Curiosity

Academics struggle to even agree on what “curiosity” actually is, often getting bogged down in whether it’s different from just plain old “information-seeking”. They can’t nail down a single definition, which honestly, feels a bit dense when you look around at how much time and effort we pour into consuming media, browsing the internet, or just finding out stuff that has no immediate payoff. But instead of getting lost in semantic debates, it’s more useful to think of curiosity as a basic drive state for information, much like hunger or thirst. It’s a fundamental part of what makes us, and many other organisms, tick.

This isn’t just a human thing. Even simple worms like C. elegans actively forage not just for food, but for information about where food might be. Their strategy isn’t just following scent; it’s designed to maximize a combination of expected reward and information about that reward. That’s a sophisticated optimization problem solved by a tiny network of neurons. Crabs, bees, ants – they’re all in the information game.

The Brain’s Valuation Machine

So, what’s the machinery behind this drive? The brain treats information value remarkably similarly to other rewards. Studies show that anticipating information, like anticipating juice or money, activates parts of the brain associated with reward anticipation, specifically areas like the caudate nucleus and inferior frontal gyrus. While one study found activation in reward anticipation areas, others noted activity in regions linked to aversive states, suggesting curiosity might sometimes feel like an unpleasant gap that needs filling. But crucially, resolving that uncertainty, getting the answer, often lights up the brain’s reward circuits.

The heavy hitters in the brain’s valuation system, particularly dopamine neurons, signal both primary rewards (like juice) and informational rewards. This suggests that our neural hardware integrates these different forms of value into a single, abstract representation. It’s like the brain has a universal currency for value, and information is readily exchangeable. One study even quantified this value in monkeys: information about a reward was worth about 25% of the reward itself. And just like with money, the value of information goes up with the stakes. This drive for information can even manifest as a preference for receiving information sooner, even if it’s strategically useless. Some researchers link this to risk-seeking behavior, arguing that risky choices inherently provide information about uncertain outcomes. The orbitofrontal cortex (OFC), a key area for evaluating choices, represents the different components of value, like the stakes and the information value, suggesting it’s a hub where these different aspects are processed before influencing decisions.

Learning on Leverage

One of the clearest functions of curiosity is to motivate learning. It’s the engine that drives us to fill those “information gaps”. Think about trivia questions: we’re most curious when we have some idea of the answer but aren’t totally sure. That moderate level of uncertainty is the sweet spot that maximizes the drive to know. And getting that answer when you’re curious doesn’t just feel good; it actually enhances memory and learning. Curiosity focuses our cognitive resources on information we need, making learning more efficient.

This plays out from the earliest stages of life. Infants aren’t just passively taking in the world; they’re actively seeking information. They have biases to look at things that are informative, like high contrast areas or faces. As they learn, their attention shifts. They don’t just prefer novelty; they prefer stimuli that are moderately different from what they already know – information that’s challenging but not completely incomprehensible. It’s a U-shaped curve: too simple (boring) or too complex (overwhelming), and they tune out. They are, in effect, optimizing their rate of information absorption.

Toddlers are like little venture capitalists in the information market, constantly exploring and experimenting to understand how the world works. They’re drawn to toys and situations that are uncertain or violate their expectations. When presented with ambiguous evidence about cause and effect, they structure their play to figure it out, acting like hypothesis-testing scientists. This isn’t just random fiddling; it’s strategic information-seeking aimed at building accurate causal models of their environment.

In essence, curiosity isn’t just a pleasant feeling or a character trait; it’s a fundamental, evolutionarily conserved drive state powered by the brain’s reward system. It motivates us to acquire the most valuable commodity of all: knowledge, which pays dividends in learning, adaptation, and navigating the world. It’s the engine of human progress and a powerful, quantifiable force shaping our behavior from infancy to adulthood.

Reviewed sources

Kidd, C., & Hayden, B. Y. (2015). The psychology and neuroscience of curiosity. Neuron, 88(3), 449-460.