Research published in journals Social cognitive and affective neuroscience This provides evidence that the brain’s reward system generates a powerful urge to seek information about what might have been, even if that information causes emotional distress. The findings suggest that the human brain treats the satisfaction of curiosity as an internal reward that can outweigh the negative emotion of regret. This research helps explain why people often feel an uncontrollable desire to explore alternative realities, such as seeing the price of a house they didn’t buy or the price of a stock they didn’t invest in.
Humans have a unique ability to reflect on their decisions and imagine different outcomes. Scientists call this counterfactual thinking. This ability helps people learn from their mistakes, but it often leads to regret when they realize that the option they didn’t choose was better than the one they did choose. Researchers conducted the study to understand why people seek out information so much, even when it has no practical purpose and can make them feel worse.
“After making a choice, people often reflect not only on the consequences of their choice, but also on possible alternative outcomes (i.e., counterfactual reality), even though it induces negative emotions (e.g., regret). The main motivation for our study was to “We investigate the mechanism behind the human desire to find alternative solutions, or ‘counterfactual curiosity,'” said study author Michiko Sakaki, a tenure-track professor at the Hector Institute for Educational Sciences and Psychology at the University of Tübingen.
Curiosity is often seen as a positive force that promotes learning and growth. However, it can also manifest as a strong motivational urge that people find difficult to resist. This drive is sometimes called incentive salience. This is a term that describes the feeling of “wanting” or “craving” that draws a person towards a reward. The scientists wanted to investigate whether the brain regions that deal with physical rewards, such as food or money, are the same brain regions that generate the urge to satisfy counterfactual curiosity.
To investigate this, researchers recruited 41 participants from the University of Reading. After removing data from those who moved too much during the scan or provided incomplete ratings, the final group consisted of 38 participants. The group included 12 men and 26 women, with an average age of approximately 21 years. Most of these participants were college students of varying academic ability levels.
Participants performed specific tasks within a functional magnetic resonance imaging scanner, often called an fMRI. fMRI is a device that measures changes in blood flow in the brain. This allows scientists to see whether specific brain areas are activated during different activities. This method is a standard tool for mapping how the human mind processes emotions and decisions.
The task used in the study was a modified version of the balloon analog risk task. In this game, participants must look at a virtual balloon and decide how many times to pump it. Each pump increases the number of points a participant can earn in that round. However, every balloon has a hidden “pop point” that is randomly determined for each trial. If the participant selects a number of pumps that exceeds this limit, the balloon will burst and the points earned will be 0.
If the balloon remains intact, the participant is able to successfully bank the points, so the trial is called a “bank” trial. After each round, participants rated their current emotional state on a scale ranging from sad faces to happy faces. This initial assessment provided a baseline of how they felt about the direct consequences of their choices.
Following this, participants entered a choice phase. They were asked if they wanted to know the actual limits of the balloon for that particular round. Checking this limit will tell you exactly how many more pumps you can create to earn more points. To obtain this information, participants had to agree to a “cost.” This resulted in a maximum wait time of 6 seconds at the end of the trial.
The researchers stress that this information was actually of no use. Because the pop point of each balloon is completely random on a trial-by-trial basis, knowing the limits of the previous balloon does not help participants predict the next balloon. After participants either saw the limit or chose not to see the limit, they provided a second emotion rating. This helped researchers measure how emotions changed after receiving counterfactual information.
According to the behavioral results, participants chose to see the balloon’s limits in 52 percent of the banking experiments. Users are more likely to ask for this information if each pump has a high point value and a low standby cost. As the researchers predicted, viewing the information often elicited negative emotions. When participants realized they could have earned more points, they felt less happy and experienced emotions consistent with regret.
This study provides evidence that this “useless” information also influenced future behavior. If participants realized they missed out on a big chance, they tended to inflate the balloon more often in the next round. This suggests that the brain uses counterfactual information to adjust behavior even when that information is not logically related to future success. The emotional impact of regret appears to drive individuals to take more risks in an attempt to avoid missing out again.
“Behaviorally, we found a strong effect of counterfactual curiosity, which is consistent with previous research,” Sakaki told Cypost. “For example, participants sought more counterfactual information when they expected the counterfactual reality to be better than reality. Participants also had significantly more negative emotions after seeking counterfactual information than when they had not sought the information.”
Brain imaging results focused on a group of structures called the striatum. The striatum is located deep in the brain and is known to be essential for motivation and reward processing. The researchers specifically looked at two parts of the striatum: the caudate nucleus and the nucleus accumbens. They also looked at the substantia nigra and ventral tegmental area, areas that produce dopamine. Dopamine is a chemical that helps the brain send signals for reward.
During the choice phase, the caudate nucleus and dopamine-producing regions showed higher levels of activity when participants decided to seek counterfactual information. This activity occurred even after the scientists calculated the latency and point values. The results of this study suggest that these brain regions generate signals that “seek” information. The brain appears to treat curiosity satisfaction as an internal reward, processed similarly to money or food.
When participants actually viewed the information, their brain activity changed. The caudate and nucleus accumbens showed increased activity depending on the magnitude of the missed opportunity. The larger the gap between the participant’s choice and the balloon’s actual limit, the stronger the response was evoked in these regions. This suggests that the striatum is involved in both the initial urge to know the truth and the subsequent processing of regret that the truth brings.
“External motivators, such as money and food, are known to change our behavior through reward networks in the brain,” Sakaki explained. “Our study found that the same brain regions are involved in choosing to seek information out of counterfactual curiosity.”
The researchers pointed out several limitations and directions for future research. Because this study primarily focused on young people in college, it is not yet clear whether these findings apply to older populations. Furthermore, the brain regions studied did not show completely consistent activity across all stages of the experiment. For example, the nucleus accumbens was highly active when feedback was revealed, but it did not show the same level of activity during the initial choice to seek that feedback.
Future research could investigate how these brain circuits function in people with different personality traits and psychological states. The scientists also suggest that further research is needed to understand the specific role of each subregion within the striatum. It remains to be seen whether these same brain patterns emerge in real-world situations that involve big life choices rather than small game points. The long-term goal is to “understand development and its effects across the lifespan,” Sakaki said.
The study, “The role of the striatum in counterfactual information seeking,” was authored by Johnny King L. Lau, Michiko Sakaki, Lily Fitzgibbon, Jasmine AL. Low, and Ko Murayama.

