That sense of "being watched"--how realistic is it in a mystery?

Anthony van Dyck - Paris : Gallimard, 1998.

Have you ever had that creepy feeling of being watched?  

And then, when you look around,  someone really is staring at you?  

A strange sensation to be sure.  Certainly, this eerie sixth sense is a staple of crime fiction, especially novels of suspense.  

I was thinking about this recently because I read a mystery where the protagonist just knew she was being watched by someone behind her.  It actually pulled me out of the story a little bit because I started to wonder about how plausible that sensation actually is. There was no other indication that someone was behind her, except that she sensed him looking at her.

So I began to explore this question, and it turns out there's been some research on: (1) whether people can truly sense when someone is staring at them, and (2) whether they can know when someone is staring at them from behind. (Of course some of these explanations are a little more scientific than others).


So, on the more scientific end, there is a phenomenon known as gaze detection. Even from a peripheral angle, the brain is always perceiving the positions of other people's heads and bodies and their relative positions to us. The brain will note anomalies, causing us to become alert (or get that chilly sensation). For example, your brain may take note that there is a woman near you who has her feet pointed away from you, but that her head is faced in your direction.  Your brain might note this unusual positioning and tip you off, because it is wired to let you know when you are danger.

Apparently, gaze detection also suggests that we may be able to note the whites of another person's eyes even at a distance, so we can perceive when someone is looking at us. So, gaze detection may help explain this phenomenon of being watched. 

However, gaze detection can only account for someone who is staring at us from our periphery.  It can not explain someone staring at us from behind.  

So a more popular explanation is the idea of morphic resonance,   which contends that: "Natural systems, such as termite colonies, or pigeons, or orchid plants, or insulin molecules, inherit a collective memory from all previous things of their kind, however far away they were and however long ago they existed," Sheldrake (1988) (as quoted by Michael Shermer)

Say what?

I think Sheldrake means that there is a kind of telepathic vibration among organisms, which seems to somehow explain how people "know" someone is staring at them. This concept is critically examined by Scientific American and discussed by Morgan Freeman in Through the Wormhole. Not sure I buy this one, but it's certainly imaginitive.

Personally, I think it's more likely that when you get that weird feeling, and you turn around, that the person beside you notices you turn around and ends up meeting your eyes, hence looking like he or she was staring. 

 So, since my mysteries are not supernatural in nature, I wanted to make sure that I had a logical and plausible explanation for any such feelings of super-awareness that I mention in my characters.  Did my character spy something out of the ordinary? Was there a movement at the corner of her eye? Did she hear a twig snap, alerting her on some level that someone was behind her?

But what do you think?  Is a little sixth sense okay, or should there be a logical explanation for such feelings? 

And yes, I am looking at you...