Gorilla’s In Our Midst

Imagine you are looking at a one-minute video of two teams of people moving around and passing basketballs. One team is wearing white shirts and the other black. You have been asked to count the number of passes made by the players wearing white while ignoring any passes by the players wearing black. You are to include both aerial passes and bounce passes in your final count. Halfway through the video, a young woman wearing a full-body gorilla suit walks into the scene, stops in the middle of the players, faces the camera, thumps her chest and then walks off, having spent about nine seconds onscreen.

Now, do you think you would have seen the gorilla?

Not surprisingly, more than 75% of those who were queried could not imagine missing something as remarkable as a person in a gorilla suit. Nevertheless, as reported by noted psychologists Christopher Chabris and Daniel Simons, who devised this now classic experiment, roughly half of the subjects do not see the gorilla!

I admit, when I first heard about this — at a professional lecture by a famous psychologist — I could not help but be impressed. Here, it seemed, was a truly mind-boggling, profoundly counterintuitive result — or was it? After thinking this over for just a moment, my skeptical instinct, as is my wont, had kicked in. Wasn’t I long familiar with the way seemingly unbiased experiments could inadvertently influence and sometimes produce the very phenomena they were presumably merely impartially observing? Could this be one more example of what happens when the critical psychodynamic factor — in this case the undeniably unique experimental design — is conveniently ignored?

Two months later I would receive a second crack at the celebrated gorilla video. Or rather the nifty computerized version as demonstrated by yet another equally enthused, prominent psychologist. Here against a white background was a simple square, filled with rapidly moving, randomly colliding (like excited molecules), circular objects. Your assignment (should you decide to take it) was, over a one-minute stretch, to count the number of times the circular objects would bounce off the far edges of the square while ignoring all other internal collisions. Almost immediately I found my competitive instincts — aroused by the game-like challenge — devising a makeshift strategy. I would ignore everything occurring directly in front of me and keep my eyes fixated on the four sides of the box. The brunt of the obstacles thereby removed, the way would be open for a more accurate estimate of how many times the tiny circular objects had bounced off the box’s perimeter.

Like everyone else, I would only learn the true purpose of this experiment after it was over. That is, after I had been deceived (if only benignly so, if only as Dan Ariely charmingly put it, “for the sake of science”). For no sooner had I finished my tally than I would realize that the game per se had been a ruse to divert my attention.

“Now, how many of you saw the red crosses marching across the box?” asked the psychologist.

“What red crosses?” Like most of the audience, I had seen only diminutive bouncing ball-like objects.

“Now watch the video again.”

Chance favors the prepared mind, as the saying goes. Alerted to the presence of apparently stealthy, marching red crosses, I realigned my perspective and focused on the center of the box. Incredibly, a tiny, orderly file of red crosses, now impossible to miss, moved ant-like across the page.

I don’t like to be tricked, but I had to smile. The effect is as though a magician had waved his hand and a marching file of red crosses had suddenly materialized. We do not understand how the red crosses got there, or rather, we do not understand how we could have possibly missed them in the first place. So it seems magical, a wonderful magicianly feat — an optical illusion that we did not expect, had never heard of, has just been demonstrated before my very eyes. We laugh at ourselves in the same way we laugh when we realize an ingenious (but acceptable) prank has just been played on us.

If laughter was my first response, skepticism was my second. After all, I immediately asked myself, aren’t the supposed experimental results predicated upon the fact the subjects are first manipulated into looking at the edges and not the center of the box? Is it then so surprising they would tend not to see something they had been implicitly influenced to overlook? Viewed that way, what is truly ingenious about the experiment is how clearly and dramatically it demonstrates just what it is we’re not looking at, or don’t see. And since we almost never see what we miss, it has an undeniable shock effect (analogous to what the magician does when he seemingly produces a solid object out of thin air).

Two months later, I would have an opportunity to see the real thing. In the midst of a lecture by Richard Dawkins at the 92nd Street Y — to promote his latest bestseller, The Greatest Show on Earth — the moderator unexpectedly introduced the gorilla video in the discussion. The point being, as I remember, that you should not always believe what you see, or don’t see. Knowing beforehand the illusion about to be created, I primed myself to see if I could catch red-handed any hint of perceptual deception.

