The Seductive Allure of Uncertainty

Amongst the forests of trees cut down in support of self-help books on dating, some not inconsequential percentage of lumber has probably been exclusively dedicated to variants on the theme that one must “play hard to get” to find love. If you never heard this expression, I would be curious to know what solar system you’ve just arrived from. And for you, my alien friend, I say welcome to our planet, and please allow me to explain. As it’s been passed down through the ages, the story goes that If a person wants to attract the interest of another toward whom they have romantic inclinations, they should be aloof and slightly stand-offish, so as to gain the attention and interest of their betrothed. Popular self-help manifestos such as “Why men love bitches,” are based on the idea of making oneself more attractive by decreasing one’s availability (to put it mildly). Going back several hundred years, even Juliet, from Shakespeare’s most famous play, knew as much when she told Romeo that “…if you think it’s too easy and quick to win my heart, I’ll frown and play hard-to-get, as long as that will make you try to win me.” I remember hearing some variant on this theme (“Don’t be too eager”) from older boys when I was a scrawny young fellow just becoming interested in girls for the first time.

Erin Whitchurch and colleagues from Harvard University were interested in how this seeming truism (the Uncertainty Principle), conflicted with another observation from the social psychological literature, which is that people tend to like those who like them back (known as the Reciprocity Principle). Interested in testing this principles against each other, they designed a study whereby 47 women viewed Facebook profiles of a set of men who, they were told, had previously viewed their profiles and rated how much “they would get along with each woman if they got to know her better.” A subject knew that a given man either liked her a lot, liked her about average or they were uncertain as to whether the man liked her or not. Then she would rate each man on a number of different dimensions including how much they might like him as “a potential boyfriend” and how much they would be interested in “hooking up” with him.

The results showed that women liked men who liked them a lot more than men who liked them a little, supporting the Reciprocity Principle; that is, we like those who like us back. But the study also supported the Uncertainty Principle (that we like those who we are uncertain about) by showing that women liked men about whose feelings they were uncertain more than men who said they liked them a lot. They also reported thinking a lot more about these men. The authors mention that although this advice has often appeared in the popular press, social psychological research has never confirmed it. The authors also point out important constraints and limitations that bear on the ecological validity of the effect. Among these are the fact that participants didn’t know anything about the men and it’s not clear that this effect would hold after meeting someone and/or beginning a relationship. Perhaps, as they suggest, this finding would be most applicable in the context of online dating, in which people don’t know very much about the other person initially. Also, only females participated and there may be gender differences.

One important point to reiterate is that participants mentioned thinking about the men in the “uncertain” condition much more than in the other conditions. Although I’m not overly familiar with research on dating, romantic attraction, relationships, etc., the reason I was inspired to write about this study is because I’m quite interested in the effect of uncertainty on cognitive and attentional processes and decision making, topics that a handful of recent studies have addressed. One 2010 study from researchers at Cornell found that people were more distracted by hearing one person on a cell phone nearby vs. two people having a conversation, the suggestion being that it was the unpredictable nature of the one-sided conversation that led to participants’ increased distraction. Zachary Tormala at Stanford has performed studies in which he has found that expert advice expressed with low certainty can be more persuasive than that expressed with high certainty. Tormala says that when an expert, say a restaurant critic, is unsure of themselves in a review of a restaurant, this is surprising to people. And “…surprise increases readers’ interest in and involvement with the review, which is essentially a persuasive message, and this promotes persuasion,” says Tormala. “Experts … get more attention and can have more impact when they express uncertainty.” In standard human fear conditioning experiments, the strongest fear conditioning is generally achieved when you shock participants only about a third of the time. That is, the strongest fear responses are generated when participants are maximally uncertain as to when they’re going to be shocked. That’s when you’ve really got their attention.

So, over a variety of different domains and outcomes, uncertainty is the variable common to all of the above situations. From an adaptive perspective it makes sense that we would direct extra attention to unsolved vs. solved problems. As organisms whose very survival is dependent upon our ability to learn about the world around us, we often have no choice but to devote an inordinate amount of attentional energy to the unknown. But from a mechanistic point of view, what motivates this orientation?

There is a rather large scientific literature discussing the role of reward signals in learning and uncertainty. And while its well-established that learning is largely dependent on reward systems, primarily the dopamine system, it’s also been shown that uncertainty alone is subserved by the same system. Going back to the study at hand, it doesn’t seem outrageous to imagine that participants had conflated the reward signal associated with uncertainty about being liked with the reward signal associated with liking someone.
This wouldn’t be surprising as the same dopamine neurons that preferentially report subjectively pleasant events also seem to signal attention-inducing ones. Dopamine neurons fire much more strongly to unexpected rewards and they may also fire strongly when presented even with the prospect of such a possibility, a kind of second-order reward effect. So, the effect could be framed as a kind of neural parlor trick, a technique whereby one can hijack the reward system of another person, causing that person to experience feelings that they then misinterpret.

