How do we know when someone is looking at us?

What I'm trying to say is hard to put in words, but what I mean is like: when I'm In a public restroom of restaurant bathroom, I feel as if someone's watching me or there's a camera inside (I know I'm a little paranoid). When I'm in my room and I'm alone I feel as someone is stalking me, or sometimes when I'm on my iPhone, I feel as if someone is looking at me through my front-facing camera… If you get where I'm coming from, let me know if you feel this way too, I feel as if I'm the only one going crazy.

One can just feel it

Indeed… We're watching you right now. And we're disgusted. We thought we had chosen wisely… How do you even do that with a flashlight?

We just do. It's a feeling, connected to instinct. But why someone is looking- that's something people tend to jump to wrong conclusions about. Truth is, nobody really knows why except the person looking.

No your just as crazy as me but at least we're alert.

There are several things going when you see someone looking at you, all of which happen very quickly.

(This applies to actually seeing someone looking at you, not "sensing it" from behind or in the periphery.)

The first thing to note is that primates (including humans) are unique in the degree to which the eyeball can move around in the eye socket. This allows visual attention to be shifted quickly without physically moving the head.

Primates and certain other mammals can tell when another animal is looking at them, but humans are particularly good at doing this from a distance. In fact, humans have the added ability to be able to tell where someone is looking, even when it is not at them.

It is easy to see why this skill confers an evolutionary advantage: By being able to do this, you can essentially "read out" the location of another animal'sattention. If you are a social animal, and the one looking at you is a superior, you better behave. Or if it is an inferior, you are being challenged and need to respond so you don't lose your place in the status hierarchy. For humans, knowing where another human is looking allows you to read their mind regarding what they are thinking about. This is invaluable when trying to learn language, since it allows you to pair particular words with particular objects in the environment. Pointing is also effective for this.

So, how do we do it?

Detecting direction of gaze has to do with noticing the relative location of the dark spot of the eye (the pupil and iris) in the context of the whites of the eye. Thedifferential size and location of the white region shows where the eye is pointed. And if the pupil is exactly in the middle with equal white regions on each side, then the eyes are looking at you. We can see this from across the room. Head direction also provides a cue, which is primarily determined by where the region of the two eyes and the nose are relative to oval face region, with hair as another reference marker. When the head is turned, the brain has to do some geometry to determine gaze direction from both head angle and relative eye angle.

Its all in your mind i used to feel like someone was looking at me when i went to public bathrooms. But i don't feel that way anymore your probably just really paranoid just take some breaths or i would suggest getting cancelling and talking about way you feel this way.