Yet, what I saw could not have been more innocuous or banal. Two teams of college-age students, moving in a circle and passing a basketball back and forth, occasionally throwing in a bounce pass. The players, however, upon closer inspection, do not really seem athletic or interested in what they are doing. They are far more convincing as students participating in a classroom project than as youthful, wannabe basketball players who are honing their skills. Almost halfway through the video, from the far right, a young girl in a full-body gorilla suit saunters into the center of the slowly moving circle. She pauses, nonchalantly but boldly stares into the camera, pounds her chest and then, about nine seconds later, strolls away.

Well, what does one make of this? My very first reaction is that the girl in the gorilla suit looks exactly like a girl in a gorilla suit. That is, she does not look like a gorilla. There is nothing remotely animalistic or terrifying about her. If anything she is faintly comical, as though she is already celebrating the hoax she is about to perpetrate. Not only is she hardly the disruptive presence one might imagine her to be, but as she shuffles through the group of never stationary players, she is, I can also see, rather hard to pick out.

So difficult that not a single player shows any sign of noticing her. And then it hit me! What had been perfectly obvious from the start, so obvious that there had never been a need to address it — was that the six players were, of course, stooges. Each of them instructed to act to the best of their ability as though the girl in the full-body gorilla suit — the girl who supposedly out of the blue had invaded their presence in the most intrusively unimaginable sort of way — was in effect completely invisible to them: fittingly, the title of Chabris and Simons’ book, devoted to the history of their most famous experiment is The Invisible Gorilla. It would be this simple realization that would change everything for me. Much would follow from it. If the six players were playing a carefully scripted role, if the girl in the gorilla suit was only brushing up on her acting while earning a course credit, if the instruction to count the aerial and bounce passes made by the team in white was a ruse, then nothing about this video seems real.

To see this, here is a simple thought experiment. Imagine, for a moment, what it would be like if the gorilla video depicted — instead of being part of a cunningly devised experiment — had in actuality been a real-life video that someone, unbeknownst to you, had managed to capture. Imagine yourself transported back to a time when you might have been engaged in such carefree youthful play. Instead of being a student engaged in a film project, you are actually throwing the basketball around with your friends, doing something that occurs hundreds of thousands of times daily in the playgrounds and gymnasiums of America.

It immediately becomes apparent –once someone imagines the video as a slice of life and not a one-minute experimental playlet — that everything is different. In the real world, for example, each player would have some kind of relationship with every other layer. There would have to be a certain awareness of the faces, the expressions, the bodily movements of their fellow plays as well as the flight of the basketball. No doubt many other things would be on the player’s mind beside the literal counting of passes. In fact, the precise number of passes caught by the white team may well be one of the least important things, one of the last things anyone in the real world would worry about.

Now picture, from this humdrum real life perspective, the arrival of the girl in the gorilla suit, a startling occurrence of which there had been no forewarning. In such a context, it would be hardly possible not to almost immediately notice the girl in the gorilla suit, not to instinctively realize that something outlandishly inappropriate, almost surreal, possibly dangerous, had just occurred. But what? Is the person in the suit a friendly clown, a wise guy, or possibly someone who is seriously deranged? What is on their mind? In such a real life scenario, nothing would be more natural than to nervously look at your friends’ faces to gauge their reactions. Nothing would be less important in this baffling change of contexts than to continue to throw the ball around. And nothing would seem more urgent than to wring from the person in the gorilla suit the explanation for their bizarre interruption. In this real life scenario it would take a truly monumental distraction not to notice the figure in the gorilla suit.

But this is exactly what Simons and Chabris have given us: a powerful if covert distraction. We are distracted by being lulled into focusing on the narrow range between the stomach and diaphragm — the area where most passes are caught and thrown. We are distracted by being led to believe that what matters is the proper tallying of the number of passes made by the players in white. It is easy to see from this perspective why it is necessary that the players on the video are presented as real and not fake. To do otherwise would immediately defeat the purpose of the experiment, which is to deflect the unsuspecting viewer’s attention away from any of the many social clues as to what is really happening. Consciously or unconsciously, the experiment is designed to divert the viewer’s attention so as to spectacularly blindside him or her when the presence of the gorilla in their midst is gloriously revealed.