I’m concerned with how science is presented to the public and how misunderstood scientific findings often become cultural “memes” that permeate the culture and plant incorrect ideas about human nature inside of people’s heads. Whitchurch’s study has already generated just these kind of sensationalistic and over-simplified headlines:


Men should play hard to get, find psychologists

It’s important to keep in mind that the more rewarding your dream girl or guy finds uncertainty, the more likely it is that this “technique” will work on them. And there is evidence that individuals vary in how sensitive they are to uncertainty, so this may not work on everyone. Furthermore, if their attraction to you is driven largely by uncertainty, then what’s going to happen once the uncertainty is no longer there?

(a page from an imagined self-help book):

“You shouldn’t play hard to get. Why? Because, as Harvard researchers have pointed out, it will attract (wo)men to you, but it’s an illusion. They might not be attracted to you because they like you, but because you’ve increased their attention to you through manipulating uncertainty as to how you feel about them! While this might work for as long as you maintain that uncertainty, remember this is not the same thing as someone liking or loving you. While human beings might be wired to pursue certain situations and people because of this, if you’re a healthy, well-adjusted person, you don’t want that kind of person in your life, because they’ll always be interested in chasing the unknown and once they’ve “figured you out,” they’ll be on to the next mystery.”

The Rational Vulcan

“It is more rational to sacrifice one life than six.”

– Spock

Consider the following two situations:

Situation # 1: You are among a group of 25 people who are hiding during World War II in the attic of an old country house while a group of enemy soldiers, who have been searching for your group and will kill everyone if they discover you, are on the floor below. The slightest sound from anyone in your group will give you all away. Your baby makes a face as if to cry, and you quickly cup a hand over the baby’s nose and mouth to keep it quiet. You realize that if you takes your hand away, the baby will cry, and your group (including you and the baby) will be discovered and killed, but if you keep your hand in place, the baby will suffocate and die, but everyone else will survive. What should you do?

Situation #2: You are a participant in an experiment of the following nature: There is a revolving $10 pot and another person will repeatedly offer you an amount varying from $1 to $9 from that pot, keeping the rest for himself. If you refuse any given offer, you both get nothing. The size or number of offers you refuse will have no affect on subsequent offers. You will never encounter this person ever again. Here’s what the experiment looks like:

What is the lowest offer you should accept?

Both of the above dilemmas suggest difficult but somewhat obvious utilitarian choices (utilitarian=providing the maximal benefits for all). If you’re thinking rationally (like Spock), you should kill the baby to save the group of 25. And in Situation #2, you should accept any and all offers, even if you’re only unfairly offered $1 (while the giver keeps $9), because something is better than nothing. However, perhaps not surprisingly, humans often don’t make the rational decisions in situations like these, and often rely on emotional responses to lead them towards rationally incorrect choices. I will discuss the two psychological mechanisms by which decisions such as these are made, offer some compelling examples showing how neuroscience is shedding new light on the science of moral decision making and discuss the real-life implications of this research.

The Role of Emotion and Reason in Human Decision Making

Philosophy has long been concerned with understanding the basis for human morality. Rationalist philosophers, such as Plato and Kant, characterized moral judgment making as a rational exercise, based upon deductive reasoning and cost-benefit analysis. Contrastingly, philosophers such as David Hume and Adam Smith held that automatic emotional responses played a primary role in moral judgments. And although many contemporary psychologists and philosophers have continued to favor one position over the other, modernists are increasingly integrating these two views, suggesting that moral decisions are the result of the confluence of both fast, automatic emotional responses and controlled, deliberative reasoning. In recent years, psychologists have been using the tools of neuroscience – namely, fMRI or functional magnetic resonance imaging – to help better understand the mental processes underlying such “dual process” models.

In order to examine how these two systems interact in decision making, we’ll look at two experiments.

The first experiment utilizes fMRI to shed light on the conditions under which we might engage emotion vs. reason when making a moral judgment. The second experiment involves patients who have suffered brain damage in a region of the brain known to play a role in social emotional responding, and we’ll look at how this type of localized damage can actually lead to better decisions (in a utilitarian sense) in some moral decision tasks.

Moral Decisions and the Trolley Dilemma

The first experiment we’ll discuss comes from a problem originally discussed by philosophers Phillipa Foot and Judith Jarvis Thompson, known as the “trolley” problem, which presents the following two dilemmas:

(1) A train is speeding down some tracks. You glance ahead and notice that there are 5 people working on the track who don’t see the train coming and will be killed. However, there is a switch within your reach, which, if you pull it, will switch the train to another set of tracks, saving those five people but killing one person working on the other track. Is it ok to pull the switch?

