Electrical signals coming from your heart and other organs influence how you perceive the world, the decisions you take, your sense of who you are and consciousness itself.
24 June 2020
PARTS of Ann Arbor bring The Truman Show to mind, with their wood-frame houses and white picket fences. Home to the University of Michigan, the city oozes middle-class prosperity and security. So, while doing research there a decade ago, Sarah Garfinkel was shocked to discover that young veterans of wars in Iraq and Afghanistan felt terrified even in Ann Arbor. “It broke my heart,” she says. And it changed the course of her career.
Garfinkel was in Michigan to study the brain circuitry involved in persistent fear. But working with traumatised veterans, she realised two things. First, a safe environment didn’t help them feel less fearful. And second, their fear was physical as well as mental: their hearts were constantly racing, their pupils dilated, their palms sweaty. “It seemed to me that what their bodies were doing was meaningful, but I was just scanning their brains,” she says. So she set out to understand the body-mind connection.
Garfinkel, now at the University of Sussex, UK, discovered that our bodies have more influence over our minds than you might imagine. “Our thoughts, feelings and behaviours are shaped in part by the internal signals that arise from our body,” she says. But it goes beyond that. It is leading her and others to a surprising conclusion: that the body helps to generate our sense of self and is a key part of consciousness. This idea has practical implications in assessing people who show little sign of consciousness. It may also force us to reconsider where we draw the line between life and death, and provide a new …