Summary: A study identified a neural signature in mice that encodes the intrinsic value of information, independent of physical rewards.
The team demonstrated that lab mice actively seek out advance knowledge of future events, even when obtaining that information reduces their physical reward. Using simultaneous population neural recording, researchers discovered that approximately 20% of decision-making neurons in the orbitofrontal cortex (OFC) uniquely fire to signal the calculated value of expected information.
These findings provide a biological framework for curiosity, demonstrating that the mammalian brain processes information seeking through distinct neural representations analogous to physical rewards like food or water.
Key Facts
- Information as a Tradeable Commodity: Mice demonstrated a robust preference for advance information about water rewards, choosing informative cues even when doing so reduced the total volume of water received, proving that information carries intrinsic metabolic and computational value.
- Neural Population in the OFC: High-density neural recordings revealed that roughly 20% of individual neurons within the orbitofrontal cortex adjust their firing rates specifically in response to the expected presence and value of information.
- Dissociation of Reward Values: By varying water volumes alongside information cues, researchers successfully isolated two distinct neural activity patterns within the decision-critical OFC: one representing extrinsic value (water volume) and another representing intrinsic value (information availability).
- Uncertainty-Driven Curiosity: The likelihood of a mouse seeking informative cues increased directly with the duration of the delay before reward delivery, supporting the hypothesis that curiosity-driven information seeking acts to reduce internal states of uncertainty.
- Evolutionary Foundations: The discovery of dedicated information-valuation neurons in rodents indicates that curiosity is an ancient, hardwired mammalian mechanism rather than a cognitive capacity exclusive to primates or humans.
Source: Zuckerman Institute
We all hunger for information. Sometimes this drive leads us to a tangible reward, such as looking up reviews to find the perfect restaurant. But often we seek knowledge as an end unto itself, as when Galileo pointed his telescope at the night sky or Alice followed the rabbit down its hole. How do our brains lead us on such curiosity-driven quests for information?
Neuroscientists at Columbia University’s Zuckerman Institute have identified neurons that seem to play a role. In new research published July 30 in Nature Neuroscience, Jennifer Bussell, PhD, and colleagues uncovered a unique brain signal of the value of information.
To do so, they first demonstrated that lab mice share our desire for knowledge in and of itself. The researchers’ observations should pique the interest not just of brain scientists but of educators, philosophers, economists and anyone who is curious about where curiosity comes from.
“One of the great joys of life is getting to be curious about everything around us, and we don’t really know yet how that works in the brain,” said Dr. Bussell, an associate research scientist in the Axel lab at Columbia’s Zuckerman Institute. “This is a fascinating question that touches on everything from how children learn to how we all seek knowledge in a world full of information—and misinformation.”
People have thought about curiosity since at least the ancient philosopher Aristotle, who wrote that we all “by nature desire to know” and that we take a delight in our senses unrelated to their usefulness. Modern economists and psychologists have explored the topic by creating games in which volunteers can pay for information of no use to winning. In the middle of the 20th century, scientists designed similar games for rats and pigeons, establishing that other animals also seek out information.
Paper co-author Ethan Bromberg-Martin, PhD, of Johns Hopkins University School of Medicine, recently revived and expanded this approach in other animal models; he found that some parts of the brain respond to information in the same way as food and other external rewards–even though, unlike food, information cannot be sensed physiologically by the body. That inspired Dr. Bussell to investigate how information is identified and its value computed using the powerful neuroscience tools only available in mice.
The new research she spearheaded pivoted on offering mice the choice between two holes. One told the mice whether they were going to get a drink of water, by providing a puff of an otherwise meaningless scent, such as that of cut grass. Another hole told the mice nothing, but their chance of receiving the water was the same. The vast majority of mice chose the hole that forecast the future. They did so even when Dr. Bussell changed the rules such that picking the information hole lowered the amount of water reward they would receive.
“Since you can’t ask a mouse why it makes certain decisions, we had to design experiments in which they showed us their preferences,” said Dr. Bussell. “What we saw was that these animals had such a strong desire for knowledge about upcoming events that they would pay to receive it.”