To call the experiment deceitful is to do no more than call attention to a mainstay of contemporary experimental psychology: to tell the subject only what the experimenter wants to tell him or her. The deck has to be stacked. Otherwise, the experiment could not be nearly as controlled as the rigorous protocols of experimental psychology require. Unnecessary information could bring in new, unwanted variables, making the experiment more unpredictable and less scientific. Consider the following real life analogy (which has occurred numerous times) to the famous invisible gorilla experiment. You are watching on television a much-anticipated major sporting event when suddenly the totally unexpected happens: an ugly brawl between spectators breaks out in the stands; a fan leaps onto the playing field and races to embrace (or attack) a targeted player or a streaker bursts onto the scene of action. Within moments, thousand upon thousands of onlookers become riveted by the actions of the lone interloper.

As the great social psychologist Erving Goffman taught us, we learn by social cues. When these social cues are unanimous (as they rarely are) it becomes almost impossible to ignore them. If you walk into a room and everyone is pointing to a suspected but imaginary leak in the ceiling, you are compelled to join the search. Analogously, if you are watching a film in which everyone in its acting as though something that has just happened did not happen, you are unconsciously persuaded to go along.

The lesson from their celebrated experiment, according to Chabris and Simons, is that we do not see what we do not expect to see. We do not see the gorilla because we did not expect to see the gorilla. The fact that all six players in the film, of course, did see the gorilla, but pretended not to, is so unimportant to them that it is not even mentioned.

From our perspective, however, it is of crucial importance that the film — depicting something that could not conceivably have happened — is presented as real. I believe that in a thousand such real life cases — in which no one, of course, would have been tipped off that a freaky intruder was about to appear — not once could the figure in the gorilla suit go totally undetected by all of the players who were present. Lulled into momentarily forgetting that we are watching stooges, we unconsciously project our own blindness to the gorilla upon the six players making the deception, when it is revealed, that much more astounding.

Not seeing what we don’t expect to see, the authors tell us, is an example of what is called “inattentional blindness.” It is reminiscent of what over fifty years ago the great interpersonal psychiatrist Harry Stack Sullivan called selective inattention, and is itself an example of how basic concepts in psychodynamic theory are sometimes appropriated by cognitive psychology, renamed and claimed as their own. But there is a difference. The so-called inattentional blindness in psychodynamic theory is motivated and (especially according to Harry Stack Sullivan) anxiety driven. We see what we expect to see because it reassures us to see the familiar. We don’t see what we don’t expect to see because to do so would make us anxious. This is another way of saying we see what we expect to see because we want to see it and don’t see what we don’t expect to see because we don’t want to. It is a subtle but substantially different perspective from that of cognitive psychology which locates the root of the problem in a flaw in the attentional, perceptional apparatus.

That said, let’s bring the human equation fully back in the picture and revisit the gorilla video from the standpoint of psychodynamic theory. From that standpoint, we don’t see what we don’t expect to see, because we have been accustomed to a different context — the context of the comfortably expected. By contrast, to expect the unexpected is to recontextualize your thinking, to recognize and detach yourself from your previous context, which now is no longer relevant, and rapidly reorientate yourself to a different frame of reference. Never an easy task. Viewed this way it makes sense to stick with what we know. No doubt we would make fewer mistakes if we could train ourselves to become more illusion-wary, as the authors seem to advocate, but what about the errors that would be made from our loss of focus on the complicated details of our high-tech world? You can’t have it both ways.

Counting passes, the authors imply, was a necessary ruse to deflect the viewer’s attention. It is worth asking why is this necessary? What would be changed if the viewers were told instead to watch a one-minute video and afterwards try to remember what they had seen? Surely, in such a scenario no one would dream that an off-camera girl in a gorilla suit was momentarily about to take center stage. No one, that is, could therefore expect to see such an occurrence, yet — as by now should be obvious — that is exactly what everyone would see. The Chabris-Simon rule that you don’t see what you don’t expect, would no longer apply.

Why? Because of a sudden intrusion of what might be called context dissonance. This is when the perspective of two serial or overlapping events suddenly become radically disjunctive. Think of looking straight ahead, focusing on the green light and blissfully unmindful of the speeding cyclist on your immediate left who is running the red light. In this case, part of the context dissonance is caused by the incongruent physicality of the two disparate vehicles: the car, three-dimensional, bulky, noisy, eye-catching and fast; the bicycle, stick-thin, two-dimensional, noiseless and ghost-like. The one as hard to overlook as the other is nearly impossible to anticipate.

Then there is scenic dissonance. This is when, for example, you are looking at the potholes in the pavement you are walking on and do not see the pole you are about to smack into. Or, conversely, when you are studying the faces of the crowd that is approaching and do not see the cellar trap door ten feet ahead that has just opened up to receive a delivery. To avoid such mishaps, the veteran pedestrian will intuitively be alert both to the requirements for face recognition and the need to maintain safe footing. A focus narrower than five or six feet will obviously not do.