(2) Again, the trolley is headed for five people. You are standing next to a man on a footbridge overlooking the tracks and if you push him off the bridge and in front of the train, it will cause the train to stop, saving the five. Is it ok to push the man off of the bridge?

Most people say yes to #1 (its ok to pull the switch) but no to #2 (not ok to push the man), even though the situation are identical in a utilitarian sense. The presents a puzzle: Why is it the case that most people make those decisions?
And what kind of mental calculus are people doing in order to consistently make these choices?

According to Harvard psychologist Josh Greene, the difference lies in the emotional responses we experience to either case. In the track switching case, our role in the man’s death is somewhat passive. He happens to be on the other track and we happen to pull the switch that directs the train to the track, but we’re not directly involved in his death. It doesn’t feel wrong – or at least not wrong enough to overwhelm our rational analysis of the situation (which is that 5 lives are worth more than one.) Greene refers to this scenario as the “impersonal case.”

The footbridge situation – ”the personal case” – is quite a different scenario. We’re playing an active role in the man’s death; the idea of pushing the man certainly “feels” more wrong than the idea of pulling the switch. I would venture to say that for many people it feels a little like murder and would evoke an extremely negative emotional response. This emotional response would seem likely to drive the subsequent decision to obey the rational calculus of the situation and let the man pass on by. This explanation, if correct, offers some specific predictions regarding the neural networks that should be actively driving these decisions. Greene ran people through the experimental paradigm while they were in the scanner and found the following:

– In cases where people said it was ok to pull the switch, active brain regions were those involved in deliberate reasoning (the dorsal lateral prefrontal cortex (DLPFC), and the inferior parietal lobule). In other words, in order to make the decision to pull the switch, people seemed to engage deliberate, rational thought processes.

– In cases where people said it wasn’t ok to push the man, active regions were those involved in the processing of social emotions (the medial prefrontal cortex (MPFC), and the posterior cingulate). The thought of pushing someone in front of a trolley seemed to evoke a strongly negative emotional response that drove moral dissaproval of the act.

But perhaps the most interesting finding was revealed in the brain data of those subjects who decided it was ok to push the man off of the bridge. Greene (2004) found that the selection of a more utilitarian choice revealed a conflict between the “rational” and “emotional” systems (I’m quoting the terms “rational” and “emotional” because these are not entirely distinct systems in functional terms, but rather quite interconnected). Additionally, he found activation in the anterior cingulate cortex, an area in which activation is thought to reflect conflict between competing brain processes. In other words, the thought of pushing someone in front of a trolley would evoke a strongly negative emotional response, which would then have to be overridden in order to the make the more utilitarian or rational response.

Again, most people chose not to push the man over the footbridge. Greene’s experiment strongly suggests that it was activation in brain regions known to be active during emotional responding that are responsible. But an even better test of whether a particular brain region is responsible for a given behavior is to look at people who have damage to that area of the brain. That is, would people with damage in the “social emotional” centers of the brain be more likely to push the man off of the bridge? A group of Italian researchers (Moretto 2009) recently recruited people with damage to a region of the brain active during social emotional responding (the vmPFC) to test Greene’s claim.

Vmpfc damaged brains above (orange highlights show the focal point of the damage).

These patients participated in the same task as in Experiment #1 (the trolley task). And as predicted, brain damaged patients more often chose to push the man off the bridge to save the five people on the tracks. This is presumably because they didn’t experience an emotional signal (which would normally have been reflected via activity in the mPFC) that would prevent them from endorsing such an action, thereby allowing deliberative mental processes to reign supreme. Simply put, these patients’ lack of emotional response led them to the more rational choice. Does this data suggest mean that people with vmPFC damage are generally better equipped to make more rational moral decisions? Although this kind of brain damage does sometimes result in the kinds of limited benefits described herein, it also leads to a much larger set of deficits, including difficulties making economics decisions as well as a tendency to exhibit exaggerated anger, irritability, emotional outbursts and tantrums, particularly in social situations involving frustration or provocation. People with this kind of brain damage also often have difficulty making sound economic decisions (Damasio 1994).

