Scientists Measure Qualia for First Time – It was thought to be impossible

Scientists have found a way to make “qualia”—the private, subjective feel of experience—measurable in practice by linking specific experiences (like seeing red) to consistent brain activity patterns across different people. The central result comes from an fMRI study with 35 participants: when participants viewed different colors, their brain signals showed similarities that track the perception of the same color. That matters because qualia were long treated as fundamentally inaccessible to science, framed by philosophers as something that can’t be captured by physical descriptions alone.

For decades, the idea that qualia resist measurement drew strength from arguments associated with Thomas Nagel and David Chalmers. Nagel’s “What is it like to be a bat?” emphasized that even complete knowledge of a creature’s brain wouldn’t reveal what the experience feels like from the inside. Chalmers later sharpened the challenge into the “hard problem of consciousness,” claiming that understanding the brain’s physical processes still doesn’t explain why experience has a particular “what-it’s-like” character. Together, these views helped cast qualia as nearly mystical—outside the reach of experimental methods.

The new study pushes back on that boundary by treating subjective experience as something that can be approximated through neural “signatures.” The researchers did not claim that one person’s red is identical to another person’s red in a fully personal, first-person sense. Instead, they reported that the brain patterns associated with seeing the same color are structurally and approximately similar across participants—an objective bridge between private experience and measurable data. In effect, it suggests that “your red” and “my red” can be compared at the level of neural correlates.

This finding fits a broader shift away from purely philosophical framing toward computational and mathematical approaches to consciousness. One influential direction comes from neuroscientist Anil Seth and co-authors, who propose that the brain generates predictions about incoming sensory input and then updates its internal model when reality differs. In that framework, qualia correspond to key elements of the brain’s predictive machinery—especially for experiences that are tightly linked to sensory structure, such as color or body orientation.

Another effort, embodied by the Qualia Research Institute, aims to build a mathematical framework for subjective experience by mapping the “state space of consciousness,” essentially charting the landscape of possible experiences. Even philosophers are increasingly engaging with the idea that colors and other experiential qualities may be more objective than once assumed. A recent book, The Metaphysics of Color, argues that colors are real in a way comparable to physical quantities like temperature.

Taken together, the message is clear: qualia may not be beyond science after all. If researchers can reliably map experience to neural patterns—and eventually to formal models—then the long-term implications extend beyond theory, raising the possibility of sharing or recreating aspects of experience across people and even other minds. The immediate achievement is narrower but pivotal: objective measurement and comparison of qualia-like experiences using brain data.