The Eighth Sense

Staande naakte vrouw met lang haar (1926) by Henk Schilling. Original from The Rijksmuseum. Digitally enhanced by rawpixel.




Trust your gut. Do not get your bowels in an uproar. Do you have the stomach for this?

Turns out we have spoken, all along, the truth that is now one of the hottest new topics in neuroscience: the power our internal organs have to modulate our feelings, our decisions, our lives. This is interoception, and it has been declared our eighth sense. An awareness of what is going on inside one’s body, it accounts for much of that magical sort of knowing we have long called “intuition,” an inner voice, inner wisdom. When it is clear and strong, it can fend off anxiety and depression all by itself. When it is absent, emotions go haywire.

Entire conferences are being devoted to interoception. Trends in Neuroscience did a special issue on it, and research is piling up fast. Me, I had never heard the word (and neither has Microsoft Word, which keeps underlining it in red). As for interoception being the eighth sense, I have lost count. Thinking of ESP as the sixth was fun, but number seven—proprioception, a sense of where we are in space—never even registered, probably because I rarely have it.

Eyebrows raised, I google “number of senses humans have” and find lists of eighteen, twenty, even thirty-three, which sounds like wishful thinking in the Marvel universe but has a firm defense from scientists at the University of Glasgow. Number eight puzzles me, though. Why mess with all that glistening pink viscera, when it carries on so dutifully without us even noticing?

Because the signals it sends to the brain trigger our emotions. There is a constant conversation going on inside our body, lots of excited whispering back and forth, and often the other organs get the gossip before the brain does. The brain then decides what to feel based on the news it is hearing. Our heart is racing, so we must be scared. Our stomach clutches, so we must be anxious.

“Listen to your heart,” one researcher suggests—meaning this literally, not as maudlin advice. When I try, it takes me several seconds to even register the beat that means I am alive. Ah, there it is. But can I feel it in my wrist? In my temples? Not a chance. Many of us walk around so oblivious of our inner workings, so devoid of interoception, that we are numb and lethargic. Others are so hyperaware of their bodily sensations that they overreact, spiraling into neurotic alarm. I somehow manage to alternate between those extremes, skipping the middle altogether.

In tiny moments of panic (Where did I leave my phone? Now I am both lost and late. Did I just do something truly stupid?) I practice pausing to check my body. Is it flushed, telling me I am embarrassed, or chilled, signaling dread? Are my muscles tightening with an invisible winch? Is my heart racing or my tummy churning? Am I forgetting to breathe? Like a meticulous retail clerk, I take inventory—and then, oddly, I feel calmer. Tracing an emotion back to such prosaic beginnings reminds me that it might not be a rational response, might not even be a necessary one.

Years ago, the neuroscientist Antonio Damasio studied people with damage in the part of the brain that creates unconscious bodily reactions. Show them a horrific car crash, and they have no physiological response—and therefore no emotional response. They have trouble making even the simplest decisions, like what to wear or what to have for breakfast. We need emotion to make good decisions. And we need unconscious physiological responses in order to have emotions.

Western scientists conveniently overlooked emotion for decades, dismissing it as irrational and female, a source of bias and hysteria best avoided altogether. Now they are forced to acknowledge that simply by paying attention to internal sensations, you can head off hysteria, angst, or dejection.

Regular exercise helps, too: if you are out of shape, “your heart will race more when you experience challenges—be it physical or emotional,” Hugo Critchley, a professor of psychiatry at Brighton and Sussex Medical School, tells The Guardian. If you are fit, your body adapts more easily to changing conditions, which can make you feel stronger, calmer, and more in control. Exercise can also make you more accurate in reading and interpreting your body’s signals. (As can mild electric stimulation to the vagus nerve, which connects the gut, heart, and brain.) With clearer dialogue between our innards and our brain, our emotional responses tend to be more proportional and measured, and we are less likely to catastrophize. We find an equilibrium in which we are neither hyperresponsive, which frays our nerves and damages our bodies, nor so cowboy tough that we lose the ability to respond when we should.

Without a steady internal compass, we crumble at the slightest criticism and rage at the smallest rejection. Or we go the other direction and forget how to feel, how to empathize, how to listen to that soft, maddening inner voice that knows exactly what we should do. I know this because I am quite good at overreacting, even better at oblivion. The murmurings of all that squishy stuff inside me is discomfiting; why attend to it? Mind over matter. Power on. This is no time to contemplate spasms in the bowels or a gush of acid in the tummy.

The upshot? Like many of us, I lack “body literacy”—the ability to identify and articulate internal sensory experience. Weird, that interoception would be so hard to come by. People have known how to perceive the world through their inner organs for centuries. “You must enjoy a work of art in your stomach,” William Morris insisted. Alessandro Monti, a neuroscience researcher, points out that our very sense of self, our continuing identity, connects to our gut, our breath, our heart. They are always with us, always sending information. “This coupling between brain and viscera is a permanent feature of your physiology,” he writes. “You can close your eyes, cover your ears, hold your nose or seal your mouth, but you cannot cut yourself off from your bowels.”

Our most ethereal emotions start deep in their coils.


Read more by Jeannette Cooperman here.