Neural activity in the cerebral cortex generates electrical impulses and synchronized oscillations, yet the transition from these processes to the feeling of 'what it is like to be oneself' remains one of science's deepest mysteries. Christof Koch, one of the world's leading consciousness researchers and director of the Allen Institute for Brain Science, has repeatedly emphasized that this very gap between physiology and experience constitutes the core of the consciousness problem.
Koch is an active proponent of Integrated Information Theory (IIT), developed by neurobiologist Giulio Tononi in 2004. According to this view, consciousness can arise where a system possesses a high degree of integrated information, meaning the entire system cannot be reduced to a simple sum of its independent parts. The main idea is that consciousness is linked to information that has causal connectivity—where the parts of the system influence each other in such a way that they function as a unified whole. Experiments using magnetic brain stimulation and measuring the Φ (phi) value confirm a correlation between the complexity of information integration and people's reports of conscious perception. However, neither the experimental data nor the theory itself has explained the main point: why does information integration at the neuronal level lead to subjective experience, rather than just data processing?
An alternative approach—the global workspace theory, proposed by cognitive psychologist Bernard Baars in 1988—views the problem differently. It emphasizes that consciousness arises through the widespread broadcasting of information throughout the brain: separate, specialized brain regions process information in parallel, but only the information that 'comes into focus'—into the so-called global workspace—becomes conscious. Koch and other neurobiologists see this theory as a promising path, but here too, the unresolved question remains: why does access to information generate experience, rather than simply allowing the system to process data faster?
Both approaches face one fundamental problem—the so-called explanatory gap, described by philosopher David Chalmers and named by him the hard problem of consciousness. Even if scientists identify the complete set of neural correlates of consciousness (NCC)—all those neural processes necessary for a specific conscious sensation—the final unresolved question will remain: how and why does physical brain activity generate qualia—the unique subjective quality of sensations? No amount of electrodes and tomographs can capture 'what it is like' for the subject themselves.
Methodological limitations of current research also prevent the conclusions from being considered final. Samples are often small, results depend on subjective verbal reports from participants, and scientists always face the difficulty of controlling for background neural activity. Recent work with AI models, where researchers have discovered structures similar to the conscious workspace, only intensifies the paradox: if functional equivalence is sufficient, then consciousness can, in principle, arise in silicon or in any system that implements the same functions.
Imagine the electrical network of a vast city: millions of light bulbs flash in a complex, seemingly intelligent rhythm, information flows between them with wondrous coherence. Engineers study every wire, every switch, draw maps of the flows—and yet none of them can pinpoint the moment when the network begins not just to *work*, but begins to *feel* darkness or light. The physiology of consciousness resembles this task: we record activity, map connections, but never find the place where physics transforms into experience.
This unresolved issue compels a re-examination not only of the fundamental foundations of neuroscience but also of practical, deeply ethical questions. If we cannot firmly answer where the boundary lies between complex information processing and genuine conscious experience, how can we judge whether animals feel pain the same way humans do? Do people in a vegetative state have hidden consciousness? Will future artificial systems become conscious? The question of where exactly consciousness begins is becoming increasingly practically significant, and questions of morality, law, and our relationship with life depend on the answer.