As the mice learned to play this game, Dr. Bussell monitored large groups of neurons simultaneously in their brains. Here she drew on the deep expertise of colleagues in the Axel lab in deciphering how mouse neurons encode smell.
The team’s recent work revealed how a mental representation of a smell changes when that smell becomes associated with a water reward. With this research in hand, Dr. Bussell went looking for the neural signature of an odor becoming associated with knowledge.
By comparing brain activity when the mice sought information versus no information, Dr. Bussell identified cells behaving differently based on the animals’ expectation: some 20 percent of the neurons in a brain region called the orbitofrontal cortex, which helps animals make decisions, showed different activity in the information condition. This neural response signalled the value of the information the mice expected to receive.
Diving deeper, Dr. Bussell also compared the brain activity when the mice expected either a large or small amount of water. This helped her tease apart one pattern related to the extrinsic value of how much water a mouse expected to receive and another pattern related to the intrinsic value of the information. This representation of information value in the decision-critical orbitofrontal cortex could potentially guide animals in the pursuit of knowledge.
Why the brain of a mouse or a human would have this penchant for information remains an open question. Perhaps during the course of evolution, the importance of information that helped animals survive caused the value of knowledge itself to become hardwired. We may simply get pleasure from finding things out, a possibility that holds particular appeal to a curiosity-driven scientist like Dr. Bussell.
Another possibility is that animals simply do not like uncertainty; Dr. Bussell’s research found some evidence for this in that the longer a mouse had to wait to drink, suspended in a period of uncertainty, the more likely it was to choose information. Yet another alternative hypothesis is the view that knowing what’s coming increases the delight in anticipation, like that of looking forward to an upcoming vacation.
“The field of curiosity is just getting started,” said Dr. Bussell. She is planning future studies to further trace the neural circuitry of information and uncover additional parts of the brain that trigger curiosity.
Key Questions Answered:
A: The team designed a choice task where selecting the “information hole” delivered an olfactory cue forecasting whether water was coming. Crucially, when researchers adjusted the rules so that choosing the information hole yielded less water overall, the mice still chose it, demonstrating a willingness to trade physical reward for advance knowledge.
A: The orbitofrontal cortex (OFC) calculates and compares the values of different choices. Researchers found that about 20% of recorded OFC neurons specifically signal the intrinsic value of expected information, maintaining a population representation separate from the neurons calculating physical reward size.
A: Seeking information provides an evolutionary advantage by resolving environmental uncertainty, allowing organisms to better anticipate hazards or optimize foraging. Over evolutionary time, this adaptive drive likely transformed information itself into an intrinsically rewarding stimulus, prompting curiosity even in the absence of an immediate physical benefit.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this neuroscience research news
Author: Charles Choi
Source: Zuckerman Institute
Contact: Charles Choi – Zuckerman Institute
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Representations of the intrinsic value of information in mouse orbitofrontal cortex” by Jennifer J. Bussell, Ryan P. Badman, David Márton, Ethan S. Bromberg-Martin, L. F. Abbott, Kanaka Rajan & Richard Axel. Nature Neuroscience
DOI:10.1038/s41593-026-02377-y
Abstract
Representations of the intrinsic value of information in mouse orbitofrontal cortex
Animals are motivated to seek information that does not influence reward outcomes, suggesting that information has intrinsic value. Here we have developed an odor-based information seeking task that reveals that mice choose to receive information even though it does not alter the reward outcome.
Moreover, mice are willing to pay for information by sacrificing water reward, suggesting that information is of intrinsic value to a mouse.
We used a microendoscope to reveal neural activity in the orbitofrontal cortex (OFC) while mice learned the information seeking task. We observed the emergence of distinct representations of odors predictive of information and odors predictive of water reward.
A latent variable model recapitulated these different representations in the low-dimensional dynamics of OFC neuronal population activity. These data suggest that mice have evolved separate pathways to represent the intrinsic value of information and the extrinsic value of water reward.
Thus, the desire to acquire knowledge is observed in mice and the value of this information is represented in the OFC. The mouse now provides a facile experimental system to study the representation of the value of information, a higher cognitive variable.
