The affect heuristic can influence decisions in essentially any domain, and it has been demonstrated that we tend to rely on this heuristic more in situations where there is significant time pressure¹. This means that if we are ever given an important decision to make quickly, we may resort to this heuristic, which has the potential to lead us to choose poorly.

Furthermore, reliance on the affect heuristic can limit us. We may be unwilling to put ourselves out there because of some gut feeling that we won’t succeed. This could prevent us from stepping out of our comfort zone at times when doing so could benefit us.

The affect heuristic can be used to make positive changes within society, especially through public health campaigns. These campaigns often use fear appeals to decrease certain unhealthy behaviors within society by sharing statistics, information, and images that lead people to experience negative affect in regard to that behavior. The efficacy of fear appeals has been hotly debated over the years but, in theory, this is a potentially beneficial application of the affect heuristic.

On the other hand, the affect heuristic can also result in systemic challenges. If someone in a leadership position is given an important decision to make, they may come to a conclusion based not on logic and reason but based on their emotions. This is more likely if they are tired or are under time pressure, as we tend to rely on heuristics more when we do not have sufficient mental resources to make an effortful, well-reasoned decision.

Dual process theory posits that we have two cognitive systems: one that is automatic and one that is effortful. It has been suggested that the affect heuristic results from the former.² In addition to this, the affect heuristic occurs because our affective, or mood, state alters our perception of the risks and benefits of a particular outcome.

Dual system thinking

Dual process theory is a foundational theory in cognitive psychology. It suggests that humans have two distinct cognitive systems for decision-making. The first, System 1, is fast, effortless, automatic, and emotional, while the second, System 2, is slow, effortful, deliberate, and logical.

There is a common misconception that, because it is based in emotion, and not logic, System 1 is maladaptive and always leads to poor decision-making, while System 2, which is rooted in reason, is superior in every way. However, as Daniel Kahneman pointed out in his book, Thinking Fast and Slow, both systems have their pros and cons.³ System 1 thinking is beneficial in situations when there is no time to deliberate; an immediate decision must be made. This kind of automatic thinking allows us to make the quick decision to hit the brakes when someone cuts us off on the highway or to jump into action to perform the Heimlich maneuver on someone who is choking. In these situations, there is no time to sit around and make a slow, effortful decision.

The affect heuristic results from System 1 thinking. Instead of making a well-reasoned decision, when we rely on the affect heuristic, we make a quick choice based on our emotional state. In some cases, this can be to our benefit, in others it may lead us to make different decisions than we would have, had we taken the time to weigh our options.

Risks and benefits

Another factor that contributes to the affect heuristic is our perception of the risks and benefits of making a certain decision. Our mood state influences risk assessment, which in turn influences our behavior.

When we experience positive affect, we tend to perceive an option as being low risk and having high potential benefits. In contrast, when we experience negative affect, we perceive the option as being high risk and having few potential benefits.⁴ Naturally, if we feel that selecting a certain option will lead to a big payoff, with little chance of negative consequences, we feel more inclined to make a decision in its favor. Along the same vein of reasoning, if we feel that choosing a certain option is extremely risky and believe that we will not get much out of it, we are unlikely to select it. As such, the impact our emotions have on our perceived risks and benefits of a given outcome can have a significant effect on our decision-making.

No matter our age, our careers, or where we live, we’re all faced with decisions each and every day. Granted, some are more important than others, but even seemingly small decisions can have significant consequences. In order to ensure that we’re making the best choices we can, we need to be aware of the different heuristics and biases that can influence our decision-making. This way, we can learn how to avoid them, or at least recognize them in other people.

By being aware of the fact that our emotions can impact our decisions, we can start to avoid the affect heuristic. When faced with big decisions, we should not rely exclusively on System 1 thinking. By taking the time to think logically about the choice we have to make and considering all possible options, we prevent ourselves from taking mental shortcuts to reach a conclusion. Furthermore, being aware of one’s emotional state is useful for avoiding the affect heuristic. If we can recognize that we are feeling a certain way, such as happy, sad, or angry, we can acknowledge that our emotions have the potential to affect our decision-making and, in doing so, remind ourselves of the importance of using System 2 thinking. Finally, if we’re ever given an important decision to make when we’re feeling particularly emotional, whether it is a positive emotion or a negative one, it can be a good idea to put off making the decision until our emotional state is closer to baseline. This will help to ensure that our choice is not impacted by extreme emotions.

In 1980, Robert B. Zajonc highlighted the importance of affect in decision-making in “Feeling and thinking: Preferences Need No Inferences”.⁵ He suggested that all perception has an affective component; he wrote: “We do not just see “a house”: we see a “handsome house”, an “ugly house”, or a “pretentious house”.”(p.154). Furthermore, Zajonc demonstrated that our first response upon perceiving a new stimulus is often an emotional one. This was contrary to the accepted belief at the time, which was that affective states only come about after several cognitive and perceptual processes have been carried out. However, Zajonc argued that affect is the only constant; when we perceive a stimulus, we will always feel some emotion towards it, but the level of cognitive activity we experience is subject to vary.

