Sleep studies have shown that people who have trouble sleeping tend to think they’re awake more than in actuality. Even for those without sleep problems often don’t remember being asleep, so that time flies in comparison to time awake.

Paradoxically, we also experience thoughts and dreams in Light sleep, and these thoughts can carry on the same emotional tone as worrisome thoughts we had before falling asleep. The boundary of sleep is not as distinct as it’s made out to be, and some poor sleepers worry about not being asleep even when they are.

The good news is that people with insomnia actually improved their assessment of time awake at night when shown data from a sleep sensor.

Of course, it’s possible to get a lot of sleep but still spend plenty of time tossing and turning in bed. When there’s a high Light sleep value, but not much Deep sleep or REM, what’s likely going on is sleep fragmentation. Fragmentation is poor quality sleep in which frequent awakenings actually prevent the brain from cycling into the other stages of sleep.

More importantly, sleep fragmentation can be a sign that you are being interrupted by noises or lights at night, or even a more troubling sign of a sleep disorder or mental health issue.

It’s best to look into what’s causing the bouts of wakefulness in the middle of the night and to help you make future changes. Keeping a journal nearby to jot down your experiences can be helpful in spotting patterns or behaviors and then taking the next steps.