A recent study published in the journal Behavioral research and therapy shed light on how humans respond differently to threats versus rewards. Researchers have found that people tend to respond more intensely and more quickly to negative or threatening images than to positive or rewarding images. This phenomenon, called “negative effects,” was particularly pronounced in women compared to men.
The study was motivated by a desire to better understand why humans often respond more strongly to threats than to rewards. Evolutionary theories suggest that reacting to threats is more crucial for survival, because ignoring danger could lead to injury or even death. Although the rewards are important, missing the occasional positive experience is less likely to be life-threatening. The study aimed to explore this evolutionary perspective by examining how people’s emotions fluctuate in response to different types of stimuli, and how these reactions might be linked to susceptibility to anxiety disorders.
“An emerging literature highlights the dynamic (rapidly varying) nature of emotional reactions and their regulation. “We developed an ‘affectometer’ (now called Dynamic Affect Reactivity Task or DART) that allows us to assess emotional reactions with high temporal precision, in response to affective images,” said study author Michael D. Robinson, professor of psychology at North Dakota State University.
“We have published a number of papers using this technology. For example, Irvin et al. (in press) show that, even after comparing pleasant and unpleasant images of arousal and extremity, people still tend to have faster and stronger reactions to unpleasant stimuli. We link this to evolutionary perspectives on emotion (essentially, the idea that responding to a particular threat is more obligatory, for survival, than responding to a particular reward). In another article, Robinson et al. (in press) showed that people with higher levels of general mental abilities display more muted emotional reactions.
“In this case, we wanted to use the negative effects of DART (specifically regarding peaks, slopes, and prototypical patterns) to see if the Dynamic Emotion Probe can be used to understand individual differences in propensity to anxiety and threat. We used gender differences as a model because women tend to be more reactive to threats than men and have higher scores on anxiety and related disorders.
The researchers conducted a series of three experiments with a combined total of 375 participants, aiming to explore how individuals respond emotionally to positive (appetitive) and negative (aversive) stimuli. Participants were primarily undergraduate students from a Midwestern university in the United States.
Each participant was placed in a private room equipped with a personal computer to ensure focused and uninterrupted participation. The core of the experimental procedure was the dynamic effects reactivity task, which required participants to continuously evaluate their emotional state in response to a series of images.
The images were selected from the Nencki Affective Picture System and the International Affective Picture System, which are standardized sets of images known to elicit strong emotional reactions. These images included both appetitive images (e.g., happy people, children playing) and aversive images (e.g., car accidents, rotten food). Importantly, the images were equated with arousal and extremity to ensure that any differences in participants’ reactions were due to the positive or negative nature of the images rather than their overall intensity.
Participants used a vertical rating bar displayed on a computer screen to indicate their emotional state. The bar was labeled “very unpleasant” on one end, “very pleasant” on the other, and “basic feelings” in the middle. Participants were instructed to press the up or down arrows on the keyboard to move a cursor along the rating bar, continuously indicating how they felt in response to each image. For some participants, pleasant reactions were mapped to the up arrow, while for others they were mapped to the down arrow, ensuring that the task design did not bias the results.
The researchers quantified several key parameters from participants’ responses. They measured onset time (how quickly a reaction began after the image was presented), peak intensity (the maximum emotional response when the image was presented), and the slope of the reaction. (how quickly emotional intensity changed over time). Additionally, they calculated reaction prototypicality, which indicated the extent to which a participant’s response matched a typical reaction pattern averaged across all participants.
Robinson and colleagues found that participants’ emotional reactions to aversive images began more quickly than their reactions to appetitive images. This rapid onset of negative reactions supports the evolutionary theory that humans are programmed to quickly detect and respond to potential threats, which is crucial for survival.
The peak intensity of emotional responses was also higher for aversive images than for appetitive images. This means that not only do negative reactions start more quickly, but they also reach a higher level of emotional intensity.
Additionally, the slope of emotional change was steeper for aversive images. This finding is consistent with the idea that humans must quickly intensify their emotional response to threats to prepare for appropriate actions, such as fight or flight.
“The negative emotion system is more reactive than the positive emotion system,” Robinson told PsyPost. “In other words, we are predisposed to negative emotional reactivity. Threat sensitivity varies across individuals, however, and probes of the current type can be used to understand micro-momentary processes that might contribute to long-term anxiety and fear.
Another crucial finding was that negative reactions were more prototypical than positive reactions. In other words, reactions to aversive images were more uniform and consistent, suggesting a more automatic and perhaps hardwired response mechanism to threats.
“We really like the ‘prototype’ measure,” Robinson said. “Basically, we are able to correlate an individual emotional reaction with a prototype of that stimulus. The higher the correlation, the more prototypical or invariant the reaction appears. Negative emotional reactions tend to be more prototypical in individuals than positive emotional reactions.
Another notable aspect of the results is gender differences. The study showed that women had faster onset times, higher peak intensities, and steeper slopes in their emotional responses to aversive images than men, on average. This is consistent with the higher prevalence of anxiety and fear-related disorders among women.
“We show that women tend to have greater negative affect than men, suggesting that the paradigm can be used to understand the types of individual differences that have been highlighted in the anxiety literature,” explained Robinson.
The results of this study have important implications for the understanding and treatment of anxiety disorders. By identifying individuals with heightened threat sensitivity, clinicians could better predict who is at risk for anxiety-related problems.
For example, the DART “could be used to assess variations in ‘acute threat’ mechanisms that may predispose people to anxiety symptoms and disorders,” Robinson explained.
Research provides strong evidence that negative effects on emotional reactivity exist. But as with any study, there are limitations. The sample consisted primarily of young adults from academia, which may not be representative of the general population. Future research could include a more diverse age range and explore how these findings apply to older adults.
Additionally, the study focused on gender differences without delving into underlying causes, which could include hormonal, genetic, and sociocultural factors. Additional research is needed to analyze these influences and understand how they contribute to observed differences in threat sensitivity.
“We would like to increase the clinical relevance of this research,” Robinson said. “This would be done by focusing on clinical symptomatology, longitudinal predictions and treatment responses. »
“We live our lives in dynamic terms and it’s good to have a model of the dynamic nature of emotional reactions,” he added.
The study, “Threat Sensitivity in Emotion Dynamics: Negativity Effects and Gender Differences,” was authored by Michael D. Robinson, Roberta L. Irvin, and Muhammad R. Asad.