Real Life Implications
One of the biggest challenges inherent to experimental psychology lies in the push and pull between naturalism and control (the more control we impose upon the conditions of the experiment in order to isolate the variable of interest, the less “ecologically valid” the results are likely to be.) The moral choices people make from the comfort of a psychology lab may or may not replicate out in the real world. But naturalism is not the most important aspect of the trolley problem. What is important is the mental processes that underlie two conditions which differ not in terms of their rational calculus, but only in the personal role we play in the outcome. Consider the case of Flight 93, the ill-fated plane that crashed into a Pennsylvania field on 9-11. The White House was notified about the possible hijacking about 50 minutes before the plane came down. And in that time period, a difficult decision was made. In an interview with Tim Russert shortly after 9-11, vice president Dick Cheney talked about the decision:

Yes. The president made the decision … that if the plane would not divert … as a last resort, our pilots were authorized to take them out. Now, people say, you know, that’s a horrendous decision to make. Well, it is. You’ve got an airplane full of American citizens, civilians, captured by … terrorists, headed and are you going to, in fact, shoot it down, obviously, and kill all those Americans on board?”

And although this decision is difficult to argue against, it was certainly still a difficult one to make. As in the trolley problem, it requires that rational, deliberative thinking take precedence over the negative and aversive emotion, the revulsion and guilt, that most people would feel if forced to play an active role in the death of one (or several) innocent humans. And although the president and his cronies had to make the decision “on paper”, the fact of the crash obviated the need to actually issue the order to shoot the plane down. In this sense, the incident resembles a lab experiment in which decisions aren’t actually enacted but are merely theoretical. The tougher decision would have come later, with the order to fire. Furthermore, imagine the intense internal conflict for the pilot who would have been ordered to actually pull the trigger. It’s a reminder why military organizations train their soldier to blindly follow orders. A soldier is optimally neither rationally analyzing the moral parameters of nor reacting emotionally to any given situation, but only acting upon his orders. If a military commander could peer into the brains of a soldier faced with such a dilemma, he would ideally want to see none of the brain activity found in Greene’s conflicted rationalizers.

So what does this all mean for you and me? For one, its should serve as a reminder that there are times when we’ll arrive at the optimal solution to some moral quandary not by “trusting our gut” but rather deliberately and rationally working through a problem. We need to develop a healthy distrust of our common sense instincts, as they can often mislead us. But that’s not to say that rational deliberation will always lead us to respond more accurately to moral challenges. On the contrary, sometimes the emotional system is exactly the tool for the job. After all, the Enterprise couldn’t have survived without both Spock and Kirk.

Greene, J., Nystrom, L., Engell, A., Darley, J., & Cohen, J. (2004). The Neural Bases of Cognitive Conflict and Control in Moral Judgment Neuron, 44 (2), 389-400 DOI: 10.1016/j.neuron.2004.09.027

Moretto, G., Làdavas, E., Mattioli, F., & di Pellegrino, G. (2010). A Psychophysiological Investigation of Moral Judgment after Ventromedial Prefrontal Damage Journal of Cognitive Neuroscience, 22 (8), 1888-1899 DOI: 10.1162/jocn.2009.21367

Damasio, A.R. (1994). Descartes’ error: Emotion, Reason and the human brain. New York: G.P. Putnam’s Sons.

Acute Stress Modulates Risk Taking in Financial Decisions

Increased anxiety leads to increased reliance on biased risk taking in financial decisions. That’s according to a new study from researchers at Rutgers University.

The study was premised on an oft cited observation by Kahneman et al that people are more sensitive to potential losses than to potential gains, preferring to make riskier choices in the face of potential loss and more conservative choices in the face of potential gains. At first, this might sound counterintuitive: if people are loss averse, then why would they make riskier decisions in the face of potential loss? I should probably read the original Kahneman paper but my intuition is that because loss is so painful, people avoid it at all costs, preferring rather a low probability, large loss to more frequent but smaller one. For example, in this study, participants had to choose between a 20% chance of losing or winning $3.00 versus an 80% chance of losing or winning .75. Of course, it should quickly become obvious that neither choice is riskier than the other in other the loss or gain condition. Over repeated choices of this type, one is likely to lose or win the same amount no matter which choice is made. That being the case, we should see that people on average would choose between the two options at a rate of 50/50. But that’s not what we find. In the loss condition, subjects are more likely to choose the “risky” option, the choice with the lower probability of occurring, e.g. $3.00 at 20%.
But in the gain condition, people are more likely to choose the “conservative” option, the choice with the higher probability of occurring, e.g. .75 at 80%.
It seems that people are more sensitive to the pain of loss than they are sensitive to the reward of large gains. They would rather gain in more consistent, but smaller, increments, whereas they would prefer their losses to come less frequently, even if the loss will be bigger when it comes. Widely replicated over numerous experiments, this effect seems to be largely automatic and out of conscious awareness. The researchers posited that this effect would become even stronger under conditions of increased anxiety, as this would lead to decreased cognitive resources and increased reliance on decision making heuristics that are less cognitively demanding.