How Is It That We Can Tell That We’re Being Watched?

by | Aug 21, 2020


Have you ever had the sensation that you were being watched, then looked around and in fact saw someone watching you? What’s going on? Do we have a sixth sense (or a seventh sense if you can also see dead people)?

It’s a pretty common phenomenon and it’s not a sixth sense. The reasons why we can sometimes tell we are being watched are fascinating.

The Power of the Subconscious

The primary reason why we can tell when we are being watched is that our subconscious can pick up on cues that conscious mind is not aware of. Our subconscious picks up on gazes in the perifery of our vision or in reflections which aren’t noted by our conscious minds.

In his fantastic book The Power of Fifty Bits Bob Nease explains that “each second, your brain devours about ten million bits of information [but] the conscious part of your brain can only process about fifty bits per second.” This is a HUGE gap in processing power and means that “99.9995 percent of our bandwidth is beyond the reach of our awareness.”

This huge awareness gap means that our subconscious knows about many things going on around us that do not register with our conscious mind. When the subconscious awareness of being watched bubbles up into our conscious thought it feels like we used some sort of extrasensory perception. But that isn’t the case. Experiments have found that we can’t actually tell whether we’re being watched when the watcher is outside our field of vision. So, we don’t actually have eyes in the back of our heads!

The Power of Eye Gazes

Our conscious and subconscious minds are primed by evolution to notice the gazes of others. Making eye contact is a key aspect of human social interaction and is an important aspect of how we communicate. Research has found that the human brain is highly attentive to the gaze of others and suggests that there is a neural network in our brains dedicated to processing eye contact. Moreover, infants have been found to be very aware of whether eye contact is being made with them or not and lack of eye contact in babies is an early sign of autism.

Another interesting related fact is that the human eye is also formed in a way to communicate where we are looking. Unique among almost all other species, humans have a great deal of white (the sclera) around our pupils which is visible. The large and visible whites of our eyes make it very easy to discern the focus of someone’s gaze. Other animals, especially predators, have little or no sclera showing which acts to camouflage from their prey where they are looking.  Here’s a related IFOD that is super interesting about predator vs. prey eye placement: Stereo Vision. Finally, check out this collage of various eyes and note how only the human eyes have a visible sclera.



  1. One note from the training/biology field is when working with either predators or prey, you do not want to look them directly in the eye as it can be perceived as, respectively, a challenge or a threat. It is a very difficult thing to remember, if for example you are holding an eagle on your arm and their face is level with yours. The human tendency is to engage with the eyes and face. Interesting evolutionary adaptation— may be because our other senses like smell and eyesight are poorer, so having extra white to indicate direction of gaze might be helpful while pack hunting on the plains.

    P.S. dolphins were one of the few animals with which I worked that were willing to look at you and be comfortable having you look at them. With no sclera, tilts of the head were their telltale. But they are a most curious species and are always looking for interesting things in their environment. If you did see sclera, then usually something was up.

    • That is fascinating. Thx.

  2. This post is fascinating.

    Today’s most powerful supercomputer, Summit, at Oakridge National Laboratory, operates at 200 petaflops. A petaFLOP is 10^15 (a million billion) floating-point instructions per second. Summit consumes 13 mega-watts of power to achieve this feat.

    Based on the number of neurons and their estimated average interconnectivity, the human brain operates at one exaFLOP, which is 10^18 (one billion billion) operations per second. The brain consumes about 100 watts; that’s about 130 million times more energy-efficient than Summit.

    Processing power is not the same as bandwidth, the number of bits that are input to a system. Still, the 50 bps estimate of conscious processing bandwidth comes from measuring the entropy of reaction time distributions that provide a lower bound to the processing performed during a single cognitive task (response to a stimulus).

    At any given moment, we can be consciously aware of the objects in our visual field, sounds and voices, the feel of the desk and air currents, the smell of coffee and toast, and perfume wafting through the room, our intentional efforts to think, and emotions that arise.

    A good experiment is to stand outside on a rainy day and note everything that comes into awareness, free of thinking (possibly the slowest faculty we have).

    The 11 Mbps bandwidth estimate for human subconscious processing may also be a lower bound. It would be interesting to hear from a Zen master with knowledge of Shannon’s mathematical theory of communication.

    • Very interesting. Thank you.

    • Yep, the 50 bits per second figure is squishy. The conclusion, however, ain’t: we cannot possibly attend to all of the possible decisions we face all of the time. As a result, evolution has endowed us with shortcuts that, on average and over a long time frame, were better than stopping and “running the numbers.” For better or worse, those short cuts often fall short in today’s environment. That’s because our environment has and is changing far more rapidly than evolution can change our “wet ware.” As a result, if we want to improve our behaviors, it’s often far more effective to change our environments to leverage our existing wiring than to attempt to change our wiring head on. There are multiple examples that attest to the power of this approach.


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