Consciousness is one of science’s final frontiers

Add to myFT Laboratories around the world will scan the brains of 500 volunteers to test competing theories on the origins of consciousness © (c) Stockdevil | Dreamstime.com Share on Twitter (opens new window) Share on Facebook (opens new window) Share on LinkedIn (opens new window) Save Anjana Ahuja 19 HOURS AGOPrint this page18 Nobody perceives or experiences the world like you do.

You are an ever-changing, unique collection of perceptions, memories and expectations, of which you are constantly aware. The sense that you know your own mind is your consciousness at work. Yet despite thousands of years of inquiry by philosophers and scientists, the origins of consciousness have never been truly understood. How does a physical thing, the brain, generate a subjective experience, such as delight in the beauty of autumn?

We have some clues: disease, stroke or injury can damage it; we fleetingly surrender it during sleep or while anaesthetised. But the exact neurological or physiological structures that conspire to produce consciousness remain elusive. Now, a $20m effort will pit competing theories against each other. The project, by the Templeton World Charity Foundation, was announced last week at the Society for Neuroscience meeting in Illinois and reported in the journal Science.

Appropriately for a head-to-head contest, the first round will pit the front of the brain against the back. The Global Neuronal Workspace theory, led by Professor Stanislas Dehaene at the Collège de France, suggests a starring role for the prefrontal cortex, often called the brain’s “CEO” because of its importance in planning and problem solving. The theory contends that competing sensory stimuli jostle for neural attention, but only those that are prioritised cut through to trigger other brain processes, such as working memory and decision-making.

It is this “global broadcasting” across the brain that we experience as conscious thought. Or does the engine of consciousness purr at the back of the brain? The Integrated Information Theory, pioneered by Professor Giulio Tononi from the University of Wisconsin, argues that the more interconnected a system’s parts are, the more likely it is to be conscious. He predicts that intricately connected cells near the back of the brain should make a major contribution. A logical consequence of Prof Tononi’s mathematical idea, in which interconnectedness and information exchange are pivotal, is that non-biological matter could also be conscious.

This radical view that inanimate matter could have an inner life, known as panpsychism, is surprisingly well-regarded among philosophers. Our brains are, after all, composed of atoms, just like all the other stuff in the universe. For others, though, this renders the IIT theory self-evidently absurd. The architects of the theories will play no part in collecting or analysing data; they will simply make predictions against which their ideas will stand or fall. Laboratories around the world will scan the brains of 500 volunteers while they carry out tasks related to consciousness, such as image recognition.

Electroencephalography, or EEG, which uses electrodes to measure electrical activity in the brain, will also feature. The collective effort will be managed by Lucia Melloni at the Max Planck Institute for Empirical Aesthetics in Frankfurt. The play-offs between as many as 11 different theories will help scientists “get closer to understanding consciousness [by] increasing confidence in the theory that survives adversarial collaboration”.

First results are expected in about three years. Human consciousness is a remarkable phenomenon: the means by which we comprehend the world, but seemingly impervious to scientific inquiry. A deeper understanding may allow us, for instance, to more accurately infer levels of consciousness in locked-in patients and non-human animals. Then again, some philosophers and scientists think human consciousness itself is an illusion, a charade in the cranium destined to keep us fooled.