The theory that emotions can be felt prior to, or even in the absence of, further cognitive activity, opened up the floor to the discussion of how emotions can influence decision-making. In 2000, Paul Slovic et al. published a paper titled “The affect heuristic”⁶, in which they introduced the heuristic. Additionally, they presented experimental findings to demonstrate how our emotions influence our evaluation of the risks and benefits of a given behavior.

Public health campaigns often attempt to use the affect heuristic to encourage people to practice healthy behaviors and avoid maladaptive ones. They do so through fear appeals, which serve to scare the population by presenting the worst-case scenario consequences of continuing to partake in certain behaviors. The classic example of this is anti-smoking campaigns. Pictures are commonly used to deter people by smoking, with images of the teeth and lungs of longtime smokers displayed on the sides of cigarette packages in some countries, like Canada. Additionally, these public health campaigns stress the severity of the consequences of smoking, which include increased risk of cancer, stroke, and gum disease.

The results of a survey conducted by David Hammond, Geoffery T. Fong, and their colleagues, were published in their 2004 paper, “Graphic Canadian Cigarette Warning Labels and Adverse Outcomes: Evidence from Canadian Smokers”.⁷ The idea behind the warning labels on cigarette packages is that they would make smokers fearful of the negative consequences of smoking and that this arousal would prompt them to try to smoke less or quit altogether. They found that, of the 616 Canadian smokers surveyed, 20% reported smoking less as a result of the warning labels. Furthermore, it was demonstrated that greater negative affect in response to these labels, which were most commonly fear and disgust, was associated with a greater likelihood of quitting smoking, attempting to quit smoking, or cutting back on the number of cigarettes smoked three months after the warning labels were introduced.

Negative emotions, like fear and disgust, pushed people to reduce their smoking, which perfectly highlights how our emotions can drive our behaviors. Here, we see how the affect heuristic is not always irrational or illogical; the consequences of smoking are very serious, and quitting is a logical choice. In this case, the affect heuristic is actually beneficial.

We think of statistics as cold, hard facts but our interpretations of them are not always objective. The emotions we feel when we view certain statistics can influence the inferences we make from them. Moreover, our emotions can be manipulated by the way the statistics are presented.

In a study conducted by Slovic et al. in 2000, a group of psychiatrists and forensic psychologists were tasked with evaluating the likelihood that an inpatient with a mental illness would commit a violent act within six months of being discharged from the hospital. All participants were provided with statistical evidence to inform their decision. For half of the participants, this information was presented in terms of relative frequency: “20 out of every 100 patients similar to Mr. Jones are estimated to commit an act of violence”. The other half were given the statistics framed in terms of equivalent frequency: “patients similar to Mr. Jones are estimated to have a 20% chance of committing an act of violence”. In the relative frequency group, 41% of participants said the patient should not be discharged while only 21% of participants in the equivalent frequency group said he should not be discharged. In both cases, the same numbers were presented; they differed only in the way they were presented. Slovic et al. hypothesized that this was because the low probability of 20% elicited images of a single individual who is very unlikely to behave in a violent manner. This benign image would not cause any of the participants’ moods to deviate from baseline. The equivalent frequency, on the other hand, brought forth images of several violent individuals who are comparable to the individual in question. The images of many people committing violent acts induced negative mood, eliciting emotions such as fear, which made the participants less willing to discharge the patient.⁸

Even though presenting statistics in different ways does not change the objective values, it can influence our affective responses. Our emotions may then impact the way we interpret the statistics and thereby influence our decision-making. If Slovic et al.’s study had been a real-world example, whether or not the patient was discharged may have hinged on the way the statistics were presented to their clinicians.

What it is

The affect heuristic refers to how we can make judgments and decisions more efficiently – although not always more accurately – by relying on our emotions.

Why it happens

The affect heuristic can be explained by dual process theory, which states that we have two distinct cognitive systems for decision making, one that is automatic and one that is effortful. The affect heuristic is a product of the automatic system, as it arises from our affective state. Our emotions can also alter our perception of the risks and benefits of a certain outcome, which is another factor that leads to this heuristic.

Example 1 – Fear appeals

Public health campaigns have used the affect heuristic to deter people from engaging in unhealthy behavior by sharing scary or disturbing information. Anti-smoking campaigns, for example, lead to information about the consequences of smoking and pictures of diseased gums and lungs being added to cigarette packages in Canada. A survey found that the more negative emotions people felt in response to these warning labels, the more likely they were to cut back on their smoking or even quit altogether.

Example 2 – Interpreting statistics

Statistics presenting the probability of a certain event occurring have the ability to elicit emotional responses from us. These responses can be manipulated by the way the information is framed. For example, clinicians in a study were less willing to discharge a psychiatric patient when told that 20 out of every 100 individuals like him committed a violent act in the six months after being discharged than were clinicians who were told that 20% of patients like him acted violently in that same time frame. This is because the relative frequency, or percentage, brought to mind the image of an individual who had low odds of behaving violently, while the equivalent frequency, 20 out of 100, brought to mind the image of several people committing violent acts. The latter elicited more negative affect in the clinicians, thereby making them less willing to discharge the patient.

How to avoid it

Knowledge of the affect heuristic can remind us to take our time making important decisions, so that we can come to a conclusion through logic and reason, instead of making an immediate choice based on our emotions.