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If we’re going to contend effectively with the damage wrought by fake news, then we first have to understand how it exploits our adaptive learning processes.
Fake news has dominated the news. Our susceptibility to disinformation campaigns has both shocked and alarmed the nation. Apparently unable to distinguish real from false claims, we seem to be gullible dupes who are ripe for conning by unscrupulous political agents, both foreign and domestic. Whatever happened to the lofty view we once held of ourselves as intelligent, rational actors?
My own answer is that we are indeed intelligent creatures. However, our intelligence is of a decidedly animal kind. We share with other animals the same biological machinery that allows us to adapt to most of the challenges that come our way. Yet, that machinery is not foolproof.
Let’s acknowledge that few animals can rely solely on inborn reactions to contend with the vicissitudes of survival. In light of this very real constraint, nature has evolved a generally successful solution: namely, learning from past experience.
The behavioral processes and neurobiological mechanisms of learning have been scientifically studied for over a century, beginning with the pioneering work of Edward Thorndike and Ivan Pavlov. We now know that surprise is the prime instigator of learning. When a surprising event happens, it is highly likely to become associated with an earlier event. A rat might come to fear a tone if the tone immediately precedes a surprising electric shock. However, if that same rat later receives the shock after a combination of the tone and a light, then the rat doesn’t also come to fear the light. Why not? Because the rat already expects the shock — it is predicted by the tone. Thus, the shock is unsurprising, and no light-shock association is formed.
How does this basic scientific research on surprise and associative learning relate to fake news? Here’s a prime example.
Have you heard that Hillary Clinton is running a child sex ring out of a pizza parlor in Washington, D.C.? Of course, this surprising revelation is blatantly bizarre. Yet, because this fake news story has gone viral, a strong association has now been formed between Hillary Clinton and the decadent pizza parlor. The sordid story has even been given a catchy moniker: Pizzagate! (If you haven’t before heard of this absurd association, now try to forget it!)
An extensive investigation into 10 years of Twitter usage recently found that fake news stories like this one reached more people, penetrated more deeply into the social network, and spread far faster than accurate news stories. Critically, those false stories proved to be measurably more novel than true stories. The greater novelty of false news stories led the authors of the study to suspect that the outperforming of false information over true information may have something to do with human nature, particularly with the role that novelty may play in attracting attention and updating our understanding of the world.
Recent research in human Pavlovian conditioning strikingly supports this suspicion. The work centered on changing the relations between numerous pairs of experimental stimuli: visual patterns and food odors. To create different intensities and identities of biologically meaningful stimuli, the researchers used odors corresponding with sweet and savory foods. Hungry participants learned associations between several different geometric visual stimuli and several different food odors through their repeated pairing. Then, unexpected changes were made in either the identity or the intensity of the food odor that followed each visual stimulus. For example, the odor of garlic might follow the visual stimulus previously paired with gingerbread, or the intensity of the odor of onions might be increased or decreased following the visual stimulus previously paired with a different intensity of onions.
Data from functional magnetic resonance imaging (fMRI) revealed that these unexpected odor changes prompted striking activity changes in specific regions of the participants’ brains. These neural changes are believed to reflect prediction error: the perceived disparity between the food odor that participants expected on a given trial and the identity or the intensity of the food odor that they actually received. The larger the prediction error, the greater the surprise, and the bigger the change in the associative connection.
This prediction error signal is deemed to be fundamental to all adaptive learning; it enables organisms to update the existing associations between signaling events and rewarding outcomes. The neural mechanisms of prediction have been found to be very similar in humans and many other animals. Fake news may thus hijack the basic attentional and associative mechanisms which the nervous system deploys in adapting to the ever-changing contingencies of the environment.
Certainly, much more needs to be understood about the dissemination of bogus stories and rumors. After all, such fake news can readily be exploited for political or monetary gains, as when newspapers expanded their circulation by exaggerating the chaos prompted by Orson Welles’s infamous 1938 radio broadcast of H. G. Wells’s War of the Worlds. Such exploitation may leverage another basic learning process — operant conditioning — in which responses that reap rewards are more likely to be repeated than those do not.
To conclude, I would suggest that, just as the generally adaptive process of Pavlovian conditioning may misfire and produce maladaptive phobias, fake news may promote its more widespread dissemination than legitimate news. The fault, in either instance, is not in the stars, but in ourselves — specifically, in our neural machinery.
