IF YOU had to point to the place where consciousness emerges, you would probably aim your finger squarely at your head. That is the easy bit. Exactly where the brain circuitry for consciousness lies, or how the physical properties therein seemingly transform into the subjective feeling of being, are questions that have bamboozled us for centuries. And it turns out that we might have been looking in the wrong place all along.
The brain on its own isn’t enough to generate subjective experience, says Catherine Tallon-Baudry, a neuroscientist at the Ecole Normale Supérieure in Paris, France. Without the body, the self simply wouldn’t exist. “Just as the notion of ‘car’ exists only if a certain number of components are present and interacting with each other,” she says.
Instead, researchers have come to recognise that our sense of interoception, which monitors internal body signals – such as heart rate, pain, thirst and pleasure – plays a major role in creating our thoughts and emotions. Now, many consider interoception to be a fundamental feature of consciousness, too.
Our internal organs, particularly the heart and gut, are key players in building our conscious experience, says Tallon-Baudry. Both have their own self-generated rhythm, separate from the brain – and this, Tallon-Baudry believes, provides a handy hook on which the brain can hang its sense of self.
Taking the idea a step further, Antonio Damasio at the University of Southern California says that internal body signals aren’t just involved in consciousness – they are consciousness. “People continue talking about consciousness as the great mystery that will be revealed by understanding the brain, and that’s wrong,” …