We immediately see why the gorilla — so hard to see in the video — is impossible to miss in real life. In the experimental example we are deliberately assigned a highly specific task requiring an exceedingly narrow focus (the area between the stomach and diaphragm and between floor and stomach). In real life for reasons that should be clear, we look at scenes: people, contexts and surroundings interacting in some kind of narratively cohesive picture. We look at scenes because we get thousands of times more information than we do when we focus on tiny details of reality. We look at scenes, first, to reassure ourselves we are where we want to be, in a safe place, in an interesting place, and so on. Afterwards, we can pick and choose from a cornucopia of details.

In a real life gymnasium or playground, the six players throwing the basketball around would have an unimaginable number of visual and interpersonal cues to alert them to the sudden presence of the incongruous intruder in the costume gorilla suit. Viewed this way, the Chabris and Simons video begins to look less like an experiment and more like an illusion performed by a stage magician. There is, however, a key difference: with the magician, we attribute our inattentional blindness to the skill of the performer, with the video, we assume — mistakenly, I believe — the fault lies in ourselves.

At this point, it is worth comparing the context of a random slice of real life with the artificial world of the structured psychological experiment. On the one hand there is uncertainty, unpredictability and countless uncontrolled variables. The participants are real people engaged in varying degrees in what will be a range of individual experiences. How different this is from the contrived, one-dimensional, toy-like world of the experimental psychologist. Contrary to what has become the daily fare of cognitive psychologists, it does make a difference if the participants in an experiment are stooges who are playing a role. From the psychodynamic point of view, especially, the consequences are momentous: to the extent that people are playing a role in these experimental setups (and they often are) any authentic, interpersonal, social interaction — an admittedly major determinant of our behavior-is inhibited.

It follows the level of anxiety and motivation will vary accordingly on whether one is living their life in real time, or volunteering to take part in an abbreviated psychological experiment. Although the point could not be more obvious, we worry more about something that is real than something that is not: how we feel about a character in a movie whom we like who suffers a horrible death is qualitatively different from how we feel when a similar fate befalls someone we personally know. In real life there is an almost inexhaustible number of things that could trigger our anxiety level. To the person who is volunteering to be a guinea pig in a serious psychological experiment there is manly the desire to please the psychologist or the proctor, plus the almost universal performance anxiety evoked by the prospect of participating in a novel situation. In real life there could be any number of determinants and motivations for what we do: social, narcissistic, sexual, aggressive, interpersonal, pragmatic and so on. In the world of the artificial experiment, in addition to performing competitively, there is perhaps a vague curiosity and seeking for a fresh stimulus. Because of this, what we do in the real world tends to become an embedded social experience. By contrast, for the person volunteering to be in an experiment, there will be scant personal meaning, and almost none of the expressive richness which characterizes human behavior.

For all these reasons, the experience of participating in a psychological experiment (such as watching the one-minute gorilla video) will lack the meaning, the gravitas and the consequences of everyday life. Although there can be anxiety depending on the extent to which the person approaches the experiment as a competitive game, in which their self esteem is at stake, it will not be the same. Dan Ariely jokingly mentions how college students responding to campus advertisements for participation in time-consuming, complicated psychological experiments are sometimes motivated primarily by the quest for extra beer money, while Chabris and Simons point out that the actors and film crew involved in the shooting of the original one-minute video were all students enrolled in their undergraduate psychology classes (where at least there would be motivation to obtain a passing grade). That said, Chabris and Simons, on more than one occasion refer to the fact that their gorilla video won the Ig Noble award (a parody of the real award, granted to seemingly trivial accomplishments which inspire laughter and surprisingly impart wisdom: prompting the famed evolutionist, Richard Dawkins, upon reviewing the gorilla video along with the 92nd Street Y audience, to afterwards gush, “I think every judge, lawyer and jury ember should be made to look at this film before every trial”).

Gerald Alper

Author Of God And Therapy

What we believe when no one is watching

(the above is an excerpt from my recent book, “The Elephant In The Room”).


Author. Psychotherapist. Writing about psychology for all to read. I also interview scientists.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store
Jerry Alper

Author. Psychotherapist. Writing about psychology for all to read. I also interview scientists.