Sleep inertia is the result of sudden awakening during REM sleep. When you wake up during REM, you still have high levels of melatonin, causing sleepiness. The longer you sleep, the higher level of melatonin is observed during REM stage.

N1 (Stage 1) – The lightest stage of sleep, when you are between being awake and asleep. N2 (Stage 2) – When you fall more soundly asleep, and become unaware of your surroundings.

We spend the most time in deep sleep during the first half of the night. During the early sleep cycles, N3 stages commonly last for 20-40 minutes.

Tips for better sleep

1. Put yourself on a bedtime schedule where you go to sleep and wake up at the same time each day.
2. Get plenty of exercise.
3. Stick to water and other decaffeinated drinks before bed.
4. Create a bedtime routine to unwind from the day, like reading a book or taking a bath.

It doesn’t make you sleep, but as melatonin levels rise in the evening it puts you into a state of quiet wakefulness that helps promote sleep,” explains Johns Hopkins sleep expert Luis F.

As the night progresses, the REM episodes get longer and the non-Rem periods in-between become shorter (thus still adding up to 90 minutes) as well as shallower. Thus, the really deep sleep (e.g, Stage 3) occurs only during first 1-2 cycles early in the night.

If you wake up at 3 a.m. or another time and can’t fall right back asleep, it may be for several reasons. These include lighter sleep cycles, stress, or underlying health conditions. Your 3 a.m. awakenings may occur infrequently and be nothing serious, but regular nights like this could be a sign of insomnia.

Gaze-Detection System We’re able to easily discern where someone is looking. This system is especially sensitive when someone is looking at you directly, and studies have found that particular cells fire when this happens.

Help the person to become aware of their staring Look back, smile and hold the other person’s gaze briefly. Most people will smile back and then look away. Look back, smile or nod to show them you have noticed – this may also break the ice.

Specifically, this study showed that we can detect that people are looking at us within our field of view – perhaps in the corner of our eye – even if we haven’t consciously noticed. It shows the brain basis for that subtle feeling that tells us we are being watched.

A feeling of a person or agency, without being heard or seen. It is a felt presence, one of the most unusual experiences a person can have, and yet also a feeling that will be familiar to many.

Feeling of Presence, or FoP, is the disconcerting notion that someone else is hovering nearby, walking alongside you or even touching you. It’s the stuff of ghost stories, but also a real symptom of several neurologic conditions, including schizophrenia and Alzheimer’s disease.

The psychic staring effect (sometimes called scopaesthesia) is a supposed phenomenon in which humans detect being stared at by extrasensory means.

Being touched as created by your mind is called tactile hallucinations. It isn’t the most common hallucination, but it is a real thing and feels really real. In the beginning it felt so real that I fought myself off from believing there was a real person doing all of this that is somehow invisible!