themselves as awake.

The boundary between sleep and wakefulness is not as clear-cut as commonly assumed. Many people experience peculiar images, fragmented thoughts, and difficult-to-interpret scenes as they drift off to sleep. This state, often described as 'drifting off,' involves the brain shifting to a different mode of operation before fully entering sleep.

A study conducted by researchers at the Paris Brain Institute involved 92 participants to examine this transition phase. Participants were allowed to fall asleep and then awakened at the precise moment of transition. They were then asked to describe their mental experiences just before being woken. This method was inspired by an idea attributed to Thomas Edison, who reportedly woke himself by dropping an object to capture ideas that came to him while dozing.

The research analyzed not only participants' self-reported experiences but also their brain activity through EEG recordings. This allowed researchers to compare subjective feelings with objective brain states. A key finding was that the mental experiences during the sleep transition did not fit into a single category. Some participants reported everyday thoughts, others focused on environmental sounds or bodily sensations, while some maintained more controlled and planned thoughts.

Most notably, the study found that dream-like experiences could occur during wakefulness, as indicated by EEG data, not just in deep sleep. This suggests the brain does not operate in distinct 'awake' or 'asleep' modes. Even when feeling awake, the mind can generate dream-like imagery. Researchers propose that mental experiences might be determined by activity patterns in different brain regions rather than solely by sleep stages, which could explain why some individuals experience logical thoughts even in deeper sleep phases.