In other words, it is a type of heuristic in which emotional response, or "affect" in psychological terms, plays a lead role.
The affect heuristic is typically used while judging the risks and benefits of something, depending on the positive or negative feelings that people associate with a stimulus.
If their feelings towards an activity are positive, then people are more likely to judge the risks as low and the benefits high.
On the other hand, if their feelings towards an activity are negative, they are more likely to perceive the risks as high and benefits low.
[3] The affect heuristic received more recent attention when it was used to explain the unexpected negative correlation between benefit and risk perception.
An alternative thought to the “gut feeling” response is Antonio Damasio's somatic marker hypothesis.
These images then become “marked” by positive or negative feelings linked directly or indirectly to somatic states.
When a negative somatic marker is linked to an image of a future outcome, it sounds an alarm in the brain.
This hypothesis arose when observing patients with damage to their prefrontal cortex who had severe impairments in personal and social decision-making despite their other abilities.
These studies demonstrate how affect is an important characteristic of the decision-making process in many different domains and aspects as well as how it can lead to a strong conditioner of preference.
A study conducted by Winkielman, Zajonc and Schwarz (1997) demonstrated the speed at which an affective reaction can influence judgements.
Participants continued to show preference for the characters based on the first association, even though the second exposure was preceded by a different affective stimulus.
Slovic and Peters (2006) did a study on psychophysical numbing, the inability to discriminate change in a physical stimulus as the magnitude of the stimulus increases, and found that students more strongly supported an airport-safety measure that was expected to save a high percentage of 150 lives at risk as opposed to a measure that was expected to save 150 lives.
This is thought to have occurred because although saving 150 lives is good, it is somewhat harder to comprehend and thus the decision comes from the positive feeling associated with the higher percentage.
In the second experiment, students again had to make judgements about certain activities, but this time were given additional information about the risk and benefits.
In a study by Averbeck, Jones, and Robertson (2011), researchers look at how prior knowledge influences one's response to fear appeals.
Surveys were distributed which manipulated prior knowledge as low or high and two different topics: sleep deprivation or spinal meningitis.
Researchers found that individuals who had prior knowledge in a certain subject exhibited less fear and were least likely to fall prey to the affect heuristic as opposed to individuals that did not have prior knowledge who exhibited more fear and were more likely to fall prey.
[12] Research has shown that Americans are aware of climate change, but do not consider it to be a serious problem due to the lack of an affective response.
The processes consumers use to weigh the potential risk and benefits associated with purchasing such innovations are in constant motion.
Research has shown that affect plays a significant role in whether people choose to get screened for certain types of cancer.
Current research is now looking into how to communicate the risks and benefits of cancer prevention and treatment options.
It is for this reason that researchers are looking into using affective coding such as icon arrays to make numerical information easier to understand and process.
[6] An experiment composed by Hine and Marks (2007) examines the role of affect heuristics in maintaining wood-burning behavior.
The individuals analyzed in this study were 256 residents of a small Australian city where high levels of wood smoke pollution are present.
This would increase the chances of these participants choosing the cake over the fruit salad due to it being the more affectively favorable option.
In the same study they also tested the impulsiveness of the participants in moderating the effects of processing-resources of choice and at the time they were asked for their preference for the two snacks high cognitive demand chose the chocolate cake 84.2%.
This provides evidence that people's decisions can be influenced by affect heuristic in a relatively spontaneous manner from the stimulus, with little involvement of higher-order cognitive demand.
In a study by Sherman, Kim and Zajonc (1998), they investigated how long the induced effects of an affective response could last.
Research has shown that cigarette advertisements were designed to increase the positive affect associated with smoking and decrease the perceptions of risk.