You’ve likely been taught throughout your life that humans possess only five senses.
However, researchers at Scripps Research have proposed the existence of an additional sense that continuously operates within us, potentially being the most crucial of them all.
We are all familiar with the conventional five senses: sight, smell, taste, hearing, and touch.
Yet, none of these senses account for the internal state of our bodies. This is where the sixth hidden sense is significant, and its essential role will become apparent swiftly.
This sense allows your brain to unobtrusively monitor internal body functions, such as heartbeat, blood pressure, hunger, thirst, and stress levels.
It’s why your body knows when to breathe more deeply, recognize dehydration, or activate the immune system.
This sense is known as interoception.
Professor Xin Jin, leading a part of a $14.2 million National Institutes of Health study on this subject, recently explained: “Interoception is fundamental to nearly every aspect of health, but it remains a largely unexplored frontier of neuroscience.”
Ardem Patapoutian, PhD, a neuroscience professor at Scripps Research and a recipient of the 2021 Nobel Prize in Physiology or Medicine, noted that scientists are just beginning to understand this enigmatic process.
“It’s really remarkable how little we know about these internal sensory systems compared to what we know about our external senses,” he commented.
“We’re just now beginning to identify how these neurons gather information from our organs, to decipher the neural circuits that process that information before it goes to the brain, and to figure out what the brain does with that information.”
Patapoutian’s exploration into this field began with a seemingly simple question: what occurs in a neuron when it is stimulated?
More than a decade ago, his laboratory sought to identify the molecules enabling nerve cells to detect touch.
By using a glass probe to prod individual cells, they observed neurons emitting electrical signals, akin to the body’s communication system.
Through the methodical elimination of different proteins, known as ion channels, one by one, they identified two crucial for touch sensation.
These were named PIEZO1 and PIEZO2. These small channels were pivotal in comprehending how bodies perceive sensations like pressure, movement, and balance.
Interestingly, they are found not only in skin but also in the heart, lungs, stomach lining, blood vessels, and even in the roots of plants.
These discoveries now underpin the Scripps team’s comprehensive study of interoception.
This ‘hidden sense’ may elucidate everything from the regulation of our heartbeat to the physical nature of our emotions.
So, the next time your intuition signals that something isn’t right, it might not be mere instinct; it could very well be your sixth sense functioning as it should.